暴露于自然痒病的母羊胎盘组织中PrP(Sc)的蓄积：胎儿PrP基因型的影响及对母羊至羔羊传播的作用

PrP(Sc) accumulation in placentas of ewes exposed to natural scrapie: influence of foetal PrP genotype and effect on ewe-to-lamb transmission.

作者信息

Andréoletti Olivier, Lacroux Caroline, Chabert Armelle, Monnereau Laurent, Tabouret Guillaume, Lantier Frédéric, Berthon Patricia, Eychenne Francis, Lafond-Benestad Sylvie, Elsen Jean-Michel, Schelcher François

机构信息

UMR 959 INRA-ENVT, Physiopathologie Infectieuse et Parasitaire des Ruminants, Ecole Nationale Vétérinaire, 23 Chemin des Capelles, 31076 Toulouse Cedex 3, France1.

INRA, Laboratoire de Pathologie Infectieuse et Immunologie, Nouzilly, France2.

出版信息

J Gen Virol. 2002 Oct;83(Pt 10):2607-2616. doi: 10.1099/0022-1317-83-10-2607.

DOI:10.1099/0022-1317-83-10-2607

PMID:12237445

Abstract

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 (PrP(Sc)) 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 PrP(Sc) 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 PrP(Sc)-positive placentas or ARR/VRQ ewes with PrP(Sc)-negative placentas. In both VRQ/VRQ lamb groups, PrP(Sc) spatial and temporal accumulation patterns were similar, suggesting post-natal rather than in utero contamination.

摘要

已知感染羊瘙痒病的母羊的胎盘具有传染性。然而，此类母羊的胎盘感染并不具有普遍性。虽然高度怀疑存在母羊向羔羊的垂直传播，但尚未证实子宫内胎儿受到感染。利用来自自然感染羊瘙痒病的羊群的母羊，研究表明，胎盘中异常朊病毒蛋白（PrP(Sc)）的积累：（i）受胎儿PrP基因第136、154和171密码子多态性的控制；（ii）主要局限于胎盘小叶的胎儿滋养层细胞。为了更深入地了解胎盘在羊瘙痒病传播中的作用，对从授精后140天到4月龄的易感羔羊（VRQ/VRQ基因型）进行了研究，这些羔羊要么来自胎盘PrP(Sc)呈阳性的VRQ/VRQ母羊，要么来自胎盘PrP(Sc)呈阴性的ARR/VRQ母羊。在两个VRQ/VRQ羔羊组中，PrP(Sc)的时空积累模式相似，这表明感染发生在出生后而非子宫内。