Abstract: Objective To detect the target antigens of basal membrane zone antibodies (BMZ-Ab) in linear IgA bullous dermatosis (LABD). Methods Dermal and epidermal antigens were extracted by heat-separated procedure, then the target antigens of BMZ-Abs in 11 LABD sera were detected. Results The IgA BMZ-Abs in 9/11 LABD sera could reacted with dermal and epidermal antigens respectively. 7/11 LABD sera reacted with 97 000 epidermal antigen (LABD 97), 2 sera reacted with 180 000 epidermal antigen simultaneously. 2 adult LABD sera recognized 180 000 and 230 000 epidermal antigen respectively. IgG BMZ-Ab in 5/11 LABD sera reacted with 97 000, 145 000, 180 000, 230 000 epidermal antigens, and did not react with dermal antigens. Conclusions The target antigens of IgA BMZ-Abs in LABD were heterogeneous including LABD 97, BP 180 and BP 230. LABD 97 may be a degraded fragment of BP 180. Whether LABD is an independent entity or not should be further investigated.

Key words: Linear IgA bullous dermatosis, Blotting, Western