Identification of epitopes within the circumsporozoite protein of Plasmodium vivax recognized by murine T lymphocytes

Abstract

The murine cellular immune response to the circumsporozoite (CS) protein of Plasmodium vivax was characterized using five synthetic peptides, some of which we identified as corresponding to T cell epitopes. The peptides P308–320, P344–355 and P353–364 were immunogenic, inducing a genetically restricted proliferative response, due to the activation of CD4 + T cells. The peptide P308–320 was recognized only by the lymphocytes of B10 (H-2 b) mice. The other two peptides were recognized by primed lymphocytes of H-2 a and H-2 k mice. Of interest was the finding that one of these peptides, P353–364, induced a proliferative response of a large percentage of immune outbred Swiss mice. Our data provide evidence that, at least in mice, there is recognition of multiple T cell epitopes within the major surface antigen of P. vivax sporozoites.