Dynamics and genetics of PrPSc placental accumulation in sheep.
Placentae from scrapie-affected ewes are an important source of contamination. This study confirmed that scrapie-incubating ewes bearing susceptible genotypes could produce both abnormal prion protein (PrPSc)-positive and -negative placentae, depending only on the PRP genotype of the fetus. The results also provided evidence indicating that scrapie-incubating ARR/VRQ ewes may be unable to accumulate prions in the placenta, whatever the genotype of their progeny. Multinucleated trophoblast cells appeared to play a key role in placental PrPSc accumulation. PrPSc accumulation began in syncytiotrophoblasts before disseminating to uninucleated trophoblasts. As these result from trophoblast/uterine epithelial cell fusion, syncytiotrophoblast cells expressed maternal and fetal PrPC, whilst uninucleated trophoblast cells only expressed fetal PrPC. In ARR/VRQ scrapie-infected ewes, expression of the ARR allele by syncytiotrophoblasts appeared to prevent initiation of PrPSc placental deposition. The absence of prions in affected ARR/VRQ sheep placentae reinforces strongly the interest in ARR selection for scrapie control.
Lacroux
C
C
UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France.
Corbière
F
F
UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France.
Tabouret
G
G
UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France.
Lugan
S
S
UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France.
Costes
P
P
UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France.
Mathey
J
J
UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France.
Delmas
J M
JM
UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France.
Weisbecker
J L
JL
INRA Domaine de Langlade, 31450 Pompertuzat, France.
Foucras
G
G
UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France.
Cassard
H
H
UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France.
Elsen
J M
JM
INRA Station d'Amélioration Génétique des Animaux, 31326 Castanet Tolosan, France.
Schelcher
F
F
UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France.
Andréoletti
O
O
UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France.
D000483:Alleles; D000818:Animals; D005260:Female; D005333:Fetus; D005838:Genotype; D007150:Immunohistochemistry; D010920:Placenta / Q000737:chemistry* / Q000473:pathology; D018620:PrPSc Proteins / Q000032:analysis*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D012608:Scrapie / Q000378:metabolism* / Q000473:pathology; D012756:Sheep; D014327:Trophoblasts / Q000737:chemistry
D018620:PrPSc Proteins