Herpes gestationis autoantibodies recognize a 180-kD human epidermal antigen

Herpes gestationis (HG) is a putative autoimmune bullous dermatosis of pregnancy which shares many findings with bullous pemphigoid (BP), a disease of the elderly. This study identifies for the first time the antigen detected by HG autoantibodies and compares it with that recognized by BP autoantibodies. Sera from 16 HG and 17 BP patients, and from normal pregnant women were evaluated by immunofluorescent (IF) studies and immunoblotted against human epidermal extracts. 89% of HG sera with circulating antibodies by IF recognized a 180-kD protein by immunoblotting. 71% of BP sera recognized a 240-kD band, but 47% detected a 180-kD protein that comigrated with the antigen detected by HG sera. None of the control sera recognized any specific bands. These findings suggest that the 180-kD epidermal protein may be the antigen detected by the HG factor and they also define immunologic similarities between HG and BP.