Functional Roles of Two Polypeptide Chains that Compose an Antigen-Specific Suppressor T Cell Factor

Abstract

Our previous studies have demonstrated that the suppression of antibody response is mediated by the factor derived from suppressor T cells (Ts). The antigen-specific suppressor factor (TsF) is found to be composed of the two distinct polypeptide chains, one carrying the determinants defined by anti-I-J antibodies (i.e., B10.A(5R) anti-B10.A(3R)) and the other possessing the antigen-binding moiety with the putative constant region determinant (Ct) detected by alloantibodies made by the combination of the Igh allotype congenic mice (i.e., BALB/c anti-CB-20) (1, 2) which are similar to those originally described by F. Owen and her associates (3). Furthermore, the association of these two chains has been shown to be essential for the functional expression of the antigen-specific suppressor factor (1). Thus, it is important to analyse the biological roles of the two polypeptide chains that compose the suppressor factor. In order to clearify these problems mentioned above, a T cell hybridoma with antigen-specific suppressor activity provides useful tools to characterize the active suppressor molecules at the molecular level.