In vitro interaction of bovine herpesvirus 1 with uterine tube epithelial cells and oocytes

Abstract

The aims of this study were to assess in vitro if bovine oocytes and oviductal epithelial cells from slaughterhouses for in vitro fertilization use may be infected with bovine herpesvirus 1; to analyze whether the treatment with trypsin according to the International Embryo Transfer Society guideline is efficient to inactivate the bovine herpesvirus 1; to morphologically study the virus-oocyte interaction through optical microscopy. In this study, Madin Darby Bovine Kidney (MDBK) cells that were co-cultured with oocytes matured in vitro and exposed to bovine herpesvirus 1 showed a cytopathic effect. The nested polymerase chain reaction for the supernatant was positive for the bovine herpesvirus 1, thus suggesting that the cytopathic effect observed in the MDBK monolayer was seen due to virus replication and not because of any culture toxicity. It was also observed cytopathic effect and positive nested polymerase chain reaction in MDBK cells co-cultured with in vitro maturated oocytes free of virus, but that were co-cultured in uterine epithelial cells pre-infected with bovine herpesvirus 1 and washed or not with trypsin, demonstrating an oocyte contamination by the virus. When trypsin-washing efficacy was evaluated, we could observe that the trypsin treatment was not able to eliminate the bovine herpesvirus 1 of the oocytes, and it was not observed any morphological difference in the infected oocytes.

Impairment on nuclear maturation rate in oocytes from cows naturally infected by bovine herpesvirus 1 (BoHV-1)

“…This agrees with observations by D' Angelo (1998), who found that both bovine oocytes matured in vitro with BoHV-1 and those matured in the absence of the virus had indistinguishable morphology. This finding was also verified by Gonçalves et al (2015), who also did not observe any morphological alterations in infected oocytes.…”