Identification of bullous pemphigoid, pemphigus, laminin, and anchoring fibril antigens in human fetal skin.

Human fetal skin was evaluated for sequential and regional development of several epidermal antigens. Indirect immunofluorescent methods were used to detect laminin, bullous pemphigoid antigen, pemphigus antigen, and anchoring fibril antigens identified by monoclonal antibodies AF1 and AF2. Eighty-three human fetal skin biopsies from 32 human fetuses were examined. The fetuses examined ranged from estimated gestational age (EGA) of 7-38 weeks. Laminin was present in the basement membrane zone of all the fetal tissues examined. Bullous pemphigoid antigen developed first in the palm and sole, 9 weeks EGA, and was present in all other sites by 17 weeks EGA. Pemphigus antigen was present by 11 weeks EGA. AF1 and AF2 staining was not present until 26 weeks EGA, AF1 and AF2 stained epidermal basal cells in addition to the basement membrane zone area. Comparison of human fetal skin development with basal cell carcinoma identified similarities between basal cell carcinoma and early fetal development.