LOCALIZATION OF MONOCYTE CHEMOTACTIC AND ACTIVATING FACTOR (MCAF MCP-1) IN PSORIASIS/

The monocyte chemotactic protein-1 (MCPLF) also termed MCP-1, a strong chemotactic factor towards monocytes, is produced by several cell typ es present in the skin. The in situ presence of MCAF/MCP-1 protein in the skin has, however, not yet been established. Using immunohistochem ical techniques we have investigated the distribution of MCAF in skin from patients with different types of psoriasis and normal healthy vol unteers. We report the novel finding that psoriasis has strong positiv e immunostaining for MCAF located to all the layers of the epidermis, except the stratum granulosum, in pustular, guttate and chronic plaque psoriasis. In the dermis, infiltrating cells in the perivascular aggr egates and the blood vessels stained positive for MCAF. No significant differences were observed between the different subtypes of psoriasis except that strongly positive infiltrating cells were observed in the epidermal pustules in pustular psoriasis. In normals positive stainin g was observed in all the layers of the epidermis and in a few perivas cular cells and blood vessels in the dermis. Where present in normal a nd diseased skin, eccrine ducts of sweat glands and sebaceous glands s tained positive for MCAF. Arrector pill muscles were in all cases nega tive. These findings are consistent with a role for MCAF in attracting inflammatory cells, including monocytes, into the skin in psoriasis.