RESUMO
Two chimeric synthetic peptides incorporating immunodominant sequences from HTLV-I virus were synthesized. Monomeric peptides P7 and P8 represent sequences from transmembrane protein (gp21) and envelope protein (gp46) of the virus. The peptide P7 is a gp21 (374-400) sequence and the peptide P8 is a gp46 (190-207) sequence. Those peptides were arranged in a way that permits one to obtain different combinations of chimeric peptides (P7-GG-P8 and P8-GG-P7), separated by two glycine residues as spacer arms. The antigenic activity of these peptides were evaluated by UltramicroEnzyme-linked immunosorbent assay (UMELISA) by using panels of anti-HTLV-I-positive sera (n = 22), anti-HTLV-I/II-positive sera (n = 2), HTLV-positive (untypeable) serum samples (n = 2), and anti-HTLV-II-positive sera (n = 11), while specificity was evaluated with anti-HIV-positive samples (n = 19) and samples from healthy blood donors (n = 30). The efficacy of the chimeric peptides in solid-phase immunoassays was compared with the monomeric peptides and monomeric peptides together. The chimeric peptide P7-GG-P8 proved to be the most reactive with anti-HTLV-I-positive sera. These results may be related to a higher peptide adsorption capacity to the solid surface and for epitope accessibility to the antibodies. This chimeric peptide would be very useful for HTLV-I diagnostics.
Assuntos
Produtos do Gene env/imunologia , Antígenos HTLV-I/química , Proteínas Oncogênicas de Retroviridae/imunologia , Sequência de Aminoácidos , Ensaio de Imunoadsorção Enzimática , Produtos do Gene env/química , Produtos do Gene env/genética , Anticorpos Anti-HTLV-I/sangue , Antígenos HTLV-I/genética , Infecções por HTLV-I/diagnóstico , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Humanos , Epitopos Imunodominantes/química , Epitopos Imunodominantes/genética , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Oncogênicas de Retroviridae/química , Proteínas Oncogênicas de Retroviridae/genética , Produtos do Gene env do Vírus da Imunodeficiência HumanaRESUMO
Two chimeric synthetic peptides incorporating immunodominant sequences from HTLV-II virus were synthesized. Monomeric peptides P2 and P3 represent sequences from transmembrane protein (gp21) and envelope protein (gp46) of the virus. The peptide P2 is a gp21 (370-396) sequence and the peptide P3 is a gp46 (178-205) sequence. Those peptides were arranged in a way that permits one to obtain different combinations of chimeric peptides (P2-GG-P3 and P3-GG-P2), separated by two glycine residues as spacer arms. The antigenic activity of these peptides was evaluated by UltramicroEnzyme-linked immunosorbent assay (UMELISA) by using panels anti-HTLV-II-positive sera (n = 11), anti-HTLV-I/II-positive sera (n = 2), HTLV-positive (untypeable) serum samples (n = 2), and anti-HTLV-I-positive sera (n = 22), while specificity was evaluated with anti-HIV-positive samples (n = 19) and samples from healthy blood donors (n = 30). The efficacy of the chimeric peptides in solid-phase immunoassays was compared with the monomeric peptides and a mixture of the monomeric peptides. Higher sensitivity was observed for chimeric peptide Q5 assay. Those results may be related to a higher peptide adsorption capacity to the solid surface and for epitope accessibility to the antibodies. This chimeric peptide would be very useful for HTLV-II diagnostic.
Assuntos
Produtos do Gene env/imunologia , Anticorpos Anti-HTLV-II/sangue , Antígenos HTLV-II/química , Vírus Linfotrópico T Tipo 2 Humano/imunologia , Proteínas Oncogênicas de Retroviridae/imunologia , Sequência de Aminoácidos , Ensaio de Imunoadsorção Enzimática , Produtos do Gene env/química , Produtos do Gene env/genética , Antígenos HTLV-II/genética , Infecções por HTLV-II/diagnóstico , Infecções por HTLV-II/imunologia , Vírus Linfotrópico T Tipo 2 Humano/genética , Humanos , Epitopos Imunodominantes/química , Epitopos Imunodominantes/genética , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Oncogênicas de Retroviridae/química , Proteínas Oncogênicas de Retroviridae/genética , Produtos do Gene env do Vírus da Imunodeficiência HumanaRESUMO
The present study evaluated four chimeric synthetic peptides incorporating immunodominant sequences from HTLV-1 virus. Monomeric peptides M1, M2, and M3 represent sequences from core (p19) and envelope (gp46) of the virus. The peptide M1 is a p19 (105-124) sequence, the peptide M2 is a gp46 (190-207) sequence, and the peptide M3 is a gp 46 sequence with substitution of proline at position 192 by serine. Those peptides were arranged in such a way that permits one to obtain different combinations of chimeric peptides (M1-M2, M2-M1, M1-M3, and M3-M1). Two glycine residues were used as arm spacers for separating the two sequences. The antigenicity of these peptides was evaluated in an ultramicroenzyme-linked immunosorbent assay (UMELISA) using sera of human T cell leukemia virus type I (HTLV-I)-infected individuals (n = 24), while specificity was evaluated with anti-HTLV-II-positive samples (n = 11) and healthy blood donors (n = 25). The results were compared to plates coated with monomeric peptides M1, M2, and M3. The chimeric peptide orientation (M1-M2) and the proline at position 192 of the gp46 peptide showed higher sensitivity.
