Mechanisms of immunity to Leishmania major infection in mice: The contribution of DNA vaccines coding for two novel sets of histones (H2A–H2B or H3–H4)

The immune phenotype conferred by two different sets of histone genes (H2A–H2B or H3–H4) was assessed. BALB/c mice vaccinated with pcDNA3H2AH2B succumbed to progressive cutaneous leishmaniosis (CL), whereas vaccination with pcDNA3H3H4 resulted in partial resistance to Leishmania major challenge associated with the development of mixed T helper 1 (Th1)/Th2-type response and a reduction in parasite-specific Treg cells number at the site of infection. Therefore, the presence of histones H3 and H4 may be considered essential in the development of vaccine strategies against CL based on the Leishmania histones.