Role of cAMP-dependent signal transduction in the control of T lymphocyte activation

The role of cAMP in the regulation of antigen-dependent differentiation of T cells is discussed with consideration of the molecular mechanisms of cAMP effects. Characteristics of activation signal in various T lymphocyte subpopulations determining differential sensitivity to cAMP are reviewed. Specific attention is given to the involvement of the cAMP-dependent messenger system in the formation of the spectrum of secreted cytokines because their level and ratio determine the type of immune response.