Burton G J, O'Shea S, Rostron T, Mullen J E, Aiyer S, Skepper J N, Smith R, Banatvala J E
Department of Anatomy, University of Cambridge, UK.
J Med Virol. 1996 Nov;50(3):237-43. doi: 10.1002/(SICI)1096-9071(199611)50:3<237::AID-JMV5>3.0.CO;2-A.
The significance of physical breaches of the trophoblastic layer of the placenta in transmission of HIV from mother to infant was evaluated in 17 HIV-infected pregnant women. Samples of peripheral blood were obtained from the women during pregnancy and at delivery, at which time a small piece of placental tissue was obtained from a random site and immediately placed into fixative. Blood samples were obtained from infants at or shortly after birth and thereafter at approximately 3-month intervals, until the age of 18 months, in order to determine their HIV infection status. HIV RNA and p24 antigen were quantified in maternal plasma and CD4 cells enumerated. Paediatric diagnosis was conducted using polymerase chain reaction, virus isolation, detection of p24 antigen, and measurement of class-specific antibodies. Placental damage was quantified and evaluated using transmission electron microscopy. Maternal viral load was low, with a mean RNA copy number of 8,237 per millilitre of plasma (range 230-37,233 copies/ml). Only two women were p24-antigenaemic, and CD4 numbers ranged from 0.09 to 2.8 x 10(9)/l. There was evidence of breaks in the trophoblastic surface to the depth of the basement membrane in all 17 placentas, and perivillous fibrinoid deposits were also observed to a varying degree in all samples. However, none of the 13 infants available for follow-up had evidence of infection with HIV. Superficial damage to the trophoblastic surface of the placenta, with exposure of the basement membrane and potential exposure of CD4-expressing cells, does not appear to be a significant factor in the transmission of HIV from mother to infant during pregnancy.
在17名感染HIV的孕妇中评估了胎盘滋养层物理破损在母婴传播HIV中的意义。在孕期及分娩时采集这些女性的外周血样本，同时从随机部位取一小片胎盘组织并立即放入固定剂中。在婴儿出生时或出生后不久采集血样，此后每隔约3个月采集一次，直至18个月龄，以确定其HIV感染状况。对母体血浆中的HIV RNA和p24抗原进行定量，并对CD4细胞进行计数。采用聚合酶链反应、病毒分离、p24抗原检测及特异性抗体检测进行儿科诊断。使用透射电子显微镜对胎盘损伤进行定量和评估。母体病毒载量较低，血浆中RNA平均拷贝数为每毫升8237个（范围为230 - 37233拷贝/毫升）。只有两名女性p24抗原血症阳性，CD4细胞数范围为0.09至2.8×10⁹/升。在所有17个胎盘中均有证据表明滋养层表面破损至基底膜深度，并且在所有样本中均不同程度地观察到绒毛周围纤维蛋白样沉积物。然而，13名可供随访的婴儿均无HIV感染证据。胎盘滋养层表面的浅表损伤，伴有基底膜暴露及表达CD4细胞的潜在暴露，在孕期母婴传播HIV过程中似乎并非重要因素。
