T cell suppressionin vitro. II. Nature of specific suppressive factor

摘要

AbstractThe mechanism of specific T cell suppressionin vitrowas investigated. It was found that suppression of hapten‐reactive B cells only occurred in the presence of hapten linked to the carrier to which the T cells were reacting. Thus, there was the same requirement for linked recognition in T cell suppression as was previously described in cooperation. The nature of the suppressive factor was investigated, and like the cooperating factor, it was found to have specificity for the immunizing carrier protein and to be fully absorbed by peritoneal macrophages. The ratio of helper to suppressor activity obtained from activated T cells did not change between 4 and 8 days after injection of antigen and thymocytes. Both activities were absorbed by Sepharose beads conjugated with polyvalent anti‐mouse Ig, anti‐ϰ or anti‐μ‐chain antibody. There was thus a resemblance between the T cell suppressive factor and the immunizing factor, although it is not yet known whether both properties are expressed by one and the same molecule. This must await further biochemical characterization of specific T c