Dendritic cell production of cytokines and responses to cytokines.

Dendritic cells (DC) are a family of bone marrow-derived MHC class II expressing cells which occur in small numbers in most lymphoid and nonlymphoid tissues. They represent a distinct lineage of leukocytes which can be found in two distinct maturational stages: immature dendritic cells are exemplified by the Langerhans cells in the epidermis, and are considered to be precursors to the mature dendritic cells in the lymphoid organs. These maturational stages can be distinguished by phenotypic and functional characteristics. Immature dendritic cells are weak stimulators of resting T lymphocytes but are excellent in processing soluble protein antigens for presentation to T cell clones. Mature dendritic cells show exactly reciprocal features. In this review the relatively few available data on cytokine production by DC and responses of DC to cytokines are collected. Our goal is to consider the role of cytokines in DC function including the transition from immature to mature stages.