Cellular immunity in chronic Chagas' disease

Abstract

The cellular immune response was assessed in 20 patients with chronic Chagas'' disease (American trypanosomiasis). Thymus-derived [T] lymphocyte function was determined in vivo by cutaneous reactivity to several antigens including a soluble preparation derived from Trypanosoma cruzi and sensitization to 2,4-dinitrochlorobenzene. The in vitro T-cell reactivity was investigated by the proliferative response to phytohemagglutinin and to T. cruzi antigen and by inhibition of leukocyte migration with the specific antigen. In addition, the proportion and absolute numbers of peripheral blood T- and B[bone-marrow-derived]-lymphocytes were determined by rosette formation. The general and specific cellular immune response, evaluated by the tests herein mentioned, is apparently well preserved in patients with Chagas'' disease. Chronic Chagas'' disease apparently is not associated with cellular immune deficiency, and does not lead to it. Conceivably, the active participation of delayed hypersensitivity may play an important role in the expression of the human chagasic lesions.