Expansion of Cord Blood CD34+ Cells in Presence of zVADfmk and zLLYfmk Improved Their In Vitro Functionality and In Vivo Engraftment in NOD/SCID Mouse

摘要

BackgroundCord blood (CB) is a promising source for hematopoietic stem cell transplantations. The limitation of cell dose associated with this source has prompted the ex vivo expansion of hematopoietic stem and progenitor cells (HSPCs). However, the expansion procedure is known to exhaust the stem cell pool causing cellular defects that promote apoptosis and disrupt homing to the bone marrow. The role of apoptotic machinery in the regulation of stem cell compartment has been speculated in mouse hematopoietic and embryonic systems. We have consistently observed an increase in apoptosis in the cord blood derived CD34⁺ cells cultured with cytokines compared to their freshly isolated counterpart. The present study was undertaken to assess whether pharmacological inhibition of apoptosis could improve the outcome of expansion.