IMMUNOMODULATION BY LEVAMISOLE IN PATIENTS WITH RECURRENT APHTHOUS ULCERS OR ORAL LICHEN-PLANUS

The purpose of this study was to evaluate the effect of levamisole on the immune system of patients with recurrent aphthous ulcers (RAU) or oral lichen planus (OLP) in an open trial. Lymphocyte subsets, serum i mmunoglobulins, and circulating immune complexes (CIC) in patients wit h RAU or OLP and in normal control subjects were determined by an indi rect immunofluorescence (IIF) technique with monoclonal anti-lymphocyt e antibodies, by single radial immunodiffusion, and by precipitation w ith 3% polyethylene glycol, respectively. m addition, the anti-nuclear antibodies (ANA) and anti-basal cell antibodies (anti-BCA) in sera we re detected by an IIF technique. We found a significant improvement in clinical symptoms and normalization of the decreased CD4/CD8 ratio in RAU patients after levamisole treatment. Moreover, the decreased CD4/ CD8 ratio, which persisted until the remission stage in the untreated RAU patients, reverted to normal in the active late stage in the levam isole-treated patients. This reversion of aberrant cellular immunity i n an earlier stage of the ulcer cycle may explain why RAU patients exp erience symptom improvement after levamisole treatment. Although RAU p atients treated with levamisole for 1 to 3 or 4 months still had highe r than normal levels of CIC and serum immunoglobulins, the levels of t heir IgA and IgM returned to normal values after 4 months of levamisol e treatment. The serum ANA detected in 6 patients with RAU and 3 patie nts with erosive OLP disappeared after 1-22 months of levamisole treat ment. The disappearance of serum anti-BCA was also observed in 50% of the anti-BCA-positive patients with erosive OLP after 3-13 months of l evamisole treatment. These findings suggest that levamisole has modula ting effects on both cell-mediated and humoral immunity in patients wi th RAU or OLP.