title: IgG to various beta-glucans in a human adult population.
abstract: BACKGROUND
  Fungal β-(1,3)-glucans are pro-inflammatory agents, and exposures to β-(1,3)-glucans are associated with respiratory tract symptoms. IgG anti-(1,3)-glucan titers are measured in diagnosis of fungal infections. Although other β-glucan structures exist, like β-(1,6)-glucans, little is known about their antigenic or pro-inflammatory properties. We aimed to investigate IgG titers and specificities in human sera against different β-glucans with varying structures.
  
  
  METHODS
  IgG anti-β-glucan was measured by enzyme immunoassay in a random sample of 40 sera from healthy adults, with a panel of 8 differently structured glucans. In a subsequent larger series, IgG anti-β-(1,6)-glucan was measured in a random sample of 667 sera from three occupational populations with different organic dust exposures. Possible determinants of IgG anti-β-(1,6)-glucan titers were explored with linear-regression analysis.
  
  
  RESULTS
  We found wide variation in anti-β-glucan IgG levels. The highest titers were found for pure β-(1,6)-glucan pustulan. Moderate to strong reactions with other β-(1,6)-containing structures appeared to be due to cross-reacting anti-β-(1,6)-glucan antibodies. Surprisingly, the mean IgG anti-β-(1,6)-glucan titer was significantly lower in agricultural workers - with highest organic dust exposure - than in spray painters and bakery workers. Smoking status was associated with lower IgG anti-β-(1,6)-glucan titers in all populations.
  
  
  CONCLUSIONS
  IgG to β-(1,3)- and β-(1,6)-glucans can be found in normal human sera. β-(1,6)-glucans appear to be much more potent antigens. The health impact of high anti-β-(1,6)-glucan antibody levels remains unclear and further investigations are needed.
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Ilka
authors.initials: I
authors.lastname: Noss
authors.forename: Inge M
authors.initials: IM
authors.lastname: Wouters
authors.forename: Lidwien A M
authors.initials: LA
authors.lastname: Smit
authors.forename: Evert
authors.initials: E
authors.lastname: Meijer
authors.forename: Anjoeka
authors.initials: A
authors.lastname: Pronk
authors.forename: Dick J J
authors.initials: DJ
authors.lastname: Heederik
authors.forename: Gert
authors.initials: G
authors.lastname: Doekes
mesh_terms: D000328:Adult; D000395:Air Pollutants, Occupational / Q000276:immunology; D000918:Antibody Specificity; D003429:Cross Reactions / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood* / Q000276:immunology*; D008172:Lung Diseases, Fungal / Q000453:epidemiology / Q000276:immunology; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure; D011485:Protein Binding / Q000276:immunology; D047071:beta-Glucans / Q000737:chemistry / Q000276:immunology*
chemical_list: D000395:Air Pollutants, Occupational; D007074:Immunoglobulin G; D047071:beta-Glucans