Is PGL-1 also present in Leishmania donovani promastigotes?

ABSTRACT

A soluble antigen complex (SAC) derived from the ruptured promastigotes of Leishmania donovani parasites (LD-SAC) was used for complement fixation test (CFT) in leprosy Cases of tuberculoid and borderline tuberculoid leprosy, post-kala azar dermal leishmaniasis (TT, BT, PKDL) and control sera gave negative CFT. Smear-positive cases of borderline (BB, BL) and lepromatous (LL) leprosy and drug-resisting cases of pulmonary tuberculosis gave positive CFT; smear-negative cases of LL leprosy sera also gave positive CFT. Sera of smear-negative inactive LL patients contained only PGL-1 and PDIM antigens for a long time after they become inactive. Therefore, the positive CFT in inactive LL makes us suspect whether PGL-1 is present in LD promastigotes.