Reevaluation of the effect of levamisole in chronic brucellosis: in vitro and in vivo effect on monocyte phagocytosis

Abstract

The in vitro effect of levamisole on peripheral blood monocyte (P.B.M.) phagocytosis was studied in 32 patients with chronic brucellosis and 20 normal subjects. It was shown that levamisole enhances P.B.M. phagocytic capacity, not reaching however normal levels. A subgroup of 11 patients were treated with levamisole for 6 months and the drug effect on cellular and humoral immunity and monocyte phagocytosis was also studied. By the end of the 6 month treatment-study period, the following results were obtained: 1. six patients were symptom free while five had significantly improved. 2. T lymphocyte number and monocyte phagocytosis reached normal values. 3. Significant specific cellular immunity against both brucella antigens was noted. 4. B. lymphocytes showed no significant changes. 5. Antiglobulin titers varied. These findings suggest that the good therapeutical effect of levamisole in patients with chronic brucellosis could probably be a attributed to the enhancement of both T-cell function and monocyte phagocytosis.