PrPSc accumulation in placentas of ewes exposed to natural scrapie:: influence of foetal PrP genotype and effect on ewe-to-lamb transmission
PrPSc accumulation in placentas of ewes exposed to natural scrapie:: influence of foetal PrP genotype and effect on ewe-to-lamb transmission
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DOI：
10.1099/0022-1317-83-10-2607
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发表时间：
2002-10-01
影响因子：
3.8
通讯作者：
Schelcher, F
中科院分区：
文献类型：
--
作者：
Andréoletti, O;Lacroux, C;Schelcher, F
羊瘙痒病感染的母羊胎盘是已知的传染性。然而，胎盘在这些母羊的感染性是不系统的。高度怀疑母婴传播给羔羊，但尚未证实宫内胎儿受到污染。使用来自自然感染羊瘙痒症的羊群的母羊，证明了异常朊蛋白（PrPSc）在胎盘中的积累（i）由胎儿PrP基因密码子136、154和171处的多态性控制，（ii）主要限于胎盘组胎儿滋养层细胞。为了深入了解胎盘在羊瘙痒病传播中的作用，在从授精后140天至4个月龄的PrPSc阳性胎盘VRQ/VRQ母羊或PrPSc阴性胎盘ARR/VRQ母羊中取样的易感羔羊（基因型VRQ/VRQ）中建立了PrPSc传播模式。在VRQ/VRQ羔羊组，PrPSc的空间和时间积累模式是相似的，这表明出生后，而不是在子宫内的污染。
Placentas from scrapie-affected ewes are known to be infectious. Nevertheless, placenta infectivity in such ewes is not systematic. Maternal transmission to lambs is highly suspected but contamination of the foetus in utero has not been demonstrated. Using ewes from a naturally scrapie-infected flock, it was demonstrated that abnormal prion protein (PrPSc) accumulation in the placenta (i) is controlled by polymorphisms at codons 136, 154 and 171 of the foetal PrP gene and (ii) is restricted mainly to placentome foetal trophoblastic cells. In order to go deeper into the role of the placenta in scrapie transmission, the pattern of PrPSc dissemination was established in susceptible lambs (genotype VRQ/VRQ) sampled from 140 days post-insemination to the age of 4 months from either VRQ/VRQ ewes with PrPSc-positive placentas or ARR/VRQ ewes with PrPSc-negative placentas. In both VRQ/VRQ lamb groups, PrPSc spatial and temporal accumulation patterns were similar, suggesting post-natal rather than in utero contamination.