Early embryonic cells from in vivo-produced goat embryos transmit the caprine arthritis-encephalitis virus (CAEV).
The aim of this study was to investigate whether cells of early goat embryos isolated from in vivo-fertilized goats interact with the caprine arthritis-encephalitis virus (CAEV) in vitro and whether the embryonic zona pellucida (ZP) protects early embryo cells from CAEV infection. ZP-free and ZP-intact 8-16 cell embryos were inoculated for 2 h with CAEVat the 10(4) tissue culture infectious dose 50 (TCID50)/ml. Infected embryos were incubated for 72 h over feeder monolayer containing caprine oviduct epithelial cells (COECs) and CAEV indicator goat synovial membrane (GSM) cells. Noninoculated ZP-free and ZP-intact embryos were submitted to similar treatments and used as controls. Six days postinoculation, infectious virus assay of the wash fluids of inoculated early goat embryos showed typical CAEV-induced cytopathic effects (CPE) on indicator GSM monolayers, with fluids of the first two washes only. The mixed cell monolayer (COEC + GSM) used as feeder cells for CAEV inoculated ZP-free embryos showed CPE. In contrast, none of the feeder monolayers, used for culture of CAEV inoculated ZP-intact embryos or the noninoculated controls, developed any CPE. CAEV exposure apparently did not interfere with development of ZP-free embryos in vitro during the 72 h study period when compared with untreated controls (34.6 and 36% blastocysts, respectively, P > 0.05). From these results one can conclude that the transmission of infectious molecularly cloned CAEV-pBSCA (plasmid binding site CAEV) by embryonic cells from in vivo-produced embryos at the 8-16 cell stages is possible with ZP-free embryos. The absence of interactions between ZP-intact embryos and CAEV in vitro suggests that the ZP is an efficient protective embryo barrier.
Lamara
A
A
Laboratoire d'Etude des Risques Sanitaires liés aux Biotechnologies de la Reproduction, Ecole Nationale Vétérinaire de Nantes, France. lamara@vet-nantes.fr
Fieni
F
F
Mselli-Lakhal
L
L
Chatagnon
G
G
Bruyas
J F
JF
Tainturier
D
D
Battut
I
I
Fornazero
C
C
Chebloune
Y
Y
D000818:Animals; D016088:Arthritis-Encephalitis Virus, Caprine / Q000235:genetics / Q000502:physiology*; D003001:Cloning, Molecular; D046508:Culture Techniques; D003588:Cytopathogenic Effect, Viral; D004622:Embryo, Mammalian / Q000821:virology*; D004973:Estrus Synchronization; D006041:Goats / Q000196:embryology* / Q000821:virology*; D016180:Lentivirus Infections / Q000635:transmission*; D013480:Superovulation; D015044:Zona Pellucida / Q000502:physiology