The effects of chemotherapy on antibody levels in lepromatous patients

Abstract

We compare whole cell ELISA antigens (Mycobacterium leprae) and two specific antigens: PG-I, phenolic glycolipid I of M. leprae and M-BGG, a synthetic antigen representing the terminal sugar of PG-I for their effectiveness in detecting antibody during chemotherapy. By the end of the 1st year of treatment, antibody levels to M-BGG had declined by 42% of the initial ELISA values, by the end of the 2nd year by 61% and at the end of 3 years by 68%. Declines of similar magnitude were seen with the other antigens. We examined these sera by RID for changes in levels of IgG, IgM and IgA antibodies. The levels of IgG remained abnormally high throughout the 3 years of antimicrobial therapy. The serum levels of IgM and IgA antibodies remained at the upper limits of normal range. The decline seen with antibody to M. leprae antigens was not reflected by a similar decline of serum immunoglobulin levels. Thus, application of ELISA monitoring during the course of treatment may be valuable in measuring the effectiveness of chemotherapy.