Regulation of lymphocyte functions by nitric oxide.

Current interest in nitric oxide is derived from its numerous biological roles. Immunologically, apart from the well known role of nitric oxide in anti-microbial and autoimmune diseases, nitric oxide is now emerging as a potential powerful mediator of T-cell responses. Evidence now shows that nitric oxide can both enhance and suppress T-cell functions and that some subsets of T-cell clones can be activated to produce nitric oxide.