Generation of Leishmania-specific short-term T-cell lines derived from peripheral blood of cured American cutaneous leishmaniasis patients.

The putative protective immune response in localized cutaneous leishmaniasis caused by Leishmania braziliensis braziliensis (Lbb) was analysed by generation of short term T-cell lines from peripheral blood lymphocytes (PBL) of three patients. All had had active skin lesions but were clinically cured at the time of study. PBL were stimulated in vitro with sonicated Lbb promastigotes; blasts were isolated after 5 days and propagated for 9 to 16 days before being tested for proliferative capacity. The majority of propagated cells were T4-positive and reacted with Leishmania antigens. An apparent cross-reactivity with Trypanosoma cruzi (T. cruzi) soluble antigen was recorded. Although preliminary, these data indicate that immune T cells derived from cured LCL patients can recognize antigens common to Lbb and T. cruzi.