Open AccessBovine herpesvirus 1 can cross the intact zona pellucida of bovine oocytes after artificial infection
Author(s) -
Vanessa Lopes Dias Queiroz-Castro,
Eduardo Paulino da Costa,
Sabrina do Carmo Alves,
Mariana MachadoNeves,
José Domingos Guimarães,
Lidiany Lopes Gomes,
Stella Vieira Domingos,
Caroline Gomides Ribeiro,
Rebeca Toledo Caldas,
Abelardo Silva-Júnior
Publication year - 2019
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0218963
Subject(s) - zona pellucida , bovine herpesvirus 1 , oocyte , andrology , biology , incubation , virus , herpesviridae , virology , embryo , immunology , viral disease , microbiology and biotechnology , medicine , biochemistry
Bovine herpesvirus 1 (BHV1) is an important bovine pathogen, responsible for respiratory diseases and reproductive problems. This study investigated the penetration capacity of BHV1 into oocytes after co-incubation for either 1 h or 24 h. Immunofluorescence assays in cumulus -oocyte complexes (COCs) and denuded oocytes (without the presence of cumulus cells) were performed and evaluated using confocal laser scanning microscopy. Blood samples and ovaries from BHV1 seronegative cows were used. The oocytes recovered were divided into two groups. Group I comprised COCs (n = 312) and denuded oocytes (n = 296), which were experimentally infected with BHV1 and incubated for 1 h at 38.5°C and 5% CO 2 . Group II comprised COCs (n = 425) and denuded oocytes (n = 405), which were co-incubated with BHV1 under the same conditions for 24 h. The negative control of these two groups was respectively subjected to the same protocol, except for exposure to BHV1. To our knowledge, this study provides the first evidence of BHV1 detection within COCs and denuded oocytes exhibiting intact zona pellucida when co-incubated with the virus for 24 h. Immunolocalization also confirmed the presence of BHV1 in the cytoplasm of the cumulus cells of all COCs exposed to the virus after both incubation periods. In conclusion, detection of BHV1 inside oocytes has a great meaning for the field of animal reproduction. The detection of BHV1 in different layers of cumulus cells also demonstrates that these cells are sources of viral infection.