Direct Growth Suppression of Myeloid Bone Marrow Progenitor Cells But Not Cord Blood Progenitors by Human Cytomegalovirus In Vitro

Recently, considerable interest has arisen as to use cord blood (CB) as a source of hematopoietic stem cells for alloge-nic transplantation when bone marrow (BM) from a familial HLA-matched donor is not available. Because human cyto-megalovirus (HCMV) has been shown to inhibit the prolifera-tion of BM progenitors in vitro, it was important t o examine whether similar effect could be observed in HCMV-infected CB cells. Therefore, the effect of HCMV challenge on the proliferation of myeloid progenitors from BM and CB was compared using both mononuclear cells (MNC) and purified CD34+ cells. A clinical isolate of HCMV inhibited the colony formation of myeloid BM progenitors responsive to granulo-cyte-macrophage colony-stimulating factor (CSF), granulo-cyte-CSF, macrophage-CSF, interleukin-3 (IL-3) and the com-bination of IL-3 and stem cell factor (SCF). In contrast, colon