Pemphigus foliaceus autoantibodies bind both epidermis and squamous mucosal epithelium, but tissue injury is detected only in the epidermis. The Cooperative Group on Fogo Selvagem Research.

BACKGROUND: Fogo selvagem (FS) is an autoimmune intraepidermal blistering disease mediated by antidesmosomal autoantibodies. Patients with FS do not have mucosal lesions despite extensive skin involvement. OBJECTIVE: Our purpose was to evaluate the epidermis and the oral epithelium of patients with FS as targets of antidesmosomal autoantibodies. METHODS: Fifteen patients were studied clinically, histologically, and immunologically. Biopsy specimens from the skin and the oral mucosa were studied by light microscopy and direct immunofluorescence. The serum of each of these patients was also titrated by indirect immunofluorescence. RESULTS: All patients showed skin lesions and subcorneal acantholyis, but none exhibited oral blisters or erosions. Direct immunofluorescence analysis demonstrated the presence of tissue-bound autoantibodies in both the epidermis and the oral epithelium of all patients with FS. Antiepidermal autoantibodies were also found in the sera of the patients. CONCLUSION: Relevant epitopes on desmoglein 1 molecules of oral epithelium may not be available to react with pathogenic FS autoantibodies.

Cutaneous lupus erythematosus: direct immunofluorescence and epidermal basal membrane study.

Biopsy specimens of cutaneous discoid lesions of 71 patients with cutaneous lupus erythematosus (CLE) were studied. The material was examined by direct immunofluorescence (DIF) to establish positivity and morphologic patterns of immunoglobulins and complement deposits in the basement membrane zone (BMZ). A correlation between DIF results and thickening of the epidermis basement membrane (BM) stained by periodic acid-Schiff (PAS), obtained from 31 matched biopsy specimens, also is presented. Direct immunofluorescence had positive results in 66.20% of the 71 examinations and 70.97% of the matched examinations, whereas PAS showed BM thickening in 100% of the specimens. This observation stresses the importance of such histopathologic findings in the diagnosis of discoid lesions in CLE. There was no correlation between DIF patterns and PAS-stained BMZ thickening. These findings merit additional study. In conclusion, an accordance between PAS-stained BM thickening and immunoglobulin deposits has occurred in 70.97% of cases. This phenomenon does not depend on the presence of immunocomplexes, for it occurs even in cases in which immunocomplex deposits were not detected.

[Immunopathological studies in herpes gestationis]. / Estudos de inmunopatologia no herpes gestationis.

Immunologic studies were made in two patients with "herpes gestationis". Direct and indirect immunofluorescence studies lead to the following results: 1. DIF was done with antisera against IgG, IgM, IgA, IgE and C3. Only the deposit of C3 was detected on the basal membrane zone of the lesioned skin. In one of the patients the deposit was found also on healthy skin. 2. IIF did not show immunoglobulins against the basal membrane in sera but in both patients a termolabil factor (factor HG) which activates the fixation of the complement onto the basal membrane zone was detected. No correlation between the immunopathologic pattern of Herpes gestationis and that of the other bullous diseases which cause subepidermic bullae was found. However there was a significant similarity between the immunologic pattern of Herpes gestationis and Bullous pemphigoid.