Okino, Cintia Hiromi [UNESP]Alessi, Antônio Carlos [UNESP]Montassier, Maria de Fátima Silva [UNESP]Rosa, Artur Jordão de MagalhãesWang, XiuqingMontassier, Hélio José [UNESP]2014-05-272014-05-272013-08-01Viral Immunology, v. 26, n. 4, p. 259-267, 2013.0882-82451557-8976http://hdl.handle.net/11449/76150The antibody and cellular immune responses against infectious bronchitis virus (IBV) were evaluated at mucosal sites of chickens after immunization with various doses of an attenuated vaccine at 1 day of age. The correlation of these immune responses with protection of tracheal tissues was evaluated after experimental infection of these birds. Significantly reduced tracheal pathologic effects, measured according to ciliostasis and histology lesions, and reduced viral load were observed only in the full-dose vaccinated group at 5 days post-infection (dpi), while incomplete protection was observed for the subdose vaccinated groups. Moreover, birds of vaccinated groups, especially with full dose, developed higher levels of lachrymal IBV-specific IgG and IgA and increased the expression of cell-mediated immunity (CMI) genes, such as gamma interferon (IFNγ), CD8+ T cell marker, and granzyme homolog A more rapidly. In addition, these humoral and cellular immune responses evaluated at mucosal sites correlated significantly with tracheal protection against homologous IBV challenge in a vaccine dose-dependent manner. The results indicate that IgG, IgA and CD8+ T cell responses developed at mucosal sites after IBV vaccination of day-old chicks, could be taken as good correlates of protection against this virus. © 2013, Mary Ann Liebert, Inc.259-267enggamma interferongranzyme Aimmunoglobulin Aimmunoglobulin Glive vaccineanimal experimentanimal tissueantibody responseavian infectious bronchitisAvian infectious bronchitis virusCD8+ T lymphocytecellular immunitychickenciliary dyskinesiacontrolled studycorrelational studydose responseexperimental infectiongene expressionhistopathologyhumoral immunityinfection preventionlacrimal glandnonhumannucleotide sequencetracheavaccinationvirus loadArtigo10.1089/vim.2013.0015WOS:000323154500005Acesso restrito2-s2.0-84882363786