Objective To explore  hepatitis C virus (HCV) persistent infection on biological characteristics, matrix metalloproteinase2 (MMP2) and MMP9 synthesis and secretion of cultured human placental syncytiotrophoblast(HPS).Methods The artificial reconstruction basement membrane Matrigel invasion assay, MTT  cell adhesion and cell motility experiments were used to study the change in invasion, invasionrelated adhesion and mobility of HPS(infected group) infected by serum of HCV RNA positive patients in vitro; concentrations of  human chorionic gonadotropin (HCG) cultured in supernatant was detected  to assess the impact of infection on cell  hormone synthesis and secretion. MMP2 and MMP9 levels in  cell culture supernatant were detected by enzyme linked immunosorbent assay(ELISA), the differences between  data of infected  and control group(serum culture of healthy persons)was compared, the results of ELISA was further validated by gelatin zymography, impact of infection on cell proMMP2 and proMMP9 mRNA expression was  analyzed by  RTPCR.Results The cell invasion, adhesion, motility as well as the ability of synthesis and secretion of hormone in infected group decreased  significantly  than those of  control group  (P<0.05). Secretion  of MMP2 and MMP9 in infected group decreased obviously compared with control group (MMP2: t=4.186,P<0.05; MMP9: t=2.325,P<0.05); RTPCR results showed that expression of  proMMP2 and proMMP9 mRNA in infected group was lower than  control group, but the difference was not significant(proMMP2: t=1.196, P>0.05; proMMP9: t=1.417, P>0.05). 
Conclusion The capacity  of HCV persistent infected HPS to synthesize and secrete MMP2 and MMP9 reduced. Persistent infection with HCV can inhibit  a variety of biological functions, including invasiveness and hormone synthesis and secretion of HPS cultured in vitro.

［Key words］hepatitis C virus；placenta； syncytiotrophoblast; molecular biology; MMP2;MMP9; in vitro test

［Chin Infect Control，2010，9（2）：76-80］