Immunofluorescence findings in haematoporphyrin-induced keloid

A case of haematoporphyrin-induced keloid is described in which immunofluorescence (IF) revealed antibodies eluted from circulating lymphoid cells directed against fibroblasts. The antibodies eluted belonged to the main Ig classes IgD and IgM and they did not bind complement in vitro. Their possible activity in stimulating fibroblasts is discussed.