RESUMO
These studies defined SRV-2 envelope peptides 96-102, 127-152, and 233-249 as T cell epitopes that induce significant T cell proliferation. Peripheral blood lymphocytes of Celebes macaques (Macaca nigra) exposed to SRV-2 and currently virus- antibody+, cultured with SRV-2 virus show strongly suppressed T cell responses and have two immunoregulatory T cell populations.
Assuntos
Retrovirus dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Anticorpos Antivirais/sangue , Antígenos CD4 , Antígenos CD8 , Epitopos , Tolerância Imunológica , Técnicas In Vitro , Ativação Linfocitária , Macaca/imunologia , Fragmentos de Peptídeos/imunologia , Retrovirus dos Símios/isolamento & purificação , Síndrome de Imunodeficiência Adquirida dos Símios/microbiologia , Proteínas do Envelope Viral/imunologiaRESUMO
Various mouse strains were immunized with either SRV-1 or SRV-2 virus adsorbed on alum. Seven to 14 days later spleen cells were removed, and spleen cells were cultured with varying amounts of SRV-1 virus and SRV-2 virus, or varying amounts of selected SRV-1 and SRV-2 synthetic envelope peptides to determine their ability to initiate T cell proliferative responses. Our studies demonstrated that all mouse strains tested gave strong proliferative responses with SRV-2 virus. In contrast, SRV-1 virus induced T cell proliferative responses only in H-2k mouse strains. This apparent major histocompatibility complex (MHC)-restriction of SRV-1 virus-induced T cell proliferation correlates with the increased pathogenicity of SRV-1 virus in rhesus monkeys. The SRV envelope peptide 233-249 which is shared by both SRV-1 and SRV-2 virus initiates strong proliferative responses in both SRV-1 and SRV-2 virus immunized mice. The SRV-2 envelope peptide 96-102 initiates significant proliferative responses in SRV-2 immunized mice, and constitutes both a T and B cell epitope. The SRV-2 envelope peptide 127-152 has a 70% homology with the C-terminal region of SRV-1 peptide 142-167. The ability of SRV-2 peptide 127-152 to initiate T cell proliferation in SRV-1 virus immunized mice and the failure of the SRV-1 peptide 142-162 to initiate proliferation suggests that the region encompassing residues 160-167 must represent a T cell epitope in mice immunized with SRV-1 virus.
Assuntos
Produtos do Gene env/imunologia , Retrovirus dos Símios/imunologia , Linfócitos T/imunologia , Proteínas do Envelope Viral/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Linfócitos B/imunologia , Epitopos , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos , Dados de Sequência Molecular , Peptídeos/imunologiaRESUMO
Synthetic envelope peptides of a simian retrovirus (SRV-2) were used to define both T- and B-cell epitopes of the envelope protein. The SRV-2 peptide 100-106 specifically blocks rhesus anti-SRV-2 neutralizing antibody activity, and a peptide 100-106 keyhole limpet hemocyanin conjugate induces a strong antipeptide antibody response. SRV-2 peptide 100-106 and 233-249 induces good T-cell proliferation of murine spleen cells immunized with the SRV-2 virus. Thus, SRV-2 envelope peptide 100-106 represents both a T- and B-cell epitope, and peptide 233-249 a T-cell epitope.