IgG4 and IgE are the major immunoglobulins targeting the NC16A domain of BP180 in Bullous pemphigoid: serum levels of these immunoglobulins reflect disease activity.
BACKGROUND
Bullous pemphigoid (BP) is an autoimmune blistering disease associated with autoantibodies against the hemidesmosomal glycoprotein BP180. The noncollagenous (NC)16A domain of BP180 has recently been shown to harbor major antigenic sites recognized by BP sera.


OBJECTIVE
The purpose of this study was to characterize the subclass distribution and fine specificities of autoantibodies to BP180 NC16A present in the circulation of patients with BP before, and during the course of, therapy for this disease.


METHODS
Eighteen BP sera were analyzed by immunoblotting and enzyme-linked immunosorbent assay for the presence of IgG1, IgG2, IgG3, IgG4, and IgE reactive with various sites on the BP180 NC16A domain. The sera were collected before treatment was started and at 4- and 8-week time points after initiation of treatment.


RESULTS
We identified IgG4 and IgE as the major immunoglobulins that preferentially react with two distinct epitopes (MCW-1 and MCW-2) within BP180 NC16A. Levels of these autoantibodies correlated with disease activity in BP. During the course of disease, no change was observed with regard to the immunoglobulin subclass predominantly reacting with BP180 NC16A or the specific epitopes within this domain.


CONCLUSIONS
Our data demonstrate that remission of BP is paralleled by a decrease of serum levels of IgE and the different IgG subclasses reactive with BP180 NC16A.
Döpp
R
R
Department of Dermatology, University of Würzburg, Germany.
Schmidt
E
E
Chimanovitch
I
I
Leverkus
M
M
Bröcker
E B
EB
Zillikens
D
D
D000368:Aged; D000918:Antibody Specificity; D001323:Autoantibodies / Q000097:blood / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology*; D002352:Carrier Proteins; D003094:Collagen / Q000276:immunology*; D003598:Cytoskeletal Proteins; D000071821:Dystonin; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000276:immunology; D005260:Female; D006801:Humans; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D008297:Male; D009419:Nerve Tissue Proteins; D024041:Non-Fibrillar Collagens; D010391:Pemphigoid, Bullous / Q000097:blood / Q000175:diagnosis / Q000276:immunology*; D000097805:Collagen Type XVII
D001323:Autoantibodies; D001324:Autoantigens; D002352:Carrier Proteins; D003094:Collagen; D003598:Cytoskeletal Proteins; D000071821:Dystonin; D000939:Epitopes; D007073:Immunoglobulin E; D007074:Immunoglobulin G; D009419:Nerve Tissue Proteins; D024041:Non-Fibrillar Collagens; D000097805:Collagen Type XVII; C486268:DST protein, human