Expression of thrombospondin-1 (TSP1) and its receptor (CD36) in healthy and diseased human skin.

In the present study, an analysis was made of the expression pattern of thrombospondin-1 (TSP1) and its receptor (CD36) in skin biopsies obtained from healthy volunteers and from patients with lichen planus, lupus erythematosus, cutaneous T-cell lymphoma and psoriasis vulgaris. Using monoclonal antibodies against TSP1 in biopsies from the healthy volunteers and from both clinically involved and uninvolved skin of the patients, a specific peroxidase-positive reaction was detected around the sweat glands in the dermis. In all cases investigated, the CD36-positive lesional keratinocytes remained TSP1-negative. These findings favour the hypothesis that CD36-positive keratinocytes might have some functional relevance via oxidized low-density lipoprotein and/or collagen fibrils, without any connection with TSP1.