Risk of viral transmission via bone marrow progenitor cells versus umbilical cord blood hematopoietic stem cells in bone marrow transplantation

Hematopoietic stem cell transplantation (HSCT) is the treatment of choice for children and certain adults with malignant and nonmalignant hematologic disease. Since viral infections are the major problem, this study examined those that might potentially be transmitted to HSCT recipients via bone marrow (BM) versus umbilical cord blood (UCB). BM progenitor cells, peripheral blood leukocytes, and plasma samples were collected from 30 allogenic BM donors. Umbilical cord blood hematopoietic stem cells and plasma samples were also collected from 34 UCB donors. Viral DNA extracted and purified from collected specimens was processed using nested polymerase chain reactions (PCR) to detect human parvovirus B19 (HPV B19), human herpesvirus-6 (HHV-6), varicella-zoster virus (VZV), human cytomegalovirus (HCMV), and Epstein-Barr virus (EBV). The prevalences of HCMV DNA in collected BM progenitor cells versus UCB hematopoietic stem cells were 73% versus 23%, respectively. Conversely, HHV-6 DNA was not detected in any collected specimen by simple PCR. Distribution of the other investigated virus DNAs except EBV DNA was similar in specimens collected from both groups. EBV DNA was not determined in UCB hematopoietic stem cells. The results indicate that the risk of viral transmission to BM transplant recipients via UCB hematopoietic stem cells is less than that with BM progenitor cells.