The Caspase Pathway as a Possible Therapeutic Target in Experimental Pemphigus

Figure 2

Induction of acantholysis in Balb/c mice and the prevention of blistering by caspase inhibition. The top panel shows representative figures of a negative control Balb/c mouse injected with normal IgG. This mouse did not develop blisters, show IgG deposition along intercellular spaces or initiate apoptosis. The middle panel shows a mouse injected with pemphigus vulgaris IgG that developed macroscopic abdominal and leg blisters. H&E staining shows that blisters were suprabasally located (arrow) with acantholytic cells (arrow), also PV-IgG was deposited in the roof and base (arrow) of the blister, and apoptotic cells are shown in green (arrow) as demonstrated using TUNEL and annexin staining. The bottom panel shows a mouse treated with the Ac-DEVD-CMK peptide prior to pemphigus IgG injection. The skin biopsy was taken 24 h after injection. The animal did not develop blisters despite the PV-IgG deposition along intercellular spaces. The caspase inhibitor blocked apoptosis of keratinocytes (red). PV-IgG: pemphigus vulgaris IgG. H&E: haematoxilin and eosin. IF: immunofluorescence.