目的：探讨人类巨细胞病毒(HCMV)感染对脐血造血祖细胞(CFU-GM、CFU-E、BFU-E、CFU-Mix及CFU-Mk)体外增殖的抑制作用及其机制。方法：20例脐血标本收集于正常足月顺产新生儿。实验共分5组:(1)3个HCMV感染组,每个感染组分别加入0.1 mL的103、104及105空斑形成单位(PFU)HCMV-AD169病毒液于培养体系中;(2)灭活对照组,加入同体积灭活HCMV病毒液;(3)空白对照组,不加HCMV病毒液,代之以同体积的IMDM。采用造血祖细胞体外半固体培养技术,培养、观察、计数HCMV-AD169株对脐血CFU-GM、CFU-E、BFU-E、CFU-Mix及CFU-Mk集落数、抑制率和集落维持时间;并用聚合酶链反应(PCR)技术检测集落细胞内HCMV-DNA。结果：(1)在造血祖细胞培养体系中加入不同滴度的HCMV-AD169后,104和105PFU滴度感染对CFU-GM、CFU-E、BFU-E、CFU-Mix及CFU-Mk集落形成均有显著的抑制作用,103PFU滴度感染对CFU-Mix及CFU-Mk集落形成有显著的抑制作用,与空白对照组和灭活对照组比较,差异有显著性(P<0.05)。病毒滴度越高,抑制程度越明显(P<0.05)。(2)104和105PFU滴度感染组CFU-GM、CFU-E、BFU-E、CFU-Mix及CFU-Mk集落维持时间较对照组明显缩短(P<0.01),103PFU滴度感染组CFU-Mix和CFU-Mk集落维持时间较对照组明显缩短(P<0.01)。(3)PCR显示3个感染组的CFU-GM、CFU-E、CFU-Mix及CFU-Mk集落细胞内均有HCMV-AD169DNA存在。结论：HCMV-AD169能直接感染CFU-GM、CFU-E、BFU-E、CFU-Mix及CFU-Mk造血祖细胞,并抑制造血祖细胞的增殖,这可能与HCMV感染患儿出现粒细胞减少、血小板减少和贫血等造血功能紊乱有关。

OBJECTIVE: This 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. METHODS: Twenty 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-AD_(169) 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-AD_(169) 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. RESULTS: HCMV-AD_(169)(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-AD_(169) 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-dependant.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-AD_(169)(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-AD_(169) DNA in the colony cells of the three Infection groups. CONCLUSIONS: HCMV-AD_(169) strain can infect hematopoietic progenitors of cord blood and inhibit the proliferation of hematopoietic progenitors,associated with anemia,neutropenia and thrombocytopenia in HCMV patients.