Development of infiltrates and inflammatory lesions in the vicinity of sunburn cells (SBCs) in patients with systemic lupus erythematosus (SLE). Haematoxylin eosin (H&E)-stained paraffin sections before and after irradiation with two minimal erythemal doses of ultraviolet B light (UVB). (a-c) Biopsies from a representative control, non-irradiated (a) and 1 (b) and 3 (c) days after irradiation. (d-f) Biopsies from a representative patient with increased influx of cells, non-irradiated (d) and 1 (e) and 3 (f) days after irradiation. Magnifications, ×100. (g) Graph showing semi-quantitative analysis of infiltrate in H&E sections before and up to 10 days after irradiation. Dotted lines indicate mean + two standard deviations of controls. ●, patients (P); ○, controls (C). No significant differences were present between patients and controls on any time point. (h) Inflammatory lesion in a patient with SLE in the vicinity of SBCs 3 days after irradiation. Inflammatory lesions were defined as the presence of category 5 (see Materials and methods) vessel(s) in the dermis, with inflammatory cell infiltration of the epidermal layer coinciding with marked local hydropic degeneration of the basal layer of the epidermis. Insert shows magnification of area with accumulating SBCs. Magnification, ×100. White arrowheads indicate SBCs, and black arrowheads indicate hydropic degeneration.