RESUMO
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
One of the major problems in the development of successful recombinant vaccines against human immunodeficiency virus (HIV) is that of correct identification of a safe and effective vaccine delivery system with which to induce protective immunity using soluble protein antigens. An original method for constructing artificial immunogens in the form of spherical particles with yeast dsRNA in the center and hybrid proteins exposing epitopes of an infectious agent on the surface is reported. The dsRNA and the proteins were linked with spermidine-polyglucin-glutathione conjugates. Particles exposing HIV-1 epitopes were constructed, and their immunogenicity tested.
