Sera from 167 patients across the spectrum of leprosy and 46 endemic controls were screened for lymphocytotoxic acitivity (LCA). The Terasaki microdroplet lymphocytotoxicity assay was performed at 37°C and 15°C to test sera for LCA against a panel of lymphocytes from 50 donors which represented most known HLA-ABC antigens. Raised complement-dependent LCA at 15°C was seen in leprosy patients with histories of erythema nodosum leprosum (ENL) or reversal/Type I (I) reactions. Eighty-six per cent of lepromatous (LL) patients with a history of ENL (n = 21, P < 0.001), 83% of borderline lepromatous (BL) and 88% of borderline tuberculoid patients (BT) with a history of Type I reactions (n = 12, P < 0.01 and n = 24, P < 0.001 respectively) had LCA compared to 39% of endemic controls (n = 46). LCA was attributed to IgM on the basis of reduced activity when serum was treated with both dithiothreitol or absorbed with antiserum for IgM. Removal of immune complexes and rheumatoid factor did not influence LCA. LCA-positive sera reacted similarly with allogeneic lymphocytes from either healthy donors or leprosy patients. Moreover LCA-positive sera reacted with autologous lymphocytes. Specificities for HLA-ABC antigens were not identified. The potential role of these autoantibodies, manifested in leprosy patients with hypersensitivity reactions remains speculative.
|Number of pages||7|
|Journal||Clinical and Experimental Immunology|
|Publication status||Published - 1989|