IMMUNOSUPPRESSION IN MURINE MALARIA - SUPPRESSOR ROLE OF MACROPHAGES AND THEIR PRODUCTS DURING ACUTE AND CHRONIC PLASMODIUM-BERGHEI INFECTION

Marked suppression of IgM, IgG and IgA plaque forming cells was observed in mice immunized with sheep erythrocytes (T-dependent antigen) during acute Plasmodium berghei infection whereas during chronic infection mild immunosuppression was observed. When mice were immunized with polyvinylpyrrolidone (T-independent antigen), suppression in the number of plaque forming cells was observed at higher parasitaemias only during acute infection whereas during chronic infection the number remained within normal limits. Adoptive transfer studies suggested that the immunosuppression was mainly mediated by macrophages and their products. The suppressor role of macrophages and their products during acute malarial infection is highlighted.