Antibodies to the amino-terminal domain of desmoglein 1 are retained during transition from pemphigus vulgaris to pemphigus foliaceus.
BACKGROUND
Pemphigus vulgaris (PV) and pemphigus foliaceus (PF) are two blistering skin diseases mediated by antibodies to desmoglein 3 (Dsg3) and/or Dsg1. Phenotypic transition from PV to PF is rarely reported.


OBJECTIVE
To determine the immune response to extracellular (EC) domains of Dsgs during this transition.


METHODS
We report two PV patients who subsequently developed a PF phenotype. To map the conformational epitopes in these cases, we examined the reactivity of the sera of two patients by immunoprecipitation-immunoblotting analysis, using five Dsg1/Dsg3 domain-swapped molecules on a backbone of Dsg2.


RESULTS
Reactivity exclusively with the EC1 domain of Dsg1 was maintained in both PV and PF stages. No reactivity to Dsg3 in the PF stage was found in patient 1. Various changes in immunoreactivity to Dsg3 were found and the EC1 and EC2 domains of Dsg3 reacted weakly to serum taken at remission and PF stages in patient 2.


CONCLUSIONS
Our findings suggest that amino-terminal pathogenic antibodies to the EC domain of Dsg1 were retained, while considerable epitope changes occurred in response to Dsg3 during the shift from PV to PF, with an absolute or significant decrease in pathogenic antibodies to the EC1 domain of Dsg3.
Department of Dermatology, University Clinic of Navarra. University of Navarra, PO Box 4209, Pamplona 31080 Navarra, Spain.
Agustín
A
España
Department of Dermatology, Kurume University School of Medicine, Japan.
Hiroshi
H
Koga
Department of Dermatology, Gregorio Marañón Hospital, Universidad Autónoma de Madrid, Spain.
Ricardo
R
Suárez-Fernández
Department of Dermatology, Kurume University School of Medicine, Japan.
Chika
C
Ohata
Department of Dermatology, Kurume University School of Medicine, Japan.
Norito
N
Ishii
Department of Dermatology, University Clinic of Navarra. University of Navarra, PO Box 4209, Pamplona 31080 Navarra, Spain.
Isabel
I
Irarrazaval
Department of Dermatology, Kurume University School of Medicine, Japan.
Kwesi
K
Teye
Department of Dermatology, Kurume University School of Medicine, Japan.
Bungo
B
Ohyama
Department of Dermatology, Kurume University School of Medicine, Japan.
Takashi
T
Hashimoto
D000328:Adult; D001323:Autoantibodies / Q000097:blood*; D051183:Desmoglein 1 / Q000276:immunology*; D051184:Desmoglein 3 / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010392:Pemphigus / Q000097:blood* / Q000276:immunology*
D001323:Autoantibodies; D051183:Desmoglein 1; D051184:Desmoglein 3
acantholysis; desmoglein; desmoglein domain-swapped molecules; immunoblotting/immunoprecipitation; pemphigus foliaceus; pemphigus vulgaris