Cell adhesion molecules in inflammatory and neoplastic skin diseases

Cell adhesion molecules (CAMs) are cell surface glycoproteins expressed on several different cell lineages and involved in cell‐cell and cell‐matrix interactions in various physiological and pathological conditions. Numerous studies have shown that CAMs, a very substantial class of molecules subdivided into four families (integrins. the immunoglobulin‐gene family, cudherins and lectin‐like CAMs). are involved in the interaction of lymphocytes with keratinocytes, endothelial ceils and inter‐and perivascular connective cells. Researchers have found a marked increase in the expression of CAMs with respect to normal skin in a variety of dermatoses, such as cutaneous necrotizing vasculitis. capillarities from unknown origin (purpura pigmentosa chronica). alopecia areata, lichen planus, systemic selerosis, psoriasis, etc. In the inflammatory and neoplastic skin diseases considered in this review, the adhesion molecules found to be chiefly expressed are ELAM‐1, ICAM‐I and LFA‐I. This suggests that, predominantly, these adhesion molecules participate in the complex pathogenetic mechanisms conditioning the onset and development of these diseases. Knowledge of interaction mechanisms has led to identification of the role played by CAMs in the pathogenesis of these diseases and may represent a useful aid in the diagnosis and perhaps treatment of numerous skin pathologies.