OBJECTIVEThis study was designed to investigate the effect of human cytomegalovirus (HCMV) on the proliferation of colony forming unit granulocyte-macrophage (CFU-GM), CFU-erythroid (CFU-E), burst forming unit-erythroid (BFU-E), CFU-multipotential (CFU-Mix) and CFU-megakaryocytic (CFU-Mk) progenitor cells of cord blood in vitro as well as the possible mechanism.

METHODSTwenty cord blood specimens were collected from the umbilical vein of normal full-term neonates delivered spontaneously. This study consisted of five groups: 3 Infection groups in which 0.1 mL 10(3), 10(4) and 10(5) plague forming unit (PFU) HCMV-AD169 virus solution was added to the culture system, an Inactivated control group in which the equal volume of inactivated virus solution was added, and a Blank control group (normal progenitor cells culture system without HCMV virus infection). Colony forming unit-assay was applied to detect the effects of HCMV-AD169 strain on the colony formation, inhibition rate and colony-maintaining duration of CFU- GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk of cord blood. PCR technique was used to demonstrate the existence of HCMV-DNA in the colony cells of cultured CFU-GM, CFU-E, CFU-Mix and CFU-Mk.

RESULTSHCMV-AD169 (10(3)PFU) in low concentration had inhibition effects on colony formation of the CFU-Mix and CFU-Mk (P < 0.05), whereas 10(5) PFU and 10(4) PFU HCMV-AD169 lead to decreased colonies in CFU-GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk compared with the Blank control and the Inactivated control groups (P < 0.05). The suppression effect of HCMV on the colony formation was dose-dependent. The colony-maintaining duration of the CFU-GM, CFU-E, BFU-E, CFU-Mix and CFU-Mk in the 10(5) PFU and 10(4) PFU HCMV infection groups was significantly shorter than that in the two control groups (P < 0.01). The low concentration of HCMV-AD169 (10(3)PFU) infection resulted in a shortened colony-maintaining duration of the CFU-Mix and CFU-Mk (P < 0.01), but had no effects on the colony-maintaining duration of CFU-GM, CFU-E and BFU-E. PCR amplification demonstrated the existence of HCMV-AD169 DNA in the colony cells of the three Infection groups.

CONCLUSIONSHCMV-AD169 strain can infect hematopoietic progenitors of cord blood and inhibit the proliferation of hematopoietic progenitors, associated with anemia, neutropenia and thrombocytopenia in HCMV patients.