title: The IgM anti-desmoglein 1 response distinguishes Brazilian pemphigus foliaceus (fogo selvagem) from other forms of pemphigus.
abstract: Fogo selvagem (FS) and pemphigus foliaceus (PF) possess pathogenic IgG anti-desmoglein 1-(Dsg1) autoantibodies. Although PF occurs sporadically, FS is endemic in Limao Verde (LV), Brazil (3.4% prevalence). IgM anti-Dsg1 were detected in 58% FS LV patients (n=31), 19% of FS patients from Hospital-Campo Grande (n=57), 19% from Hospital-Goiania (n=42), 12% from Hospital-Sao Paulo (n=56), 10% of PF patients from United States (n=20), and 0% of PF patients from Japan (n=20). Pemphigus vulgaris (n=40, USA and Japan), bullous pemphigoid (n=40, USA), and healthy donors (n=55, USA) showed negligible percentages of positive sera. High percentages of positive IgM anti-Dsg1 were found in healthy donors from four rural Amerindian populations (42% of 243) as compared with urban donors (14% of 81; P<0.001). More than 50% of healthy donors from LV (n=99, age 5-20 years) possess IgM anti-Dsg1 across ages, whereas IgG-anti-Dsg1 was detected in 2.9% (age 5-10 years), 7.3% (age 11-15 years), and 29% of donors above age 16. IgM anti-Dsg1 epitopes are Ca2+ and carbohydrate-independent. We propose that IgM anti-Dsg1 are common in FS patients in their native environment and uncommon in other pemphigus phenotypes and in FS patients who migrate to urban hospitals. Recurrent environmental antigenic exposure may lead to IgM and IgG responses that trigger FS. JID JOURNAL CLUB ARTICLE: For questions, answers, and open discussion about this article please go to http://network.nature.com/group/jidclub.
authors.affiliation: Department of Dermatology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA. ldiaz@med.unc.edu
authors.forename: Luis A
authors.initials: LA
authors.lastname: Diaz
authors.forename: Phillip S
authors.initials: PS
authors.lastname: Prisayanh
authors.forename: David A
authors.initials: DA
authors.lastname: Dasher
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.forename: Flor
authors.initials: F
authors.lastname: Evangelista
authors.forename: Valeria
authors.initials: V
authors.lastname: Aoki
authors.forename: Gunter
authors.initials: G
authors.lastname: Hans-Filho
authors.forename: Vandir
authors.initials: V
authors.lastname: dos Santos
authors.forename: Bahjat F
authors.initials: BF
authors.lastname: Qaqish
authors.forename: Evandro A
authors.initials: EA
authors.lastname: Rivitti
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000097:blood*; D002118:Calcium / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D051183:Desmoglein 1 / Q000276:immunology*; D003937:Diagnosis, Differential; D019353:Endemic Diseases / Q000706:statistics & numerical data*; D004817:Epidermis / Q000276:immunology; D000939:Epitopes / Q000276:immunology; D005260:Female; D006031:Glycosylation; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008297:Male; D008875:Middle Aged; D010392:Pemphigus / Q000175:diagnosis / Q000453:epidemiology* / Q000276:immunology*; D012424:Rural Population / Q000706:statistics & numerical data; D016036:Seroepidemiologic Studies; D014505:Urban Population / Q000706:statistics & numerical data
chemical_list: D001323:Autoantibodies; D051183:Desmoglein 1; D000939:Epitopes; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D002118:Calcium