TSP-1 is increased in the involved forearm skin of SSc patients. Skin biopsies from SSc patients and healthy controls (n = 5 for each group) were stained by immunohistochemistry using a primary antibody against TSP-1. In healthy controls, positive staining was seen around endothelial cells in the dermis. In SSc sections, TSP-1 was increased and expressed in endothelial cells, epidermal keratinocytes and cells of the dermis. Isotype-matched antirabbit IgG polyclonal antibody was included as a control.