Biology of Blood and Marrow Transplantation - Articles in Press

A Meta-Analysis of Unrelated Donor Umbilical Cord Blood Transplantation versus Unrelated Donor Bone Marrow Transplantation in Acute Leukemia Patients - Accepted Manuscript

Haoran Zhang, Junmin Chen, Wenzhong Que — 2012-01-30

Abstract: Umbilical cord blood has emerged as an alternative stem cell source to bone marrow or peripheral blood stem cells. Unrelated donor cord blood transplantation (UCBT) is also potentially curative for acute leukemia. However, the effect of unrelated donor bone marrow transplantation (UBMT) and UCBT on the outcome of patients with acute leukemia has not been systematically reviewed. In the present meta-analysis, we systematically searched Cochrane Library, MEDLINE, EMBASE and CNKI up to May 2011. Two reviewers extracted data independently. Seven studies totaling 3389 patients have been assessed. Pooled results found that the incidence of engraftment failure and transplant-related mortality were higher in UCBT than in UBMT, relative risks (RRs) were 4.27 (95% CI 2.94-6.21) and 1.27 (95% CI 1.01-1.59), respectively. The rate of acute and chronic graft-versus-host disease in UCBT group were significantly lower than that in the UBMT group, RRs were 0.71 (95% CI 0.65-0.79) and 0.69 (95% CI 0.52-0.91), respectively. The relapse rate was similar between UCBT and UBMT group. The leukaemia-free survival and overall survival were significantly lower in UCBT group than in UBMT group, RRs were 1.14 (95% CI 1.07-1.22) and hazard ratios were 1.31 (95% CI 1.16-1.48), respectively. Subgroup analysis showed that in acute lymphoblastic leukemia patients the survival was similar between UCBT and UBMT.

Of Genes, Blocks and Haplotypes - Accepted Manuscript

Effie W. Petersdorf — 2012-01-30

Rapid Thymic Reconstitution Following Bone Marrow Transplantation in Neonatal Mice is VEGF-Dependent - Accepted Manuscript

2012-01-25

Abstract: Age-related differences in thymic function influence the rapidity of T cell reconstitution following hematopoietic stem cell transplantation (HSCT). In adults, thymic reconstitution is delayed until after marrow engraftment is established, and is significantly improved by approaches that increase marrow chimerism, such as pre-transplant irradiation. In contrast, we show that neonatal mice undergo more rapid and efficient thymic reconstitution than adults, even when bone marrow engraftment is minimal and in the absence of pre-transplant radiation. We have previously shown that the neonatal thymus produces high levels of vascular endothelial growth factor (VEGF) that drives angiogenesis locally. In this report we show that inhibition of VEGF prior to HSCT prevents rapid thymic reconstitution in neonates, but has no effect on thymic reconstitution in adults. These data suggest that the early, radiation independent, thymic reconstitution unique to the neonatal host is mediated through VEGF, and reveals a novel pathway that might be targeted to improve immune reconstitution post-HSCT.

Evaluation of minimal residual disease by real-time quantitative PCR of Wilms´ tumor 1 (WT1) expression in patients with acute myeloid leukemia after allogeneic stem cell transplantation. Correlation with flow cytometry and chimerism - Accepted Manuscript

2012-01-25

Abstract: Background: Relapse remains the main cause of treatment failure in acute myeloid leukemia (AML) after allogeneic hemopoietic stem cell transplantation (SCT). WT1 has been reported to be overexpressed in over 90% of AML cases, and can therefore be used for MRD monitoring. The aim of this study was to evaluate the usefulness of WT1 expression in AML patients after SCT as a relapse predictor marker, and compare it with that of flow cytometry and chimerism studies.Design and methods: WT1 expression was assessed retrospectively using real time quantitative PCR in bone marrow and peripheral blood from 21 patients.Results: Patients were classified according to WT1 dynamics post-transplantation. Eleven out of the 21 patients showed low and stable WT1 levels. All these 11 patients showed complete chimerism (CC) and negative MRD by flow cytometry (FC) and remained in CR with a median follow-up of 12 months (5.3-42). On the other hand, 10/21 patients showed WT1 overexpression after SCT. Nine out of these 10 patients relapsed. The incidence of relapse in the two groups of patients according to WT1 expression post-SCT was significantly different (p=0.00003). Relapse in the 9 patients occurred in a median of 314 days (50-560). Interestingly, from these 9 relapsed patients, relapse was first predicted by WT1 (with negative FC and CC) in 7 patients.Conclusions: WT1 overexpression correlated with disease burden in AML patients before and after allogeneic SCT. In relapsed patients, both medullar and extramedullary relapse were anticipated by WT1 overexpression compared to FC and chimerism.

Risk Factors for Molecular Detection of Adenovirus in Pediatric Hematopoietic Stem Cell Transplant Recipients - Accepted Manuscript

2012-01-25

Abstract: Adenovirus (AdV) infections are a major cause of morbidity and mortality in hematopoietic stem cell transplant HSCT) patients. To evaluate the use of molecular AdV testing in HSCT at our institution and identify risk factors for AdV viremia and disease, we performed a retrospective cohort study of all HSCT patients who had undergone AdV polymerase chain reaction (PCR) testing, over a two year period. Two cohorts were identified: Cohort 1 consisted of patients testing positive for AdV (n=7); Cohort 2 consisted of patients testing negative (n=36). Overall patient characteristics were not statistically different between cohorts. The following medication exposures were identified as risk factors influencing AdV status by comparing Cohort 1 with Cohort 2: preparatory regimens utilizing fludarabine (RR 8.73, CI 1.18-64.27, p 0.006), melphalan (RR 3.47, CI 0.76-15.94, p 0.08), and/or cyclophosphamide (RR 0.18, CI 0.02-1.4, p 0.05), and GVHD prophylaxis with methylprednisone (RR 3.73, CI 1.01-13.9, p 0.04). AdV+ pts had higher GVHD grades with higher rates of GVHD of the gastrointestinal tract (RR 4, CI 1.18-13.5, p 0.03) compared to AdV- pts. Amongst pts with AdV+ testing, 4/7 had concomitant clinical manifestations of disease including: pneumonia, diarrhea, and/or disseminated disease. Clinical outcomes in symptomatic pts included resolution of disease in 2/4 pts, and death in 2/4 pts. All AdV+ pts received antiviral therapy, including one pt with severe disseminated disease that resolved following administration of liposomal cidofovir. Our study at a large pediatric HSCT center provides important preliminary data for development of a prospective trial destined to identify specific HCST patient subpopulations that might benefit most from molecular screening and early pre-emptive therapy.

Systematic review of randomized controlled trials of hematopoietic stem cell mobilization strategies for autologous transplantation for hematologic malignancies - Accepted Manuscript

Dawn Sheppard, Christopher Bredeson, David Allan, Jason Tay — 2012-01-18

Abstract: Background: Collection of adequate hematopoietic stem cells (HSCs) is necessary for successful autologous transplantation, however a proportion of patients fail to collect the minimum number of cells required. We summarized the efficacy and safety of HSC mobilization strategies.Methods: We performed a systematic review of randomized controlled trials (RCTs) comparing HSC mobilization strategies prior to autologous transplantation for hematologic malignancies. The primary outcome was CD34+ cell yield. Secondary outcomes included number of aphereses, proportion of failures, rate of count recovery and adverse events.Results: We identified 28 articles within 3 broad strategies. Using a cyclophosphamide with growth factor strategy (10 articles), CD34+ cell yield is improved by addition of molgramostim to cyclophosphamide (1.4 vs. 0.5 x 106/kg, p = 0.0165), addition of cyclophosphamide to filgrastim (7.2 vs. 2.5 x 106/kg, p = 0.004), and addition of ancestim to cyclophosphamide and filgrastim (12.4 vs. 8.3 x 106/kg, p = 0.007).Within a growth factor based strategy (6 articles), addition of plerixafor improves CD34+ cell yield over filgrastim alone in multiple myeloma (MM) (11.0 vs. 6.2 x 106/kg, p < 0.001) and non-Hodgkin lymphoma (NHL) (5.69 vs. 1.98 x 106/kg, p < 0.01). With combination or non-cyclophosphamide based chemotherapy (12 articles), higher dose filgrastim (8.2 vs. 4.7 x 106/kg for 16 vs. 8 mcg/kg daily of filgrastim, respectively, p < 0.0001) and addition of rituximab to etoposide and filgrastim (9.9 vs. 5.6 x 106/kg, p = 0.021) improve CD34+ cell yield.Conclusions: Growth factor alone, following chemotherapy, ancestim or plerixafor provide adequate autologous HSC grafts for the majority of patients. While some strategies result in higher CD34+ cell yield, this potentially comes at the expense of increased toxicity. As all strategies are reasonable, programmatic and patient specific considerations must inform the approach to autologous graft mobilization.

The graft-versus-tumor effect according to the type of graft-versus-host disease defined by NIH consensus criteria and the associated outcomes - Accepted Manuscript

2012-01-18

Abstract: The impact of graft-versus-host disease (GVHD) by the NIH consensus criteria (NCC) on survival has rarely been investigated with a large cohort of patients with GVHD presenting before and after day 100. We retrospectively investigated 775 patients who underwent allogeneic stem cell transplantation (SCT) and assessed the GVHD effects on survival by the time-dependent covariates in Cox proportional hazards regression models. Using the NCC, all patients were reclassified into four groups: (1) No GVHD (n=251); (2) only acute GVHD (aGVHD, n=199) including 26 patients with late aGVHD; (3) classic chronic GVHD (cGVHD, n=232); (4) overlap syndrome (OS, n=93). Multivariate analyses showed that classic cGVHD (HR 0.46; 95% CI, 0.27-0.77) and OS (HR 0.52; 95% CI, 0.28-0.96) can lead to significantly decreased risk of relapse, whereas only aGVHD was not associated with relapse rates (HR 1.11; 95% CI, 0.76-1.63). All aGVHD events, including the period of aGVHD in patients who developed cGVHD after aGVHD, also did not affect the risk of relapse (HR 0.74; 95% CI, 0.49-1.12). Any groups of GVHD by NCC were significantly associated with higher non-relapse mortality in common. Finally, patients with only aGVHD had significantly lower overall survival and disease-free survival compared to no GVHD group, in contrast to favorable survival outcomes in patients with cGVHD without prior aGVHD. This study demonstrates that GVHD-type by the NCC has different graft-versus-tumor effects and further studies will be needed to investigate risk factors, pathogenesis, and biomarkers for each type of GVHD by the NCC.

National Cancer Institute, National Heart, Lung and Blood Institute/Pediatric Blood and Marrow Transplantation Consortium First International Consensus Conference on Late Effects after Pediatric Hematopoietic Cell Transplantation: The Need for Pediatric-Specific Long-Term Follow-up Guidelines - Uncorrected Proof

2012-01-16

Existing standards for screening and management of late effects occurring in children who have undergone hematopoietic cell transplantation (HCT) include recommendations from pediatric cancer networks and consensus guidelines from adult-oriented transplantation societies applicable to all HCT recipients. Although these approaches have significant merit, they are not pediatric HCT-focused, and they do not address post-HCT challenges faced by children with complex nonmalignant disorders. In this article we discuss the strengths and weaknesses of current published recommendations and conclude that pediatric-specific guidelines for post-HCT screening and management would be beneficial to the long-term health of these patients and would promote late effects research in this field. Our panel of late effects experts also provides recommendations for follow-up and therapy of selected post-HCT organ and endocrine complications in pediatric patients.

Decreased serum testosterone levels in long-term adult survivors with fatty liver after childhood stem cell transplant - Accepted Manuscript

2012-01-16

Abstract: Fatty liver and male gonadal dysfunction are potential late effects of therapy in adult survivors treated with stem cell transplantation (SCT) in childhood. Obesity and metabolic syndrome are also associated with low serum testosterone levels in the general population. However, the relationship between the degree of fatty liver and changes in serum testosterone levels in adult survivors has not been fully studied. We reviewed the clinical records of thirty-four male patients who received allogeneic SCT in childhood or adolescence. Median age at SCT was 10.0 years and median follow-up duration after SCT was 15.9 years. All patients except one showed no tendency to be overweight/obese during the follow-up period. Fatty liver was diagnosed in 15 patients by ultrasound 4–20 years after SCT. Patients who received cranial radiation therapy prior to SCT were more likely to develop fatty liver and insulin resistance. Moreover, fatty liver was statistically associated with decreased serum testosterone levels compared with non-fatty liver (median 527 ng/dL, range 168-944 ng/dL vs 302 ng/dL, 165-698 ng/dL, P < 0.0001). Changes in testosterone levels after SCT are affected not only by primary gonadal dysfunction but also by subsequent development or deterioration of fatty liver.

Intermediate- versus low-dose cyclophosphamide and granulocyte colony stimulating factor for peripheral blood stem cell mobilization in multiple myeloma patients treated with novel induction therapies - Accepted Manuscript

2012-01-16

Abstract: Peripheral blood progenitor cell (PBPC) mobilization with intermediate-dose cyclophosphamide (ID-CY) and G-CSF has been shown to be more efficacious, albeit more toxic than low-dose CY (LD-CY) containing mobilization regimens in multiple myeloma (MM) patients treated with conventional therapies. However, the relative importance of CY dose intensity in PBPC mobilization following novel induction regimens is not known. Herein we report mobilization outcomes of 123 patients who underwent transplantation within 1-year of starting induction chemotherapy with novel agents. Consecutive patients undergoing mobilization with ID-CY/G-CSF (3-4 gm/m2) (n=55) at one institution were compared against patients receiving LD-CY/G-CSF (1.5 gm/m2) (n=68) at a different transplant center. At baseline, the two groups were well balanced, except for more frequent prior lenalidomide use in the ID-CY group (p=0.04). Compared to LD-CY, ID-CY use was associated with higher median peak PB CD34+ cell count (35/ul vs. 160/ul, p<0.001), CD34+ yield on day 1 of collection (2.6 x 106/kg vs. 11.7 x 106/kg, p=<0.001), and total CD34+ cell yield (7.5 x 106/kg vs. 16.6 x 106/kg, p=<0.001). Six patients in the LD-CY group had mobilization failure, while no patient in the ID-CY group had mobilization failure. Significantly higher proportion of patients (p-value<0.001) were unable to collect ≥5 x 106/kg and ≥10 x 106/kg CD34+ cells in LD-CY group. Neutrophil and platelet engraftment was significantly faster in the ID-CY patients, likely because of higher infused CD34+ cell dose. In conclusion, compared with LD-CY, ID-CY produced a more robust PBPC mobilization and significantly reduced the rates of mobilization failure. These data caution against the use of LD-CY containing mobilization strategy in MM patients undergoing stem cell collection following novel induction regimens.

Pre-Transplant Therapy with Azacitidine Versus Induction Chemotherapy and Post-Transplant Outcome in Patients with MDS - Accepted Manuscript

2012-01-16

Abstract: While allogeneic hematopoietic cell transplantation (HCT) has proven curative potential for myelodysplastic syndrome (MDS), relapse after HCT remains a problem. Pre-transplant cytoreduction with induction chemotherapy (IC) has been utilized to reduce relapse rates, but is associated with significant toxicity and mortality. Hypomethylating agents may achieve cytoreduction with limited toxicity; however, data on the effect of pre-HCT hypomethylation on post-HCT outcomes are limited. We retrospectively reviewed results in 68 patients who underwent allogeneic HCT for MDS or acute myeloid leukemia (AML) transformed from MDS. Thirty-five patients had received cytoreduction with azacitidine prior to HCT with either a high-dose (40%) or a reduced-intensity (60%) conditioning regimen, and 33 had undergone IC prior to HCT with high-dose conditioning. The estimated one-year overall survival was 57% in the azacitidine group and 36% in the IC group. The risk of post-HCT mortality (HR 0.68, 95% CI 0.35-1.30), non-relapse mortality (HR 0.99, 95% CI 0.41-2.34), and relapse (HR 0.34, 95% CI 0.41-2.34) were lower in the azacitidine group compared to the IC group, but only the hazard for relapse was significantly lower. After adjustment for cytogenetic risk, IPSS, and donor, the rates of post-HCT relapse for the two cohorts were similar. While the current study was retrospective and non-randomized and needs to be interpreted in this context, the results add to the growing evidence that pre-HCT therapy with azacitidine is associated with less toxicity than IC, and may allow for similar post-HCT outcomes.

Polymorphisms in the immunoregulatory genes are associated with hematopoietic recovery and increased susceptibility to bacterial infections in patients with thalassaemia major undergoing matched related hematopoietic stem cell transplantation (HSCT) - Accepted Manuscript

2012-01-16

Abstract: In this study the impact of polymorphisms in the genes of pro-inflammatory (IL-β, TNF-α, IL-6, IFN-γ), anti-inflammatory (TGF-β, IL-10, IL-Ra) and other immunoregulatory factors (FcγRIIa, NOS3) along with the conventional risk factors on the rate of hematopoietic recovery and first episodes of bacterial, viral, or invasive fungal infections in 102 patients with beta thalassaemia major who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) with relatively uniform protocols at our centre from June 1995 to June 2004 with a minimum follow-up of atleast two years were studied retrospectively for 180 days after HSCT. Our data show that 1) Donor IL-1RN*2/2 (HR=2.4, 95%CI 1.17-5.09, P=0.018) and FCγRIIA +4481G/G genotypes (HR=3.1, 95% CI 1.56-6.31, P=0.001) increased the incidence of bacterial infection; 2) Fungal infection was increased in recipients with whose donors had IFN-γ +874 T/T genotype (HR=3.8; 95%CI 1.08-13.62; P=0.037); 3) Time to neutrophil recovery was shorter in splenectomized patients (HR=3.1; 95% CI 1.70-5.64; P<0.001), donors without IL-10 -1082A, -819T, -592A haplotype (HR=1.6; 95% CI 1.02-2.39; P=0.039) and recipients with IFN-γ +874 A/A genotype (HR=1.6; 95% CI 1.05-2.56; P=0.029); and 4) Time to platelet recovery was shorter in patients with IL-10 -1082 A/A genotype (HR=1.8; 95% CI 1.14-2.68; P=0.010) and with donors having TNF-α -308 G/G genotypes (HR=1.8; 95% CI 1.06-2.93; P=0.028). These data suggest that outcome after allo SCT could be affected by many factors. The mechanisms by which they bring about such impact needs further evaluation.

The Use of Back-up Units to Enhance the Safety of Unrelated Donor Cord Blood Transplantation - Uncorrected Proof

2012-01-13

The inability to obtain additional stem cells is a disadvantage of unrelated donor cord blood transplantation (CBT). Moreover, in the event of problems with unit shipment, compromised unit quality, thaw mishaps, or graft failure, the time to secure a back-up graft could be unacceptable. Emergent shipment of 1 to 2 back-up units that have been previously typed and reserved could overcome this limitation. However, the advantages of this approach are not established. Therefore, we present our use of back-up units over a 5.5-year period. Six of 121 CBT recipients (5%) required back-up unit infusion. Indications included shipment mishaps (n = 2), poor unit viability (n = 2), significant infusion reaction (n = 1), and graft failure (n = 1). Lack of back-up units would have caused transplantation delay or infusion of inferior quality units. Five of the 6 patients achieved sustained donor engraftment. We demonstrate that back-up units are emergently required in a significant minority of patients supporting the incorporation of at least 1 back-up unit in cord blood (CB) selection algorithms to enhance CBT safety.

To Induce, or Not to Induce, that is the (Still Unanswered) Question - Uncorrected Proof

Robert J. Soiffer — 2012-01-13

A 41 year old man presents to you with pancytopenia. He is asymptomatic except for mild fatigue. Liver, pulmonary, and kidney functions are normal. Bone marrow biopsy is normocellular with multilineage dysplasia. Myeloblasts represent 15% of the marrow cellularity. There are no circulating peripheral blasts. Chromosome analysis reveals monosomy 7 in 13 of 20 metaphases. The patient’s brother is healthy and HLA-identical. Based on the patient’s diagnosis of myelodysplastic syndrome, high international prostate symptom score, lack of comorbidities, and available HLA-identical sibling donor, you recommend allogeneic hematopoietic cell transplantation (HCT) .

Prophylactic and Preemptive Therapy with Dasatinib after Hematopoietic Stem Cell Transplantation for Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia - Uncorrected Proof

2012-01-11

To the Editor: Patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) respond poorly to conventional chemotherapy, with reported long-term overall survival (OS) rates of ∼10%. Recent induction therapy based on tyrosine kinase inhibitors (TKIs), alone or in combination, has achieved complete response rates as high as 75%-95%; however, these promising results are transitory, and effective long-term maintenance strategies are lacking . Although one retrospective study has suggested that upfront therapy with imatinib might make it possible to avoid consolidation therapy with allogeneic hematopoietic stem cell transplantation (HSCT), the presence of the Ph chromosome remains a primary indication for HSCT. Indeed, patients treated with HSCT have a 30%-60% increase in long-term survival rates and a lower risk of relapse . The presence of minimal residual disease (MRD) after allogeneic or autologous HSCT for Ph+ALL is highly predictive of hematologic relapse.

Cotransplantation of Ex Vivo Expanded and Unexpanded Cord Blood Units in Immunodeficient Mice Using Insulin Growth Factor Binding Protein-2–Augmented Mesenchymal Cell Cocultures - Uncorrected Proof

2012-01-11

Ex vivo expansion of cord blood (CB) hematopoietic stem cells and cotransplantation of 2 CB units (CBUs) could enhance the applicability of CB transplantation in adult patients. We report an immunodeficient mouse model for cotransplantation of ex vivo expanded and unexpanded human CB, showing enhanced CB engraftment, and provide proof of concept for this transplantation strategy as a means of overcoming the limiting cell numbers in each CBU. CBUs were expanded in serum-free medium supplemented with stem cell factor, Flt-3 ligand, thrombopoietin, and insulin growth factor binding protein-2 together with mesenchymal stromal cell coculture. Unexpanded and expanded CB cells were cotransplanted by tail vein injection into 45 sublethally irradiated nonobese diabetic SCID-IL2γ−/− (NSG) mice. Submandibular bleeding was performed monthly, and mice were sacrificed 4 months after transplantation to analyze for human hematopoietic engraftment. Expansion of non-CD34+ selected CB cells yielded 40-fold expansion of CD34+ cells and 3.1-fold expansion of hematopoietic stem cells based on limiting dilution analysis of NSG engraftment. Mice receiving expanded grafts exhibited 4.30% human cell repopulation, compared with 0.92% in mice receiving only unexpanded grafts at equivalent starting cell doses, even though the unexpanded graft predominated in long-term hematopoiesis (P = .07). Ex vivo expanded grafts with lower initiating cell doses also demonstrated equivalent engraftment to unexpanded grafts with higher cell dose (8.0% versus 7.9%; P = .93). In conclusion, ex vivo expansion resulted in enhanced CB engraftment despite eventual rejection by the unexpanded CBU.

Peripheral Blood CD34+ Cell Enumeration as a Predictor of Apheresis Yield: An Analysis of More Than 1000 Collections - Uncorrected Proof

2012-01-05

The role of the peripheral blood (PB) CD34+ cell count in predicting the CD34+ cell yield in hematopoietic progenitor cell apheresis (HPC-A) collections is well established. However, sometimes unexpectedly poor CD34+ cell yields are obtained. To determine the effect, if any, of a range of factors on the ability of the PB CD34+ count to predict collection CD34+ cell count, we performed a retrospective analysis on consecutive HPC-A collections between 2004 and 2008. Factors investigated included mobilization regimen, PB white blood cell count, body weight, and disease. After exclusion of collections involving apheresis complications, a total of 1225 PB CD34+ cell results with corresponding collection CD34+ cell results from 458 patients were analyzed. Although differences in the median PB CD34+ cell counts and collection CD34+ cell counts were seen between mobilized collections with chemotherapy plus granulocyte colony-stimulating factor and those with granulocyte colony-stimulating factor alone, the predictive capability of the PB CD34+ cell count for the collection CD34+ cell yield remained similar. Although poorer collection efficiencies were observed in the myelodysplastic syndrome/myeloproliferative disorder diagnostic subgroup, our findings confirm that PB CD34+ cell analysis remains a powerful and irreplaceable tool for predicting HPC-A CD34+ cell yield.

IL-2–Targeted Therapy Ameliorates the Severity of Graft-versus-Host Disease: Ex Vivo Selective Depletion of Host-Reactive T Cells and In Vivo Therapy - Uncorrected Proof

Shai Yarkoni, Tatyana B. Prigozhina, Shimon Slavin, Nadir Askenasy — 2012-01-05

T cell depletion prevents graft-versus-host disease (GVHD) but also removes T cell-mediated support of hematopoietic cell engraftment. A chimeric molecule composed of IL-2 and caspase-3 (IL2-cas) has been evaluated as a therapeutic modality for GVHD and selective ex vivo depletion of host-reactive T cells. IL2-cas does not affect hematopoietic cell engraftment and significantly reduces the clinical and histological severity of GVHD. Early administration of IL2-cas reduced the lethal outcome of haploidentical transplants, and survivor mice displayed markedly elevated levels of X-linked forkhead/winged helix (FoxP3+; 50%) and CD25+FoxP3+ T cells (35%) in the lymph nodes. The chimeric molecule induces in vitro apoptosis in both CD4+CD25− and CD4+CD25+ subsets of lymphocytes from alloimmunized mice, and stimulates proliferation of cells with highest levels of CD25 expression. Adoptive transfer of IL2-cas–pretreated viable splenocytes into sublethally irradiated haploidentical recipients resulted in 60% survival after a lethal challenge with lipopolysaccharide, associated with elevated fractions of CD25highFoxP3+ T cells in the lymph nodes of survivors. These data demonstrate that ex vivo purging of host-presensitized lymphocytes is effectively achieved with IL2-cas, and that IL-2–targeted apoptotic therapy reduces GVHD severity in vivo. Both approaches promote survival in lethal models of haploidentical GVHD. The mechanism of protection includes direct killing of GVHD effectors, prevention of transition to effector/memory T cells, and induction of regulatory T cell proliferation, which becomes the dominant subset under conditions of homeostatic expansion.

In Vitro Evaluation of Graft-versus-Graft Alloreactivity as a Tool to Identify the Predominant Cord Blood Unit before Double Cord Blood Transplantation - Uncorrected Proof

2012-01-05

The transplantation of 2 cord blood (CB) units obtained from unrelated donors (double CBT) is an effective strategy for adult patients with hematologic malignancies. Sustained hematopoiesis after double CBT is usually derived from a single donor, and only a few transplant recipients displaying a stable mixed donor–donor chimerism have been reported. We investigated the mechanisms underlying single-donor predominance in double CBT by studying in vitro the role of the graft-versus-graft cell-mediated immune effect in 2-way mixed lymphocyte culture (MLC), along with the contribution of differential hematopoietic progenitor (HP) potency in HP mixed cultures. Results for the two-way MLC demonstrated that despite the weak and variable alloantigen-specific cytotoxic potential displayed by CB mononuclear cells, an immune-mediated dominance for 1 of the 2 CB units was detected in the majority of experiments. Alloantigen-induced cytotoxic activity was directed toward both CB-HP and phytohemagglutinin (PHA)-activated T lymphoblastoid cells. The CB unit with the higher fold expansion of CD34+ cells in single-expansion culture was prevalent in the HP mixed-expansion culture, as shown by DNA chimerism evaluation. Based on these data, we hypothesize that the dominant CB unit is able to develop prevalent cytotoxic activity toward activated lymphocytes of the other CB unit, thereby preventing them from exerting alloantigen-specific cytotoxic potential against both activated lymphocytes and HPs of the dominant unit. In accordance with this hypothesis, we propose the evaluation of alloantigen-induced cytotoxic activity generated in two-way MLC and directed toward PHA-activated T-lymphoblastoid cells as a tool to identify the potentially predominant CB unit before double CBT.

Early Human Herpesvirus Type 6 Reactivation after Allogeneic Stem Cell Transplantation: A Large-Scale Clinical Study - Uncorrected Proof

2012-01-03

This study investigated the impact of human herpesvirus type 6 (HHV6) reactivation within 100 days of allogeneic stem cell transplantation (allo-SCT) on patient outcomes. HHV6 plasma loads were monitored weekly by quantitative PCR. Of 235 consecutive patients, 112 (48%) had an early positive HHV6 PCR test (group A) and 123 (52%) did not (group B). HHV6 reactivation was less frequent in patients who received reduced-intensity conditioning (P = .028). In group A, only 6 patients (5%) were asymptomatic; the most common clinical manifestations were fever (n = 60), skin rash (n = 57), diarrhea (n = 51), pulmonary complications (n = 19), and neurologic disorders (n = 12). Compared with the patients in group B, those in group A experienced delayed platelet engraftment (P = .003) and more frequent grade II-IV acute graft-versus-host disease (GVHD) (47%, versus 30% in group B; P = .009). In multivariate analysis, the most important factors influencing the development of grade II-IV acute GVHD development were early HHV6 reactivation (P = .03) and unrelated donor status (P < .001). HHV6 reactivation adversely influenced 6-month survival (P = .04). Of the 38 evaluable patients receiving antiviral treatment, 34 had a significantly decreased HHV6 load. Our findings indicate that HHV6 reactivation after allo-SCT is associated with delayed platelet engraftment, early posttransplantation mortality, and the development of acute GVHD. Careful monitoring of HHV6 by PCR is warranted during the early posttransplantation period.

Role of Cytotoxic Therapy with Hematopoietic Stem Cell Transplantation in the Treatment of Pediatric Acute Lymphoblastic Leukemia: Update of the 2005 Evidence-Based Review - Uncorrected Proof

2012-01-03

Clinical research published since the first evidence-based review on the role of hematopoietic stem cell transplantation (SCT) in the treatment of pediatric acute lymphoblastic leukemia (ALL) is presented and critically evaluated in this update. Treatment recommendations are provided by an expert panel. Allogeneic SCT is recommended for children who: are in second complete remission (CR2) after experiencing an early marrow relapse for precursor-B ALL; experienced primary induction failure, but subsequently achieved a CR1; have T-lineage ALL in CR2; or have ALL in third or greater remission. Although the 2005 pediatric ALL evidence-based review (EBR) recommended allogeneic SCT for children with Philadelphia chromosome positive (Ph+) ALL in CR1, preliminary tyrosine kinase inhibitor (TKI) data demonstrate early outcomes are comparable for allogeneic SCT and chemotherapy + imatinib. Based on the evidence, autologous SCT is not recommended for ALL in CR1. Allogeneic SCT is not recommended for: T-lineage ALL in CR1; mixed-lineage leukemia (MLL)+ ALL when it is the sole adverse risk factor; isolated central nervous system (CNS) relapse in precursor-B ALL. Based on expert opinion, allogeneic SCT may be considered for hypodiploid ALL and persistent matched related donor (MRD) positivity in ALL in CR1 or greater, although these are areas which need further study. Treatment recommendations pertaining to various transplantation techniques are also provided, as are areas of needed future research.

Sequential Bortezomib, Dexamethasone, and Thalidomide Maintenance Therapy after Single Autologous Peripheral Stem Cell Transplantation in Patients with Multiple Myeloma - Uncorrected Proof

2011-12-26

We report feasibility and response results of a phase II study investigating prolonged weekly bortezomib and dexamethasone followed by thalidomide and dexamethasone as maintenance therapy after single autologous stem cell transplantation (ASCT) in patients with multiple myeloma. Within 4 to 8 weeks of ASCT, patients received weekly bortezomib and dexamethasone for six cycles, followed by thalidomide and dexamethasone for six more cycles. Thalidomide alone was continued until disease progression. Forty-five patients underwent ASCT. Forty patients started maintenance therapy; of these, 36 patients received four cycles, and 32 completed six cycles of maintenance bortezomib. Of these 40 patients, nine (22%) were in complete response (CR) before ASCT, 13 (32%) achieved CR after ASCT but before bortezomib maintenance therapy, and 21 (53%) achieved CR after bortezomib maintenance therapy. Nine patients not previously in CR (33%) upgraded their response to CR with bortezomib maintenance. At 1 year post-ASCT, 20 patients achieved CR, and two achieved very good partial response. Twenty-seven patients experienced peripheral neuropathy during bortezomib therapy, all grade 1 or 2. Our findings indicate that prolonged sequential weekly bortezomib, dexamethasone, and thalidomide maintenance therapy after single ASCT is feasible and well tolerated. Bortezomib maintenance treatment upgraded post-ASCT CR responses with no severe grade 3/4 peripheral neuropathy.

Outcome of Lower-Intensity Allogeneic Transplantation in Non-Hodgkin Lymphoma after Autologous Transplantation Failure - Uncorrected Proof

2011-12-26

We studied the outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) after lower-intensity conditioning regimens (reduced-intensity conditioning [RIC] and nonmyeloablative [NST]) in patients with non-Hodgkin lymphoma (NHL) who relapsed after autologous hematopoietic stem cell transplantation (auto-HSCT). Non-relapse mortality (NRM), lymphoma progression/relapse, progression-free survival (PFS), and overall survival (OS) were analyzed in 263 patients with NHL. All 263 patients had relapsed after a previous auto-HSCT and then had undergone allo-HSCT from a related (n = 26) or unrelated (n = 237) donor after RIC (n = 128) or NST (n = 135), and were reported to the Center for International Blood and Marrow Transplant Research between 1996 and 2006. The median follow-up of survivors was 68 months (range, 3-111 months). Three-year NRM was 44% (95% confidence interval [CI], 37%-50%). Lymphoma progression/relapse at 3 years was 35% (95% CI, 29%-41%). Three-year probabilities of PFS and OS were 21% (95% CI, 16%-27%) and 32% (95% CI, 27%-38%), respectively. Superior Karnofsky Performance Score, longer interval between transplantations, total body irradiation-based conditioning regimen, and lymphoma remission at transplantation were correlated with improved PFS. Allo-HSCT after lower-intensity conditioning is associated with significant NRM, but can result in long-term PFS. We describe a quantitative risk model based on pretransplantation risk factors to identify those patients likely to benefit from this approach.

High Incidence of Radiation-Induced Cavernous Hemangioma in Long-Term Survivors Who Underwent Hematopoietic Stem Cell Transplantation with Radiation Therapy during Childhood or Adolescence - Uncorrected Proof

2011-12-26

Radiation-induced cavernous hemangioma (RICH) is a late complication of cerebral radiation therapy. Long-term survivors of hematopoietic stem cell transplantation (HSCT) who received radiation therapy could be at increased risk for RICH. We investigated records of 68 patients who underwent HSCT during childhood or adolescence and were assessed by magnetic resonance imaging (MRI), including T2∗-weighted imaging of the brain, annually for 5 years over a range of 6-29 years after HSCT. We developed a scoring and grading system for RICH to monitor the process and the progress of radiologic changes. Among the 68 patients investigated, 28 (41.2%) were diagnosed with CH. All 28 patients had received total body irradiation as a conditioning treatment for HSCT and/or cranial radiation therapy before HSCT as part of the treatment of their primary disease. RICH was diagnosed in none of the patients who did not receive radiation (n = 19), in 46.2% of those who received 6-12 Gy (n = 39), and in all of those who received 18-36 Gy (n = 10). Total RICH scores were correlated with higher radiation doses. Careful and long-term evaluation with MRI, including T2∗-weighted imaging, is necessary for HSCT recipients who received radiation therapy before and/or during HSCT.

Graft-versus-Host Disease Prophylaxis: Does Drug Dosage Matter? - Uncorrected Proof

Gérard Socié — 2011-12-26

Acute graft-versus-host disease (aGVHD) is a common immunologic complication which occurs in 40% to 50% of the recipients of allogeneic stem cell transplantation (SCT). The immunologic events leading to injury of the target organs—skin, liver, and gut—involve activation and clonal expansion of the donor’s effector T cells in response to the recipient’s disparate major or minor histocompatibility antigens. The morbidity and mortality of this complication correlates with the severity of the organ involvement. The main treatment strategy for aGVHD routinely entails the intensification of immunosuppression which often leads to serious infectious complications. Death in patients with aGVHD is usually due to organ failure or overwhelming infections. Thus, major research efforts in allogeneic bone marrow transplantation over the past 2 decades have focused on the prevention of GVHD, mainly with pharmacologic immunosuppressive agents. Since 1985, the combination of cyclosporine (CSP) and short-course methotrexate (MTX) has been studied extensively for the prevention of aGVHD and compared to single agents such as CSP or MTX in randomized trials. This combination has been adopted as standard care in most centers .

Maximally Tolerated Busulfan Systemic Exposure in Combination with Fludarabine as Conditioning before Allogeneic Hematopoietic Cell Transplantation - Uncorrected Proof

2011-12-26

Systemic exposure to high-dose busulfan has been correlated with efficacy and toxicity after hematopoietic cell transplantation for malignancy. We used the area under the concentration-time curve (AUC) to prospectively determine the maximally tolerated systemic exposure to intravenous (IV) busulfan when given once daily after fludarabine administered at 40 mg/m2 for 4 days. Three target AUC levels were planned: 6000, 7500, and 9000 μM-min. Included were patients 16 to 65 years old, with a hematologic malignancy, an HLA A, B, or C, DRB1 8/8 or 7/8 matched donor, Karnofsky performance status ≥70%, and adequate organ function. For level 1 patients, IV busulfan doses 1 and 2 were 170 mg/m2/day, then doses 3 and 4 were adjusted based on first dose pharmacokinetic modeling to achieve an average daily AUC of 6000 μM-min. Doses 1 and 2 for the subsequent cohorts were based on the level 1 data: 180 mg/m2/day for AUC 7500 μM-min (level 2) and 220 mg/m2/day for AUC 9000 μM-min (level 3), with pharmacokinetic targeting for doses 3 and 4. Pharmacokinetic analysis after the last dose showed that 88% of the patients had been exposed to a mean AUC within 10% of the target. Forty patients were treated at level 1, 29 patients at level 2, and 3 patients at level 3. DLT was veno-occlusive disease of the liver, which occurred in none of 40 patients (0%) at level 1, 2 of 29 patients (7%) at level 2, and 3 of 3 patients (100%) at level 3. Dermatitis (P < .01) and pulmonary toxicity (P = .01) were also increased at higher AUC levels. Level 2 (7500 μM-min × 4 days) was the maximally tolerated AUC. Within the confines of the trial’s small sample size, there was no suggestion that escalating busulfan AUC from 6000 to 7500 μM-min × 4 days increased nonrelapse mortality. Assessment of the higher busulfan AUC on relapse prevention requires trials in patients with a homogeneous risk of relapse.

High White Blood Cell Concentration in the Peripheral Blood Stem Cell Product Can Induce Seizures during Infusion of Autologous Peripheral Blood Stem Cells - Uncorrected Proof

2011-12-19

Seizures as a complication of the infusion of autologous peripheral blood stem cells (PBSC) are rare. Seizures during infusion of autologous PBSC in 3 of our patients prompted us to review our cell therapy and cytapheresis protocols and procedures. We retrospectively analyzed 159 adult patients collected between January 2006 and July 2009. Patients were collected on either COBE Spectra cell separator (n = 85) or Fresenius AS 104 cell separator (n = 74) and mobilized with granulocyte colony stimulating factor (G-CSF) alone (n = 47), G-CSF and Plerixafor (n = 36), or G-CSF and chemotherapy (n = 76). Patient characteristics (including age, weight, number of collections, volume processed, disease type, and mobilization strategy) did not differ significantly between the COBE and Fresenius cohorts, and adverse effects from infusion were similar except for 3 of 159 patients who experienced seizures upon infusion of PBSC; all 3 were collected on the COBE and had PBSC product white blood cell (WBC) counts of 590 × 103/μL or above. We prospectively correlated WBC counts midcollection, with final WBC counts to identify products with high WBC concentration during cytapheresis. Fifty-one patients had 66 cytapheresis procedures using the COBE, with WBC counts midway and at the end of collection of 287 × 103 ± 150/μL and 273 × 103 ± 144/μL, respectively. Mid-WBC therefore correlated with WBC at the end of the collection. Finally, we prospectively collected mid-WBC from 65 patients who underwent 80 PBSC collections between June 2009 and January 2010 to identify products with midcollection WBC concentration >450 × 103/μL. In those cases, additional autologous plasma was collected at the time of collection to dilute the final product before cryopreservation. Patients who received diluted products experienced no delays in engraftment and no additional seizure episodes occurred.

Everolimus in Combination with Cyclosporin A as Pre- and Posttransplantation Immunosuppressive Therapy in Nonmyeloablative Allogeneic Hematopoietic Stem Cell Transplantation - Uncorrected Proof

2011-12-19

Everolimus (RAD001) is an mTOR inhibitor that has been successfully used as an immunosuppressant in solid-organ transplantation. Data in allogeneic hematopoietic stem cell transplantation (HSCT) is limited. This study aimed to investigate pharmacokinetics, safety, and efficacy of RAD001 in a canine allogeneic HSCT model. First, pharmacokinetics of RAD001 were performed in healthy dogs in order to determine the appropriate dosing. Doses of 0.25 mg RAD001 twice daily in combination with 15 mg/kg cyclosporin A (CsA) twice daily were identified as appropriate starting doses to achieve the targeted range of RAD001 (3-8 μg/L) when orally administered. Subsequently, 10 dogs were transplanted using 2 Gy total body irradiation (TBI) for conditioning and 0.25 mg RAD001 twice daily plus 15 mg/kg CsA twice daily for pre- and posttransplantation immunosuppression. Seven of the 10 transplanted dogs were maintained at the starting RAD001 dose throughout the study. For the remaining 3 dogs, dose adjustments were necessary. RAD001 accumulation over time did not occur. All dogs initially engrafted. Five dogs eventually rejected the graft (weeks 10, 10, 13, 27, and 56). Two dogs died of pneumonia (weeks 8 and 72) but were chimeric until then. Total cholesterol rose from median 4.1 mmol/L (3.5-5.7 mmol/L) before HSCT to 6.0 mmol/l (5.0-8.5 mmol/l) at day 21 after HSCT, but remained always within normal range. Changes in creatinine and triglyceride values were not observed. Long-term engraftment rates were inferior to sirolimus/CsA and mycophenolate mofetil (MMF)/CsA regimen, respectively. RAD001/CsA caused a more pronounced reduction of platelet counts to median 2 × 109/L (range: 0-21 × 109/L) and longer time to platelet recovery of 21 days (range: 14-24 days) compared with MMF/CsA. CsA c2h levels were significantly enhanced in the RAD001/CsA regimen, but c0h and area under the curve from 0 to 12 hours (AUC0-12h) values did not differ compared with an MMF/CsA immunosuppression. In summary, immunosuppression consisting of RAD001 and CsA is well tolerated but not as efficient as with other established immunosuppressants in a canine nonmyeloablative HSCT regimen. Hence, our study does not support the application of RAD001/CsA as standard practice in this setting.

Inhibition of Cathepsin S Reduces Allogeneic T Cell Priming but Not Graft-versus-Host Disease Against Minor Histocompatibility Antigens - Uncorrected Proof

2011-12-16

Cathepsin (Cathepsin) S, L, and B proteases mediate antigen presentation on major histocompatibility complex (MHC) class II by degrading the invariant chain Ii, which blocks peptide loading. The ability of the Cathepsin S inhibitor LHVS (morpholinurea-leucine-homophenylalanine-vinylsulfone phenyl) to impede antigen presentation has led its development as a therapy for autoimmune diseases. There is substantial evidence that donor T cell recognition of host minor histocompatibility antigens (miHA) and subsequent destruction of host tissue mediates graft-versus-host disease (GVHD). We hypothesized that enzymes involved in antigen presentation may play a role in the development of GVHD. Using the C57BL/6 → BALB.B minor mismatch acute GVHD (aGVHD) model, we found that the cathepsin S activity of spleens from allogenetically transplanted mice were significantly increased 1 week after transplantation compared with syngeneic mice. Although LHVS decreased T cell priming responses against both single OVA antigen and miHA in vitro, LHVS did not reduce the severity of aGVHD. In fact, LHVS exacerbated a CD4+-T cell-dependent model of GVHD similar to chronic GVHD. This suggests that cytokines rather than T cells may mediate much of the damage in the aGVHD model and that therapeutics based on inhibition of antigen presentation for GVHD must be approached with caution.

Genetic Variation in Donor CTLA-4 Regulatory Region is a Strong Predictor of Outcome after Allogeneic Hematopoietic Cell Transplantation for Hematologic Malignancies - Uncorrected Proof

2011-12-15

Relapse remains a major cause of death after allogeneic hematopoietic cell transplantation (allo-HCT). Graft-versus-tumor effect is primarily mediated by donor T cells. Cytotoxic T lymphocyte antigen-4 (CTLA-4) is a critical inhibitor of T cell proliferation. Single nucleotide polymorphisms (SNPs) in CTLA-4 may affect immune responses. We hypothesized that CTLA-4 SNPs will be associated with disease control after allo-HCT. One hundred sixty-four adult patients with the availability of pretransplant recipient and donor DNA samples were included in this analysis. Ten tagSNPs of the CTLA-4 gene were identified. Donor CTLA-4 SNP rs4553808 was associated with decreased relapse-free survival (RFS) (P = .019) and overall survival (OS) (P = .033). In multivariable analysis of additive genetic model, genotype of CTLA-4 SNP rs4553808 was an independent risk factor for inferior RFS (hazard ratio [HR] = 1.73, 95% confidence interval [CI] 1.10-2.71, P = .017) and OS (HR = 1.84, 95% CI 1.13-3.0, P = .015). CTLA-4 SNPs can be used to identify high risk patient subsets that may benefit from preemptive immunomodulation to decrease relapse rates and improve survival.

Recommended Screening and Preventive Practices for Long-Term Survivors after Hematopoietic Cell Transplantation - Uncorrected Proof

2011-12-15

Advances in hematopoietic cell transplantation (HCT) technology and supportive care techniques have led to improvements in long-term survival after HCT. Emerging indications for transplantation, introduction of newer graft sources (eg, umbilical cord blood) and transplantation of older patients using less intense conditioning regimens have also contributed to an increase in the number of HCT survivors. These survivors are at risk for developing late complications secondary to pre-, peri-, and posttransplantation exposures and risk factors. Guidelines for screening and preventive practices for HCT survivors were published in 2006. An international group of transplantation experts was convened in 2011 to review contemporary literature and update the recommendations while considering the changing practice of transplantation and international applicability of these guidelines. This review provides the updated recommendations for screening and preventive practices for pediatric and adult survivors of autologous and allogeneic HCT.

Successful Remission Rates and Survival after Lymphodepleting Chemotherapy and Donor Lymphocyte Infusion for Relapsed Hematologic Malignancies Postallogeneic Hematopoietic Cell Transplantation - Corrected Proof

2011-12-12

Few therapeutic strategies exist for hematologic malignancies relapsing post allogeneic hematopoietic cell transplantation. We present outcomes on 35 patients with nonchronic myelogenous leukemia (CML) hematologic malignancies, the majority having acute myelogenous leukemia (AML) or myelodysplastic syndromes/myeloproliferative disorders (MDS/MPD) (n = 22) receiving lymphodepleting chemotherapy followed by donor lymphocyte infusion (DLI) at 2 T cell dose levels (0.5 and 1.0 × 108 CD3/kg). Forty-nine percent of patients achieved complete remission (CR), with a median duration of remission of 6 months (range: 2-71+). CR rates were similar between the 2 groups. The incidence of acute graft-versus-host disease (aGVHD) of any grade was 49%. We saw a higher incidence of grade II-IV aGVHD, with a rate of 66% using the higher-dose DLI (grade III, 33% and grade 4, 20%) versus only 25% (10% grade III-IV) with the lower-dose DLI (P = .06). Overall survival at 1 and 2 years was 30% (95% confidence interval [CI], 16%-45%) and 19% (95% CI, 8%-34%); however, for those achieving CR, 1- and 2-year survival was improved at 44% (95% CI, 20%-66%) and 28% (95% CI, 8%-52%) (P = .03), respectively. These results demonstrate that DLI after lymphodepleting chemotherapy for relapsed hematologic malignancies results in frequent CRs. The lower DLI dose regimen improved the tolerability of this therapeutic approach, with modest rates of severe aGVHD.

Soluble Tumor Necrosis Factor Receptor: Enbrel (Etanercept) for Subacute Pulmonary Dysfunction Following Allogeneic Stem Cell Transplantation - Uncorrected Proof

2011-12-12

Subacute lung disease, manifested as either obstructive (OLD) or restrictive (RLD) lung dysfunction, is a common complication following allogeneic stem cell transplantation. In each case, therapeutic options are limited, morbidity remains high, and long-term survival is poor. Between 2001 and 2008, 34 patients with noninfectious, obstructive (25) or RLD restrictive lung dysfunction (nine) received etanercept (Enbrel®, Amgen Inc.) 0.4 mg/kg/dose, subcutaneously, twice weekly, for 4 (group A) or 12 weeks (group B). Corticosteroids (if present at study entry) were kept constant for the initial 4 weeks of therapy and then tapered as tolerated. Thirty-one of 34 (91%) subjects were evaluable for response, and 10 (32%) met primary response criteria. There was no difference in response based on the duration of treatment (29% group A versus 35% group B; P = .99), the presence of RLD or OLD (33% versus 32%; P = .73), or the severity of pulmonary disease at study onset. Estimated 5-year overall survival rates following therapy were 61% (95% confidence interval, 46%-80%) for all subjects and 90% (95% confidence level, 73%-100%) for the 10 who met the primary response criteria. Five-year survival estimates for subjects treated with RLD was 44%, compared with 67% for those treated for OLD (P = .19). Etanercept was well tolerated, with no bacteremia or viremia observed. Pathogens were noted on posttherapy bronchoalveolar lavage in two cases. These data support the development of expanded clinical trials to study etanercept as a therapeutic agent for subacute lung injury after allogeneic stem cell transplantation.

Natural Killer Cell Differentiation from Hematopoietic Stem Cells: A Comparative Analysis of Heparin- and Stromal Cell–Supported Methods - Uncorrected Proof

2011-12-08

Natural killer (NK) cells differentiated from hematopoietic stem cells (HSCs) may have significant clinical benefits over NK cells from adult donors, including the ability to choose alloreactive donors and potentially more robust in vivo expansion. Stromal-based methods have been used to study the differentiation of NK cells from HSCs. Stroma and cytokines support NK cell differentiation, but may face considerable regulatory hurdles. A recently reported clinical-grade, heparin-based method could serve as an alternative. How the stromal-based and heparin-based approaches compare in terms of NK cell generating efficiency or function is unknown. We show that compared with heparin-based cultures, stroma significantly increases the yield of HSC-derived NK cells by differentiating less-committed progenitors into the NK lineage. NK cells generated by both approaches were similar for most NK-activating and -inhibiting receptors. Although both approaches resulted in a phenotype consistent with CD56bright stage IV NK cells, heparin-based cultures favored the development of CD56+CD16+ cells, whereas stroma produced more NK cell immunoglobulin-like receptor–expressing NK cells, both of which are markers of terminal maturation. At day 21, stromal-based cultures demonstrated significantly more IL-22 production, and both methods yielded similar amounts of IFN-γ production and cytotoxicity by day 35. These findings suggest that heparin-based cultures are an effective replacement for stroma and may facilitate clinical trials testing HSC-derived NK cells.

T Cell-Depleted Partial Matched Unrelated Donor Transplant for Advanced Myeloid Malignancy: KIR Ligand Mismatch and Outcome - Uncorrected Proof

2011-12-08

To evaluate the applicability of high-dose conditioning, CD34 selection, and enhanced natural killer (NK) cell alloreactivity reported as promising after haploidentical transplantation, we tested the same strategy for patients with advanced/high-risk myeloid leukemia lacking either related or well-matched unrelated donors (URD). In a prospective multicenter clinical trial using pretransplant conditioning of thiotepa (5 mg/kg/day × 2), fludarabine (40 mg/mg/M2/day × 5), and total-body radiation (800 cGy) plus thymoglobulin (2.5 mg/kg/day × 2), and a CD34 selected filgrastim stimulated peripheral blood graft from a partial matched URD, we treated 24 patients. The patients (median age 40 [range: 22-61]) were mismatched at 1-3 of 10 HLA loci with their donors; all were mismatched at HLA-C. Thirty-seven percent were ethnic or racial minorities. Twenty-one of 24 engrafted promptly with 1 primary graft failure and 2 early deaths. The cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) (34%, 95% confidence interval [CI], 14-54%), chronic GVHD (20%, 95% CI, 2%-38%) and relapse (26%, 95% CI, 8%-84%) were unaffected by KIR ligand donor:recipient mismatch (n = 5) versus KIR ligand match (n = 19). Only 3 (12%) had grade III-IV GVHD. Nonrelapse occurred in 17% (95% CI, 30%-31%) by 100 days and 35% (95% CI, 15%-55%) by 1 year. Two-year survival and leukemia-free survival were each 40% (95% CI, 21%-59%) and was similar in KIR ligand matched or mismatched patients. Infections, mostly in the first 2 months, were frequent, and were the cause of death in 5 patients (35% of deaths). T cell recovery and NK cell proliferation and functional maturation were not altered by KIR ligand match or mismatch status. For these high-risk patients, this high intensity regimen and T depleted approach yielded satisfactory outcomes, but logistical difficulties in arranging URD grafts for patients with high risk, unstable leukemia limited accrual. Improvements in peritransplant disease control and additional measures to augment the allogeneic graft versus leukemia effect are still required.

Highly Variable Pharmacokinetics of Once-Daily Intravenous Busulfan When Combined with Fludarabine in Pediatric Patients: Phase I Clinical Study for Determination of Optimal Once-Daily Busulfan Dose Using Pharmacokinetic Modeling - Uncorrected Proof

2011-12-08

Busulfan has a narrow therapeutic range, and in children, pharmacokinetic variability has been found to be high even after the use of intravenous (i.v.) busulfan. Recently, a reduced toxicity myeloablative regimen showed promising results, but the data of busulfan pharmacokinetics in hematopoietic stem cell transplantation (HSCT) using a targeted busulfan/fludarabine regimen in children has not yet been reported. We performed therapeutic drug monitoring (TDM) after once-daily i.v. busulfan combined with fludarabine and analyzed the outcomes. Busulfan (i.v.) was administered once daily for 4 consecutive days. The daily target area under the curve (AUC) was 18,125-20,000 μg∗h/L/day (4415-4872 μmol∗min/L/day), which was reduced to 18,000-19,000 μg∗h/L/day (4384-4628 μmol∗min/L/day) after a high incidence of toxicity was observed. A total of 24 patients were enrolled. After infusion of busulfan on the first day, patients showed AUC that ranged from 12,079 to 31,660 μg∗h/L (2942 to 7712 μmol∗min/L) (median 16,824 μg∗h/L, percent coefficient of variation (%CV) = 26.5%), with clearance of 1.74-6.94 mL/min/kg (median 4.03 mL/min/kg). We performed daily TDM in 20 patients, and during the daily TDM, the actual AUC ranged from 73% to 146% of the target AUC, showing high intraindividual variability. The %CV of busulfan clearance of each individual ranged from 7.7% to 38.7%. The total dose of busulfan administered for 4 days ranged from 287.3 mg/m2 to 689.3 mg/m2. Graft failure occurred in 3 patients with total AUC less than 74,000 μg∗h/L (18,026 μmol∗min/L), and 2 patients with relatively high total AUC experienced veno-occlusive disease. Busulfan pharmacokinetics showed high inter- and intraindividual variability in HSCT using a targeted busulfan/fludarabine regimen, which indicates the need for intensive monitoring and dose adjustment to improve the outcome of HSCT. Currently, we are performing a newly designed phase II study to decrease regimen-related toxicities and reduce graft failure by setting an optimal target AUC based on this study.

Alternate Donor Hematopoietic Cell Transplantation (HCT) in Non-Hodgkin Lymphoma Using Lower Intensity Conditioning: A Report from the CIBMTR - Uncorrected Proof

2011-12-08

We analyzed the outcomes of 248 (61% male) adult recipients of HLA-matched unrelated and HLA-mismatched related donor hematopoietic cell transplantation (HCT) for non-Hodgkin lymphoma (NHL) after reduced or lower intensity conditioning (RIC), reported to the Center for International Blood and Marrow Transplant Research (CIBMTR) from 1997 to 2004. Median age was 52 (range: 18-72 years); 31% had a Karnofsky performance score <90. Follicular NHL (43%) was the major histology. Incidence of grades II-IV acute graft-versus-host disease (aGVHD) was 43% at 100 days; and chronic GVHD (cGVHD) was 44% at 3 years. Treatment-related mortality (TRM) at 100 days was 24%. Three-year overall survival (OS) and progression-free survival (PFS) were 41% and 32%, respectively. In multivariate analysis, use of antithymocyte globulin (ATG) and HLA mismatch were associated with increased TRM. High-grade histology, ATG use, and chemotherapy resistance were associated with lower PFS. Older age, shorter interval from diagnosis to HCT, non–total body irridiation (TBI) conditioning regimens, ex vivo T cell depletion, and HLA-mismatched unrelated donors were associated with mortality. GVHD did not influence relapse or PFS. Older age, aggressive histology, and chemotherapy resistance correlated with poorer survival. For selected patients with NHL, lack of an available sibling donor should not be a barrier to allogeneic HCT.

Tandem Autologous–Allogeneic Nonmyeloablative Sibling Transplantation in Relapsed Follicular Lymphoma Leads to Impressive Progression-Free Survival with Minimal Toxicity - Uncorrected Proof

2011-12-08

Autologous stem cell transplantation (ASCT) prolongs survival in patients with relapsed follicular lymphoma. ASCT is usually not curative, however. Myeloablative allogeneic transplantation has produced long-term survival at a cost of significant transplantation-related mortality (TRM), whereas reduced-intensity transplantation entails less TRM but has a higher relapse rate. We thus initiated a protocol consisting of ASCT followed by nonmyeloablative allogeneic transplantation (NMT) for relapsed follicular lymphoma to mimic myeloablative allogeneic transplantation without the associated toxicity. The NMT was non–T cell-depleted, and all donors were HLA-identical siblings. We report results in 27 patients with a median age of 49 years (range, 34-65 years). Five patients demonstrated histological progression toward an aggressive lymphoma. The patients had received a median of 3 lines of previous therapy. Disease status before ASCT included 8 patients in complete remission, 14 in partial remission, and 5 refractory. Five patients developed grade II-IV acute graft-versus-host disease, and 20 patients developed chronic graft-versus-host disease requiring systemic therapy. With a median follow-up of 39 months after NMT, overall survival and progression-free survival were 96% at 3 years. We conclude that the combined ASCT-NMT strategy appears to be safe, with excellent progression-free survival even in refractory and transformed cases. This novel approach warrants further investigation in larger prospective studies.

Important Drug Interactions in Hematopoietic Stem Cell Transplantation: What Every Physician Should Know - Uncorrected Proof

2011-12-08

Abstract: Morbidity is increased in patients undergoing hematopoietic stem cell transplantation when drug–drug interactions lead to unexpected outcomes. These interactions occur as a result of exposure to complicated medical regimens with drugs with narrow therapeutic windows and high toxicity profiles. In this report, we review the available evidence and possible mechanisms of the most clinically relevant drug interactions, including those involving inhibitors and inducers of the P450 isoenzyme system. We identify key interactions that should be familiar to any physician caring for patients after hematopoietic stem cell transplantation. We discuss drug metabolism in children and in the elderly and examine how age-related differences in metabolism make complicate drug regimens in these populations. A better understanding of these interactions and the responsible mechanisms will promote efficient delivery of the safest medical regimens to patients undergoing hematopoietic stem cell transplantation.

Impact of Bone Marrow Hematogones on Umbilical Cord Blood Transplantation Outcomes in Patients with Acute Myeloid Leukemia - Corrected Proof

2011-11-21

Early after umbilical cord blood transplantation, patients show marked differences in bone marrow (BM) hematogone percentages. Little is known about whether these differences are clinically relevant. We hypothesized that early recovery of hematogones may be associated with improved transplantation outcomes. BM aspirates were assessed from 88 patients with acute myeloid leukemia by two independent reviewers at day 21 and 100 after umbilical cord blood transplantation. Interobserver variability for BM hematogone percentages at these time points showed correlation coefficients of 0.83 and 0.98, respectively (P ≤ .01 for both). A high percentage of hematogones at day 21 was associated with less acute graft-versus-host disease grade 3 to 4 (P = .01). At day 100, a high percentage of BM hematogones was associated with improved overall survival (P = .02) and lower treatment-related mortality (P ≤ .01). This study shows that BM hematogone percentages may be useful prognostic indicators in patients with acute myeloid leukemia after umbilical cord blood transplantation and should be routinely reported in BM differential counts.

Marrow versus Blood-Derived Stem Cell Grafts for Allogeneic Transplantation from Unrelated Donors in Patients with Active Myeloid Leukemia or Myelodysplasia - Corrected Proof

2011-11-21

Peripheral blood stem cells (PBSCs) are increasingly used as the graft source in allogeneic hematopoietic cell transplantation. We compared long-term outcome after unrelated donor transplantation of 85 consecutive patients with acute myelogenous leukemia or myelodysplastic syndrome regarding disease status (early disease [CR1, refractory anemia); n = 25 and advanced/active disease [>CR1, >refractory anemia]; n = 60) who were treated with conventional conditioning regimens followed by bone marrow (BM) or PBSC grafts. Graft-versus-host disease prophylaxis consisted mainly of cyclosporine A, short-course methotrexate, and anti-T-lymphocyte globulin. After a median follow-up of 118 months (68-174), the 10-year event-free survival rate after peripheral blood stem cell transplantation (PBSCT) was 54.8% (95% confidence interval [CI], 39.7%-69.8%), and after bone marrow transplantation (BMT), it was 27.9% (14.5%-41.3%; P < .004). In the advanced/active disease group, the 10-year event-free survival rate after PBSCT was 50% (30.8%-69.2%), and after BMT, it was 23.5% (9.3%-37.8%; P < .007). Non relapse mortality was less after PBSCT than BMT (14.3% vs 30.2%), respectively. In multivariate Cox regression analysis, PBSCT showed a better overall survival (OS; hazard ratio [HR], 0.43; 95% CI, 0.23-0.79; P = .007) compared to BMT; unfavorable/unknown prognostic impact cytogenetic abnormalities were an adverse factor for all patients (HR, 2.202; 95% CI, 1.19-4.06; P = .011). In patients with advanced disease, the use of PBSCs showed a significant favorable outcome via multivariate analysis (HR, 0.49; 95% CI, 0.24-0.99; P = .046). Outcome of acute myelogenous leukemia/myelodysplastic syndrome after unrelated hematopoietic cell transplantation is adversely affected by cytogenetic abnormalities and state of remission at hematopoietic cell transplantation. PBSC as a graft source has a significant favorable influence on survival.

The Triterpenoid CDDO-Me Promotes Hematopoietic Progenitor Expansion and Myelopoiesis in Mice - Corrected Proof

Erik Ames, Salif Harouna, Colin Meyer, Lisbeth A. Welniak, William J. Murphy — 2011-11-18

The synthetic triterpenoid CDDO-Me has been shown to directly inhibit the growth of myeloid leukemias and lends itself to a wide array of therapeutic indications, including inflammatory conditions, because of its inhibition of NF-κB. We have previously demonstrated protection from acute graft-versus-host disease after CDDO-Me administration in an allogeneic bone marrow transplantation model. In the current study, we observed that CDDO-Me promoted myelopoiesis in both naive and transplanted mice. This effect was dose dependent, as high doses of CDDO-Me inhibited myeloid growth in vitro. All lineages (granulocyte macrophage colony-forming unit, BFU-E) were promoted by CDDO-Me. We then compared the effects with granulocyte colony-stimulating factor, a known inducer of myeloid expansion and mobilization from the bone marrow. Whereas both drugs induced terminal myeloid expansion in the spleen, peripheral blood, and bone marrow, granulocyte colony-stimulating factor only induced granulocyte macrophage colony-forming unit precursors in the spleen, while CDDO-Me increased these precursors in the spleen and bone marrow. After sublethal total-body irradiation, mice pretreated with CDDO-Me further displayed an accelerated recovery of myeloid progenitors and total nucleated cells in the spleen. A similar expansion of myeloid and myeloid progenitors was noted with CDDO-Me treatment after syngeneic bone marrow transplantation. Combined, these data suggest that CDDO-Me may be of use posttransplantation to accelerate myeloid recovery in addition to the prevention of graft-versus-host disease.

Impact of a Conservative Red Blood Cell Transfusion Strategy in Children Undergoing Hematopoietic Stem Cell Transplantation - Corrected Proof

2011-11-14

A 2008 randomized trial of critically ill, but stable, children reported the safety of transfusing red blood cells at a hemoglobin threshold of 7 g/dL. In 2009, we adopted the same transfusion criteria in our hematopoietic stem cell transplantation patients. Regression modeling was used to compare data obtained during primary admission for hematopoietic stem cell transplantation in calendar years before and after our practice change. Sixty-six patients admitted in the preintervention year were compared with 75 postintervention. Pre- and postpatients were similar in diagnoses and type of transplantations. Postintervention, median hemoglobin pretransfusion significantly decreased from 8.8 g/dL to 6.8 g/dL (P < .0001). In addition, transfused red blood cell units received by patients dropped from 4 (interquartile range [IQR] 3, 8) to 3 (IQR, 2, 5), (P = .002), and number of transfusion days per patients decreased from 4 (IQR, 2,5) to 3 (IQR, 2, 5), (P = .01). There were no differences in length of stay, time to engraftment, or 100-day mortality. Median blood product charges per patient significantly decreased ($3,624 [IQR, $2,265, $6,040] to $2,185 [IQR, $1,812, $3,997], P = .004). Our initial experience suggests that implementation of a conservative transfusion strategy in otherwise stable children undergoing hematopoietic stem cell transplantation appears safe and lowers transfusion exposures.

Allogeneic Hematopoietic Stem Cell Transplantation for Pediatric Patients with Treatment-Related Myelodysplastic Syndrome or Acute Myelogenous Leukemia - Corrected Proof

2011-11-11

The development of treatment-related myelodysplastic syndrome (tMDS) or treatment-related acute myelogenous leukemia (tAML) is a complication that can occur after chemotherapy or radiation therapy. Eighteen patients with a previous malignancy treated at our institution and three patients with a nonmalignant primary tumor received an allogeneic hematopoietic stem cell transplant (HSCT) on the pediatric bone marrow (BM) transplantation service for the treatment of tMDS/tAML over a 15-year period. Five patients proceeded to HSCT without induction chemotherapy. Fourteen patients received high-dose cytarabine according to the Capizzi II regimen as first-line induction therapy with 13 of them achieving complete remission (CR) or refractory anemia (RA) with persistent cytogenetic abnormalities after this treatment. Two patients received an anthracycline-based induction therapy. Conditioning regimens were selected according to previous therapies: 11 patients received busulfan-melphalan-fludarabine (BU-MEL-FLU), which consisted of busulfan (0.8 mg/kg/dose every 6 hours ×10 doses), melphalan (70 mg/m2/dose × two doses), and fludarabine (25 mg/m2/dose × five doses) for cytoreduction; three patients received a total body irradiation (TBI)-containing regimen; seven patients received myeloablative regimens containing busulfan and/or melphalan and/or thiotepa with doses modified for organ toxicity. Sixteen patients received T cell-depleted (TCD) grafts; four patients received unmodified grafts; one patient received a double-unit cord blood transplantation (DUCBT). Donors included HLA-matched (n = 9), or mismatched (n = 3) related donors, or HLA-matched (n = 4), or mismatched (n = 4) unrelated donors, or DUCBT (n = 1). Disease status at the time of HSCT was: morphologic and cytogenetic CR (n = 12); RA with positive cytogenetics (n = 6); and refractory disease (n = 3). With a median follow-up of 5.9 years (2.2-15.7 years), the 5-year overall survival (OS) and disease-free survival (DFS) rates for the entire group were 61.1% with 12 patients alive without evidence of either primary disease or tMDS/tAML. The OS and DFS rate for the 11 patients who received the BU-MEL-FLU cytoreduction with TCD grafts was 54.5%. DFS was 65.7% for patients in RA or CR at HSCT compared with 0% for patients with >5% residual marrow blasts (P = .015). Nine patients died; the cause of death was relapse of MDS/AML (n = 4) or primary disease (n = 2), graft-versus-host disease (GVHD; n = 2), and infection (n = 1). Four patients developed grade II to IV acute GVHD. One patient developed localized chronic GVHD. Our results suggest that the strategy of induction with high-dose cytarabine therapy followed by allogeneic stem cell transplantation improves the overall outcome for patients with tMDS/tAML. In addition, the use of a TCD transplantation with BU-MEL-FLU as cytoreduction may decrease the toxicity of transplantation in heavily pretreated patients without an increase in relapse rate.

Phase I-II Study of Clofarabine-Melphalan-Alemtuzumab Conditioning for Allogeneic Hematopoietic Cell Transplantation - Corrected Proof

2011-11-10

We conducted a phase I-II study of transplantation conditioning with clofarabine-melphalan-alemtuzumab for patients with advanced hematologic malignancies. Ten patients were accrued to the phase I portion, which utilized an accelerated titration design. No dose-limiting toxicity was observed, and clofarabine 40 mg/m2 × 5, melphalan 140 mg/m2 × 1, and alemtuzumab 20 mg × 5 was adopted for the phase II study, which accrued 72 patients. Median age was 54 years. There were 44 patients with acute myelogenous leukemia or myelodysplastic syndromes, 27 with non-Hodgkin lymphoma, and nine patients with other hematologic malignancies. The largest subgroup of 35 patients had American Society for Blood and Marrow Transplantation high-risk, active disease. All evaluable patients engrafted with a median time to neutrophil and platelet recovery of 10 and 18 days, respectively. The cumulative incidence of treatment-related mortality was 26% at 1 year. Cumulative incidence of relapse was 29% at 1 year. Overall survival was 80% (95% confidence interval [CI], 71-89) at 100 days and 59% (95% CI, 47-71) at 1 year. Progression-free-survival was 45% (95% CI, 33-67) at 1 year. Rapid-onset renal failure was the main toxicity in the phase II study and more frequent in older patients and those with baseline decrease in glomerular filtration rate. Grade 3-5 renal toxicity was observed in 16 of 74 patients (21%) treated at the phase II doses. Clofarabine-melphalan-alemtuzumab conditioning yields promising response and duration of response, but renal toxicity poses a considerable risk particularly in older patients.

Significance of Increased Blastic-Appearing Cells in Bone Marrow Following Myeloablative Unrelated Cord Blood Transplantation in Adult Patients - Corrected Proof

2011-11-10

An abnormal increase of nonleukemic blastic-appearing lymphocytes in bone marrow (BM) specimens has been reported after unrelated cord blood transplantation (UCBT). This study analyzed the incidence, chronology, biological features, and clinical significance of elevated numbers of these cells in a series of 165 consecutive adult patients demonstrating myeloid engraftment after myeloablative UCBT in a single institution. The patients’ BM samples were routinely evaluated by cytomorphology at different time points after UCBT. When ≥5% of blastic-appearing cells were detected by cytomorphology in the BM, samples were also evaluated by multiparametric flow cytometry to characterize these cells. Systematic chimerism analyses of BM samples using PCR amplification of short tandem repeat markers were performed. Forty-three patients (cumulative incidence, 26.1%) demonstrated ≥5% of nonmalignant blastic-appearing cells in BM after a median of 101 days after UCBT (range, 28-377 days). All of these patients had full-donor chimerism and a clinical course without leukemic relapse. Multiparametric flow cytometry analyses performed in 36 of the 43 patients showed a polyclonal expansion of B lymphocytes with a broad spectrum of maturation stages. An increased number of nonmalignant blastic-appearing cells was significantly associated with a high number of lymphocytes infused at the time of UCBT and with low rates of acute and chronic extensive graft-versus-host disease, suggesting a potential immunoregulatory role of these cells. The observation of ≥5% nonmalignant blastic-appearing cells in BM samples after myeloablative UCBT is frequent, and these should be distinguished from malignant blasts.

Evaluation of Oral Beclomethasone Dipropionate for Prevention of Acute Graft-versus-Host Disease - Corrected Proof

2011-11-10

Results from two randomized trials have shown that oral beclomethasone dipropionate (BDP) is effective for treatment of acute gastrointestinal graft-versus-host disease. Here, we report results of a double-blind, randomized placebo-controlled phase II study designed to test the hypothesis that acute graft-versus-host disease could be prevented by administration of oral BDP, beginning before hematopoietic cell transplantation and continuing until day 75 after hematopoietic cell transplantation after myeloablative conditioning. Study drug (BDP or placebo) was administered as 1-mg immediate-release formulation plus 1-mg delayed-release formulation orally four times daily. According to the primary endpoint, systemic glucocorticoid treatment for graft-versus-host disease was given to 60 of the 92 participants (65%) in the BDP arm, versus 31 of 46 participants (67%) in the placebo arm. The secondary efficacy endpoints showed no statistically significant differences between the two arms. The proportion of participants who took at least 90% of the prescribed study drug during the first 4 weeks after hematopoietic cell transplantation was 54% overall. Lower severity of mucositis strongly correlated with higher adherence to the schedule of study drug administration. Inconsistent adherence related to mucositis during recovery after myeloablative conditioning may have obscured a beneficial therapeutic effect in the current study.

Risk Factors for Progression from Cytomegalovirus Viremia to Cytomegalovirus Disease after Allogeneic Hematopoietic Stem Cell Transplantation - Corrected Proof

2011-11-07

Cytomegalovirus (CMV) disease is a major cause of infectious complications in allogeneic hematopoietic stem cell transplantation (allo-HSCT). Although patients undergoing allo-HSCT receive prophylactic and preemptive treatment for CMV, a subset of patients experience clinically significant CMV disease. This study investigated the risk factors for progression from CMV viremia to CMV disease during or after preemptive therapy in patients undergoing allo-HSCT. Between January 2006 and August 2010, 43 patients received preemptive therapy for CMV viremia after allo-HSCT. These patients experienced 74 episodes of CMV viremia. Nine of the patients (21%) and 12 of the episodes (16%) progressed to CMV disease. Univariate analysis identified several risk factors for progression to CMV disease, including high initial viral load (P = .020), leukopenia (P = .012), and neutropenia (P = .033) at the time of detection of CMV viremia. On multivariate analysis, leukopenia remained an independent predictor (hazard ratio, 4.347; P = .045). The rate of failure to clear CMV viremia after 1 cycle of preemptive therapy was higher in the leukopenia group than in the non-leukopenia group (60.0% versus 16.9%; P = .002). This indicates that leukopenia initially documented with CMV viremia is related to lower viral response to preemptive therapy and is a notable risk factor for progression from CMV viremia to CMV disease.

In Situ Detection of HY-Specific T Cells in Acute Graft-versus-Host Disease–Affected Male Skin after Sex-Mismatched Stem Cell Transplantation - Corrected Proof

2011-11-07

HY-specific T cells are presumed to play a role in acute graft-versus-host disease (aGVHD) after female-to-male stem cell transplantation (SCT). However, infiltrates of these T cells in aGVHD-affected tissues have not yet been reported. We evaluated the application of HLA-A2/HY dextramers for the in situ detection of HY-specific T cells in cryopreserved skin biopsy specimens. We applied the HLA-A2/HY dextramers on cryopreserved skin biopsy specimens from seven male HLA-A2+ pediatric patients who underwent stem cell transplantation with confirmed aGVHD involving the skin. The dextramers demonstrated the presence of HY-specific T cells. In skin biopsy specimens of three male recipients of female grafts, 68% to 78% of all skin-infiltrating CD8+ T cells were HY-specific, whereas these cells were absent in biopsy specimens collected from sex-matched patient–donor pairs. Although this study involved a small and heterogeneous patient group, our results strongly support the hypothesis that HY-specific T cells are actively involved in the pathophysiology of aGVHD after sex-mismatched stem cell transplantation.

CD3+/Tregs Ratio in Donor Grafts Is Linked to Acute Graft-versus-Host Disease and Immunologic Recovery After Allogeneic Peripheral Blood Stem Cell Transplantation - Corrected Proof

2011-11-07

Graft-versus-host disease (GVHD), mediated by mature T cells present in the donor graft, remains a major complication after allogeneic peripheral blood stem cell transplantation (PBSCT). Regulatory T cells (Tregs) (CD4+CD25highFoxp3+) are believed to maintain tolerance and to inhibit GVHD after allogeneic PBSCT (allo-PBSCT). In this study, we analyzed the graft CD3+/Tregs ratio (gCD3/Tregs R) and evaluated its impact on acute GVHD (aGVHD) and immunologic recovery after myeloablative allo-PBSCT. We analyzed 65 consecutive patients who underwent transplantation with unmanipulated peripheral blood stem cells from an HLA-identical related donor (n = 45) or an HLA-identical unrelated donor (n = 20). The median CD3+ and Tregs doses administered were 256 × 106/kg of body weight (range, 67-550 × 106/kg) and 12 × 106/kg (range, 2-21 × 106/kg), respectively; the median gCD3/Tregs R value was 18 (range, 8-250). Patients were subdivided into a high gCD3/Tregs R (≥36) group (HR; n = 26) and a low gCD3/Tregs R (<36) group (LR; n = 39). The incidence of aGVHD (grade II-IV) was lower in the LR group compared with the HR group (8/39 [20%] versus 22/26 [84%]; P < .001). Median cytomegalovirus-specific CD8+ T lymphocytes were significantly higher in the LR group than in the HR group at 1 month (2 cells/μL versus 0 cells/μL; P < .001), 2 months (6 cells/μL versus 1 cell/μL; P < .001), and 3 months (15 cells/μL versus 3 cells/μL; P < .001) months. Moreover, cytomegalovirus infection/disease was observed in 15% of patients in the LR group versus 69% of patients in the HR group (P < .001). At multivariate logistic regression, gCD3/Tregs R was correlated both with aGVHD (odds ratio, 2.50; 95% confidence interval, 1.30-4.50; P = .05) and with cytomegalovirus infection/disease (odds ratio, 2.35; 95% confidence interval, 0.9-5.00; P = .05). Taken together, our data may suggest that the balance in favor of graft Tregs content is able to mediate protective effects against aGVHD and to maintain an optimal microenviroment for the reconstitution of functional immunity.