Isolation of pathogenic monoclonal anti-desmoglein 1 human antibodies by phage display of pemphigus foliaceus autoantibodies.
Pemphigus foliaceus (PF) is a blistering disease caused by autoantibodies to desmoglein 1 (Dsg1) that cause loss of epidermal cell adhesion. To better understand PF pathophysiology, we used phage display to isolate anti-Dsg1 mAbs as single-chain variable fragments (scFvs) from a PF patient. Initial panning of the library isolated only non-pathogenic scFvs. We then used these scFvs to block non-pathogenic epitopes and were able to isolate two unique scFvs, each of which caused typical PF blisters in mice or human epidermis models, showing that a single mAb can disrupt Dsg1 function to cause disease. Both pathogenic scFvs bound conformational epitopes in the N terminus of Dsg1. Other PF sera showed a major antibody response against the same or nearby epitopes defined by these pathogenic scFvs. Finally, we showed restriction of the heavy-chain gene usage of all anti-Dsg1 clones to only five genes, which determined their immunological properties despite promiscuous light-chain gene usage. These mAbs will be useful for studying Dsg1 function and mechanisms of blister formation in PF and for developing targeted therapies and tools to monitor disease activity.
Ishii
Ken
K
Department of Dermatology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA.
Lin
Chenyan
C
Siegel
Don L
DL
Stanley
John R
JR
D000368:Aged; D000818:Animals; D000911:Antibodies, Monoclonal / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D001323:Autoantibodies / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D051183:Desmoglein 1 / Q000032:analysis / Q000037:antagonists & inhibitors / Q000276:immunology*; D018604:Epitope Mapping; D000939:Epitopes / Q000276:immunology; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D007135:Immunoglobulin Variable Region / Q000276:immunology / Q000302:isolation & purification; D051379:Mice; D010392:Pemphigus / Q000276:immunology*; D019151:Peptide Library; D012867:Skin / Q000276:immunology
D000911:Antibodies, Monoclonal; D001323:Autoantibodies; D051183:Desmoglein 1; D000939:Epitopes; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region; D019151:Peptide Library