Suppressive and Enhancing T-cell Factors as I-region Gene Products: Properties and the Subregion Assignment

Abstract

This paper describes two distinct antigen-specific T-cell factors having opposite functions in the regulation of antibody response, one suppressive and the other enhancing for a T-cell-dependent antibody response. Both factors are found to have I-region gene expressions. Available evidence indicates that they are coded for by genes present in distinct I subregions, and that the targets for these factors are probably T cells also carrying I-region determinants. Incorporating the new target cell type in the network of immunocompetent cell interactions, possible mechanisms of T-cell-mediated regulation of antibody response will be discussed.