The direct fluorescent antibody staining technique was employed to determine the presence of globulin and γ-globulin in biopsy sections and Tzanck preparations obtained from early bullous lesions of six patients with pemphigus vulgaris.
In all instances these globulins were found to be localized in the epidermis composing the bullae. The localization was found to be essentially in the cytoplasm of the epidermal cells, and particularly the acantholytic cells of the bullae.
Appropriate control procedures were used to establish the specificity of the fluoresceintagged rabbit antihuman γ-globulin serum indicating that in vivo binding of γ-globulin occurred in the lesions of patients with pemphigus vulgaris.