Defective concanavalin A-induced suppression in bancroftian filariasis.

A concanavalin-A-induced suppressor cell assay was carried out in 10 patients with chronic filarial disease, 13 asymptomatic microfilaria carriers and 7 healthy subjects. Both the chronic filarial patients and the asymptomatic microfilaria carriers showed statistically significant reduced suppression indices when compared with the control subjects. The reduction in suppression indices was greater in the microfilaria carriers than in the chronic filarial patients.