RESUMO
We have previously described designing of polyepitope immunogens TBI and TCI, to stimulate the humoral and cellular immune responses to HIV-1. Here, immunogens TBI and TCI were used to create new vaccine construct named CombiHIVvac (Combined HIV-1 vaccine). CombiHIVvac is a virus-like particles (VLP) containing the DNA vaccine pcDNA-TCI as a core encapsulated within a spermidine-polyglucin-TBI conjugate. The immunogenic and toxic properties of the candidate vaccine CombiHIVvac have been studied. CombiHIVvac induces a strong humoral and CTL responses in mice; the antibodies are highly specific and are able to neutralize HIV-1 in vitro. Preclinical study demonstrated that CombiHIVvac does not cause long-term changes in physiological, biochemical and morphological parameters in immunized animals and thus can be recommended for clinical trials.
Assuntos
Vacinas contra a AIDS/imunologia , Epitopos/imunologia , HIV-1/imunologia , Vacinas de DNA/imunologia , Vacinas Virossomais/imunologia , Vacinas contra a AIDS/efeitos adversos , Vacinas contra a AIDS/química , Animais , Western Blotting , Células Cultivadas , Citocinas/biossíntese , Ensaio de Imunoadsorção Enzimática , Epitopos/genética , Anticorpos Anti-HIV/sangue , Humanos , Linfócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Testes de Neutralização , Vacinas de DNA/efeitos adversos , Vacinas de DNA/química , Vacinas Virossomais/efeitos adversos , Vacinas Virossomais/químicaRESUMO
A synthetic T cell immunogen (TCI) has been designed as a candidate DNA-based vaccine against Human immunodeficiency virus (HIV)-1 using cytotoxic T lymphocytes (CD8(+) CTL) and T-helper lymphocytes (CD4(+) Th) epitopes retrieved from the Los Alamos HIV Molecular Immunology Database. The protein 392 amino acids in length contains about eighty CTL-epitopes, many of which are overlapping and are totally restricted by ten different HLA class I molecules. To be able to detect CTL responses induced by a DNA vaccine in experimental animals, additional epitopes, restricted by mouse and Macaque rhesus major histocompatibility complex (MHC) class I molecules, were included in the target immunogen. The gene encoding the TCI protein was assembled, cloned into vector plasmids and expressed in a prokaryotic and a eukaryotic system. The presence of HIV-1 protein fragments in the immunogen structure was ascertained by ELISA and immunoblotting using panels of HIV-1-positive sera and monoclonal antibodies to p24. It has been demonstrated that DNA vaccine can induce both specific T cell responses (CTL and blast transformation) and specific antibodies in mice immunized with pcDNA-TCI.
Assuntos
Vacinas contra a AIDS/genética , Vacinas contra a AIDS/imunologia , Epitopos/genética , Epitopos/imunologia , Antígenos HIV/genética , Antígenos HIV/imunologia , HIV-1/genética , HIV-1/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Especificidade de Anticorpos , Sequência de Bases , Divisão Celular , DNA Viral/genética , DNA Viral/imunologia , Desenho de Fármacos , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Engenharia Genética , Anticorpos Anti-HIV/análise , Anticorpos Anti-HIV/biossíntese , Humanos , Imunoquímica , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Plasmídeos/imunologia , Vacinas de DNA/imunologiaRESUMO
Two systems have been examined for delivery of DNA-vaccine encoding a HIV-1 polyepitope CTL-immunogen (TCI). One is intended for i.m. injection and is in the form of an artificial virus like particle containing eukaryotic expression plasmid pcDNA-TCI encapsulated within a spermidine-polyglucin conjugate. The other is intended for mucosal immunization and is based on attenuated Salmonella typhimurium strain 7207, which can deliver pcDNA-TCI directly into professional antigen-presenting cells (APC). After immunization, the artificial VLP and recombinant Salmonella induced an enhanced HIV specific serum antibody, proliferative and CTL responses compared to those induced by naked pcDNA-TCI. The most significant responses were produced when pcDNA-TCI was delivered by Salmonella.
