Inhibitory Receptors for the Molecules of B7 Family and the Negative Immune Regula

Abstract: Maintenance of lymphocyte homeostasis is regulated by a number of positive and negative costimulatory signals， which determine the thresholds for antigen-specific stimulation of T and B cells. The balance between two kinds of signals ensures an effective response to foreign antigens for host protection， while avoiding inappropriate reaction to self antigens. Intensive investigations on the structure and function of the costimulation-related molecules revealed that important roles are played by the members of B7 family. The negative control activity exerted by the family is tightly dependent on the inhibitory receptors. Three kinds of B7-ligating receptors with down regulatory activity have been identified， including CTLA-4， PD-1 and BTLA. Studies on the inhibitory receptors have provided a better understanding of the mechanisms for immune regulation， which would help to lay a basis for therapeutic applications to human diseases like cancers， autoimmune disorders and transplantation rejection.

CSTR: 32200.14.cjcb.2005.02.0010