Effect of Ex Vivo Culture of CD34⁺ Bone Marrow Cells on Immune Reconstitution of XSCID Dogs Following Allogeneic Bone Marrow Transplantation

T cell reconstitution following DLA-matched or haploidentical bone marrow transplantation of XSCID dogs. Absolute number of peripheral CD45RA⁺ T cells in XSCID dogs following transplantation with ≥5 x 10⁶ CD34⁺ bone marrow cells from normal matched (n=10) or haploidentical (n=6) donors.

Longitudinal analysis of T cell reconstitution following bone marrow transplantation of XSCID dogs with cultured bone marrow CD34⁺ cells. Proportion of peripheral T cells (A), and proportion (B) and absolute number (C) of peripheral T cells expressing a naïve (CD45RA⁺) phenotype in XSCID dogs following transplantation with CD34⁺ bone marrow cells following culture for 18 hours or 4.5 days in comparison with 8 dogs transplanted with freshly isolated CD34⁺ cells in Fig1, which that were incorporated into our breeding program.

T cell function following bone marrow transplantation. Proliferative response of peripheral blood T cells following PHA stimulation in dogs R1789, X299, R1844, and R1847 at 4 months post BMT. The results of a normal dog analyzed at the same time are also presented. Percentages represent the proportion BrdU⁺ cells.

Thymus output following bone marrow transplantation. TREC levels in XSCID dogs following transplantation with freshly isolated CD34⁺ cells or CD34⁺ cells cultured for 18hours or 4.5 days (A). Histologic appearance of the thymus in XSCID dogs one year following transplantation with freshly isolated bone marrow CD34⁺ cells or CD34⁺ cells cultured for 18hours or 4.5 days (B).