T-cell differentiation and effector functions.

T cells and their subpopulations have many different functions important for (i) the regulation of immune responses through the release of antigen non-specific lymphokines and (ii) as effector cells to rid the host of intracellular pathogens, be they bacteria, parasites or viruses. In this short summary only a few features of T-cell function can be summarized, and studies in virus infection will serve as illustrations.