Figure 5.

Mice pretreated with a C5a receptor (C5aR) antagonist develop less severe blistering. Skin lesions, including blisters and erosions covered by crusts on the ear, snout, front leg, and around eyes developed in a control mouse injected with pathogenic IgG (A). A BALB/c mouse pretreated with a C5aR antagonist and subsequently challenged with the same dose of antibodies to type VII collagen (COL7) showed less extensive skin lesions (B). Immunofluorescenc analysis of perilesional skin revealed deposition of rabbit IgG at the dermal–epidermal junction of both mice groups (C,D). Deposits of mouse C5 along the dermal–epidermal junction were weak in the skin of the pretreated (F) vs non-treated mouse (E). Subepidermal cleavage and neutrophil infiltration was extensive in the skin of control mice (G) and less present in the skin of treated mice (H), as revealed by histopathology. Affected body area of C5aRA treated vs control mice is represented as mean ± SEM. *p < 0.05 represents significant difference of disease activity between the two groups (I). These data were obtained from a single experiment (n = 4/group).