LINEAR FUSION OF HIV-1 B-EPITOPES AND HETEROLOGOUS T-CELL EPITOPES .1. PRESERVATION OF THE ANTIGENIC PROPERTIES OF THE HIV-1 B-CELL EPITOPES

Peptides were synthesized combining an immunodominant B-cell epitope f rom gp41 of HIV-1 with heterogenous T-cell epitopes from tetanus toroi d or hepatitis B core antigen with no spacer bridge between the epitop es. The antigenic properties of the B-cell epitope within the composit es were evaluated. The majority of the rabbit sera against the immunod ominant B-cell epitope from gp41 recognized the B-cell epitope of gp41 and its composites as closely related structures. Comparative study o f the composite peptide recognition by HIV-1 antibody-positive human s era revealed that 82% of them similarly recognized a single gp41 epito pe and its composites. The differences in the affinity values for the B-cell epitope from gp41 and its composites was less prominent than th e difference between the affinity values for the single peptides deriv ed from the immunodominant region of gp41. This indicates that the B-c ell epitope from gp41 was not changed by fusion to heterologous amino acid sequences. The evaluation of the immunogenicity of the composites would reveal whether the antigenic characteristics can be of use in t he selection of the components of multivalent peptide vaccines.