Recognition of idiotypes in lymphocyte interactions II. Antigen‐independent cooperation between T and B lymphocytes that possess similar and complementary idiotypes

摘要

AbstractAntigen‐independent cooperation between T and B lymphocytes is demonstratedin vitroin two different experimental protocols: (a) B cells from A/J mice immunizedin vivoeither with Group A streptococcal vaccine (Strep.A) or with the IgG1fraction of guinea pig anti‐idiotypic antibody to the A5A idiotype, mature into plaque‐forming cells (PFC) with specificity for Group A streptococcal carbohydrate (A‐CHO) during a 4‐day culture together with T cells from A/J mice immunizedin vivowith A5A idiotypic antibody. (b) B cells from A/J mice immunizedin vivowith Strep.A generate PFC specific for A‐CHO when cultured in the presence of small concentrations of anti‐A5A idiotypic antibody and of T cells primed with Strep.A. In both cases, antigenindependent cooperation is idiotypically selective, such that only those B cells respond that secrete antibody with the A5A idiotype.The data are interpreted to suggest that, in addition to antigen‐specific helper cells, idiotype‐specific may participate in antibody responses, and that the latter type of help may be responsible for the idiotypic selectivity in T‐B cooperation observed previously. Furthermore, idiotype‐specific cooperation may be a means to generate and maintain B cell diversity during the evolution and ontogeny