Evaluation of immunodominant epitopes of human T-lymphotropic virus type 1 (HTLV-I) using synthetic peptides.

Human T-lymphotropic virus type 1 (HTLV-I) causes adult T-cell leukemia/lymphoma (ATLL) and has been associated with a variety of immunologically-mediated diseases. Recently, the immunodominant epitopes of HTLV-I have begun to be defined through the utilization of synthetic peptides and recombinant proteins. Strategies to define the conformational features of immunogenic peptides and design chimeric and multivalent constructs that mimic native viral proteins have provided the opportunity to create an effective synthetic vaccine against HTLV-I infection. An ideal peptide vaccine to be universally immunogenic must incorporate rationally designed antigenic determinants that accurately mimic the corresponding structural architecture found in native proteins and elicit relevant components of the immune system. We have recently designed and tested chimeric and beta-sheet template constructs containing HTLV-I immunodominant peptide motifs that elicit neutralizing antibody responses and overcome genetically restricted immune responses. To further illustrate putative vaccine candidates, HTLV-I env and tax proteins were analyzed using various computer-predicted correlates of protein antigenicity, secondary structural predictions, and major histocompatibility complex class I binding motifs. These approaches provide the opportunity to design synthetic peptide vaccines against HTLV-I infection that are based on structurally defined criteria, as well as test the influence of glycosylation on peptide conformation and immunogenicity.