title: Analysis of Anti-desmoglein 1 Autoantibodies in 68 Healthy Mother/Neonate Pairs from a Highly Endemic Region of Fogo Selvagem in Brazil.
abstract: OBJECTIVE
  Fogo Selvagem (FS) in Limao Verde (LV), Brazil shows clinical and histological features of pemphigus foliaceus (PF) and shares pathogenic IgG4 anti-desmoglein 1 (Dsg1) autoantibodies. Previously, our group reported that mothers with active FS deliver babies with normal skin and low/negative titers of IgG4 autoantibodies by indirect immunofluorescence. It was postulated that maternal pathogenic IgG4 autoantibodies do not cross the placenta due to differential receptor mediated transplacental passage of IgG subclasses. It was also thought that placental Dsg1 may immunoadsorb pathogenic autoantibodies from the mother; hence pathogenic IgG4 autoantibodies do not reach the baby. In this study we use a Dsg1-specific ELISA to test anti-Dsg1 autoantibodies of the IgM, IgG and the IgG subclasses in the sera of 68 pairs of normal mothers and their neonates living in a highly endemic area of FS. Determination of these baseline anti-Dsg1 autoantibodies will allow us to follow and predict in this and other cohorts the appearance of preclinical serological markers of FS.
  
  
  METHODS
  The sera of mothers and neonates living in the endemic region were tested by ELISA for IgM, IgG and IgG subclasses using recombinant Dsg1 and anti-IgG subclass-specific monoclonal antibodies.
  
  
  RESULTS
  The index values of anti-Dsg1 IgG1, IgG2 and IgG3 are similar in mothers and neonates (all p>0.18), while the index values of IgM, total IgG and IgG4 are higher in mothers (all p<0.001).
  
  
  CONCLUSIONS
  Narrowing the IgM, IgG and IgG subclasses of mothers and neonates to autoantibodies against Dsg1, we found, as expected, that IgM remains only in maternal circulation. In three mothers and two neonates we detected IgG4 anti-Dsg1 autoantibodies above the normal range. The remaining IgG subclasses show low values. The results of the neonatal sera will serve as a baseline for ongoing seroepidemiological studies of children and adults in the endemic regions of FS.
authors.affiliation: Departments of Physiology, National University of Trujillo School of Medicine, Peru.
authors.forename: Julio
authors.initials: J
authors.lastname: Hilario-Vargas
authors.affiliation: Departamento de Obstetrics, Universidade Federal de Mato Grosso do Sul, Brazil.
authors.forename: Irineu B
authors.initials: IB
authors.lastname: Vitorio
authors.affiliation: Department of Dermatology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Stamey
authors.affiliation: Department of Dermatology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Donna A
authors.initials: DA
authors.lastname: Culton
authors.affiliation: Department of Dermatology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Phillip
authors.initials: P
authors.lastname: Prisayanh
authors.affiliation: Departamento de Dermatologia, Universidade de Sao Paulo, Brazil.
authors.forename: Evandro A
authors.initials: EA
authors.lastname: Rivitti
authors.affiliation: Departamento de Dermatologia, Universidade de Sao Paulo, Brazil.
authors.forename: Valeria
authors.initials: V
authors.lastname: Aoki
authors.affiliation: Departamento de Dermatologia, Universidade Federal de Mato Grosso do Sul, Brazil.
authors.forename: Gunter Hans
authors.initials: GH
authors.lastname: Filho
authors.affiliation: Departamento de Dermatologia, Universidade Federal de Mato Grosso do Sul, Brazil.
authors.forename: Vandir
authors.initials: V
authors.lastname: Dos Santos
authors.affiliation: Department of Biostatistics, University of North Carolina at Chapel Hill, NC, USA.
authors.forename: Bahjat
authors.initials: B
authors.lastname: Qaqish
authors.affiliation: Department of Dermatology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
authors.forename: Luis A
authors.initials: LA
authors.lastname: Diaz
keywords: Autoimmune Bullous Diseases; Fogo Selvagem; Neonatal Autoimmunity; Neonatal Pemphigus; Pemphigus Foliaceus; Pemphigus Vulgaris