Studies on immune responses to larval cestodes in mice: a simple mechanism of non-specific immunosuppression in Mesocestoides corti-infected mice.

After intraperitoneal (i.p.) injection of sheep erythrocytes (SRBC) or dinitrophenylated Ficoll (DNP-Ficoll), mice infected with the larval cestode, Mesocestoides corti, contain at least 20x fewer antibody-secreting cells (PFC) in their spleens (or spleens plus lymph nodes) than uninfected mice. By contrast, intravenous injection of antigen leads to normal PFC responses. Results of studies on the fate of labelled syngeneic erythrocytes and foreign proteins suggest that i.p. injected materials are retained in the inflamed peritoneal cavity. Sequestration of antigen, and its subsequent local destruction, presumably accounts for the markedly suppressed systemic immune responses induced by i.p. injected antigens in M. corti-infected mice.