Long-term protection of mice against Leishmania major with a synthetic peptide vaccine

A single synthetic T cell epitope (PT3), obtained from the histidine zinc-b inding region of the metalloprotease gp63, was employed in a vaccine trial using two virulent strains of L. major. When a single subcutaneous injectio n of PT3 was delivered with the Th1 stimulating adjuvant poloxamer 407, BAL B/c mice were protected for at least 10 months against the disease. Vaccina ted mice were largely free of lesions on termination of the experiment. Pro tection was similar for both L. major MRHP/SU/59 Neals and L. major WHOM/IR /-/173 strains which manifest different disease sequelae. Thus, these data provide evidence that a single subcutaneous injection of a single synthetic T cell epitope is sufficient to provide long-lasting protection against tw o highly virulent strains of L. major in BALB/c mice. (C) 1999 Elsevier Sci ence Ltd. All rights reserved.