Exposure to Leishmania major modulates the proportion of CD4+ T cells without affecting cellular immune responses.

The immune responses of individuals exposed to Leishmania major were evaluated and compared with those of non-exposed volunteers. Forty-one patients with active lesion(s), 43 healed individuals, 15 vaccinees 1 month or 1 year post vaccination, and 15 non-exposed volunteers were studied. Leishmanin skin test (LST) response, proliferative response of lymphocyte (PRL) to L.

The role of BCG in human immune responses induced by multiple injections of autoclaved Leishmania major as a candidate vaccine against leishmaniasis.

To determine if BCG was required in booster injections for autoclaved Leishmania major (ALM) vaccine, 75 volunteers with no response to leishmanin were injected double-blind and randomly with either ALM+BCG or BCG alone for the first injection and boosted either with ALM+BCG, ALM or BCG alone for the second and third. Addition of BCG to the boosters significantly increased the frequency and the magnitude of leishmanin skin tests (LSTs); however, there was no difference in proliferative and IFN-gamma responses (a month and a year later). Three injections of BCG produced no observable adverse reaction; hence BCG could be used in booster injections to increase the protective potential of this candidate vaccine.