The collection of sufficient autologous hematopoietic progenitor cells (HPCs) for bone marrow grafts does not always guarantee a successful engraftment. A recent study in TRANSFUSION examined the role of CD8+ T cells in HPC mobilization and engraftment in 192 autologous HPC donors.
Researchers compared HPC cell mobilization in high and low HPC donors. They found that donors with the lowest collection of HPCs had the most CD8+ T cells (p=0.01), but CD8+ T cells inhibited HPC mobilization in vitro independent of the stromal cell-derived factor (SDF-1α) concentration. In addition, researchers observed a non-significant trend of faster neutrophil engraftment in donors with higher CD8:CD34 cell ratios. Results suggest that autologous CD8+ T cells inhibit HPC mobilization, but may help hone HPCs into the bone marrow and enhance engraftment.
Reference
