Nylon adherent antigen-specific rosette-forming T cells.

Abstract

Shortly after i.v. immunization of mice with heterologous [sheep, horse] erythrocytes (RBC) antigen-specific Thy 1+ cells which form rosettes with the immunizing RBC (thymus-derived lymphocytes-forming rosettes [T-RFC]) appear in the spleen. These T-RFC are much less stable than Thy 1- RFC (non-thymic-derived [B[bone-marrow derived]-RFC]) although most if not all of both classes of RFC adhere to nylon. T-RFC are induced with low doses of antigen (which fail to induce B-RFC) and are inhibited by higher antigen doses which are optimal for induction of B-RFC. Pretreatment of mice with cyclophosphamide prevents the high dose inhibition of T-RFC. Although there are many parallels between the production of T-RFC and delayed-type hypersensitivity (DTH) it is unlikely that the T-RFC are essential for DTH reactions since DTH can be transferred with cells which pass through nylon, and such cells are almost totally depleted of T-RFC. Immunization can lead to the production of large numbers of antigen-specific T-RFC whose functional role in the immune response is unknown. The characteristics of the T-RFC suggest that they may play an important role in amplification of suppressor cell activity.