Pathophysiological pathways in bullous pemphigoid. Many of these pathways have been demonstrated in mouse models. Although neutrophils are critical for subepidermal blisters in the mouse, in humans the infiltrate is usually eosinophil rich, with many fewer neutrophils. Abbreviations: BMZ, basement membrane zone; BP, bullous pemphigoid; EC, ectodomain; Ig, immunoglobulin; MC, mast cell; NE, neutrophil elastase.