[Lymphokines, interleukins, cytokines: function and action].

In the present review major lymphokines and monokines as well as their biological role in the specific immune response are summarized. Using as an example the generation of cytolytic T-lymphocytes, the interplay between antigen and interleukin is discussed. Although the signal transmission pathways and secondary messengers in interleukin-mediated cell activation have not been fully elucidated, principle mechanisms with possible relevance for interleukin activity are presented. Due to the broad spectrum of interleukin activities as well as their target and producer cells, future definition of interleukins should be based on functional and structural features.