[Fibrocytes and fibroblasts. Definition and significance in wound healing and fibrotic diseases of the skin].

Fibroblasts are not only responsible for connective tissue synthesis in the dermis, but in addition have to fulfill several functions including chemotaxis, attachment and proliferation as well as tissue remodelling. They interact with various molecules of the extracellular matrix which to a certain extent can regulate some of these cellular functions. Furthermore fibroblast metabolism is influenced by cytokines released by other cells. Some of these factors e.g. TNF, TGF-beta or interferon-y have been shown to regulate specifically some functions whereas others can modulate the cellular differentiation. An exact knowledge of the interaction with the extracellular matrix and the response to various cytokines released during pathological conditions is required for the understanding of altered fibroblast metabolism leading to wound healing defects or fibrosis.