Bullous pemphigoid: correlation of mucosal involvement and mucosal expression of autoantigens studied by indirect immunofluorescence and immunoblotting

Twenty patients with bullous pemphigoid were studied prospectively: sequent ial sera, in different phases of the disease, were collected over a period of approximately 2 years. the sera were tested using standard immunofluores cence techniques with salt-split and intact human tissue fi om different si tes of the body (thigh, breast, oral mucosa, vagina): an early serum. of ea ch patient was tested by Western blotting. The concentration of circulating antibodies detected by the intact skin and intact mucous membranes was sim ilar; split tissue was more sensitive than intact tissue. For eight of 19 p atients, split vagina and occasionally split oral mucosa (in the same patie nts) were much less sensitive than all other tissues. Furthermore, there wa s a correlation between autoantibody reactivity with split mucous membrane tissues and clinical mucosal involvement. These results strongly suggest he terogeneity of antigens or epitopes expressed between tissues. In both spli t skin and mucosa all sera consistently detected an antigen on the epiderma l side of the split regardless of the stage of the disease. Immunoblotting studies showed no correlation between specific antigens and mucosal express ion or skin involvement.