输血传播病毒母婴垂直传播的途径与机制研究

Study on vertical transmission and its mechanism of transfusion transmitted virus

目的探讨输血传播病毒（transfusion transmitted virus，TTV）母婴垂直传播的途径和可能机制。方法采用地高辛标记探针，对36例产妇胎盘组织TTVDNA进行原位杂交定位检测。根据孕妇静脉血和胎儿脐血TTV DNA检测结果，将其胎盘组织标本分为以下三组：A组为两者均阳性12例；B组为孕妇阳性、胎儿阴性12例；C组为两者均阴性12例。结果TTV DNA阳性杂交信号呈蓝紫色团块状或颗粒状，位于感染细胞的细胞核内，偶见于细胞浆内。在36份胎盘组织标本中共有13份TTV DNA呈阳性，阳性率为36．1％。其中A组TTV DNA阳性8例（8／12），B组TTV DNA阳性5例（5／12），C组未检出TTV DNA。结论TTV可通过胎盘组织垂直传播进入胎儿血液，其传播机制属细胞源性母婴垂直传播。

Objective To investigate the maternal-fetal transmission and its mechanism of transfusion transmitted virus （TTV）. Methods Based on the results of TTV DNA in serum of pregnant women and umbilical venous blood of their newborns, the 36 placentae were divided into three groups. There were 12 cases in group A with positive TTV DNA for both mothers and their newborns and 12 cases in group B with positive TTV DNA only for mothers, and 12 cases in group C with negative TTV DNA in both mothers and their newborns. TTV DNA in placental tissues were detected by in situ hybridization with digoxin labeled probe. Results Positive TTV DNA was shown with blue-purple mass or particle in nuclei of infected cells. Among the 36 cases, TTV DNA was detected in 13 cases （36.1%）. There were 8 cases with positive TTV DNA in group A, 5 cases in group B, and none in group C. Conclusions TTV can transmit from mother to fetus via placenta from cell to cell.