Antigenicity of chimeric synthetic peptides based on HTLV-1 antigens and the impact of epitope orientation

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. Th e 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 pro line 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 e valuated 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 p lates coated with monomeric peptides MI, M2, and M3. The chimeric peptide o rientation (M1-M2) and the proline at position 192 of the gp46 peptide show ed higher sensitivity. (C) 2000 Academic Press.