title: Protection of cynomolgus monkeys against infection by human T-cell leukemia virus type-I by immunization with viral env gene products produced in Escherichia coli.
abstract: Protection against human T-cell leukemia virus type-I (HTLV-I) infection in cynomolgus monkeys, achieved by immunizing the animals with env gene products of HTLV-I produced in Escherichia coli, was evaluated. Four monkeys that had been immunized with the env product produced antibody against HTLV-I gp68 and gp46, and their sera were found to cause strong inhibition of syncytium formation of a cat fibroblast cell line induced by HTLV-I. Immunized and non-immunized monkeys were challenged with live MT-2 cells, a high HTLV-I-producer cell line. After challenge, all the control non-immunized monkeys were infected with HTLV-I, as judged by the frequent detection of HTLV-I-antigens in cultures of their peripheral blood mononuclear cells (PBMC), whereas no antigens were recovered from PBMC of immunized monkeys. These results indicate that humoral immunity against HTLV-I-envelope protein elicited by immunization with the polypeptides synthesized in bacteria protected the monkeys against primary infection with HTLV-I.
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis; D017977:Deltaretrovirus / Q000276:immunology*; D015480:Deltaretrovirus Antibodies; D006800:Deltaretrovirus Infections / Q000276:immunology / Q000517:prevention & control*; D004926:Escherichia coli / Q000235:genetics; D007114:Immunization; D008252:Macaca fascicularis; D008297:Male; D014759:Viral Envelope Proteins / Q000276:immunology*; D014765:Viral Vaccines / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D015480:Deltaretrovirus Antibodies; D014759:Viral Envelope Proteins; D014765:Viral Vaccines