Anti-idiotypic T cells in human schistosomiasis

We have developed an in vitro model of granuloma formation for the purpose of studying the immunological components of granulomatous hypersensitivity in patients infected with S. mansoni. Our previous studies have shown that 1) granulomatous hypersensitivity can be studied by examining the cellular reactivity manifested as multiple cell layers surrounding antigen-conjugated polyacrylamide beads; and 2) this reactivity is a CD4 T cell dependent, macrophage dependent, B cell independent response which is antigenically specific for parasite egg antigens. We report here on idiotype - anti-idiotype receptor interactions involved in the regulation of granulomatous hypersensitivity in patients and former patients infected with S. mansoni. Five human monoclonal antibodies specific for parasite egg antigens were used to activate CD4 and CD8 T cell subsets. These activated anti-idiotypic T cells were then assayed for regulatory effector functions in an autologous in vitro granuloma model.