Bacterium-induced cleavage of IgA in nasopharyngeal secretions from atopic children

Acta Pathol Microbiol Immunol Scand C. 1984 Feb;92(1):85-7. doi: 10.1111/j.1699-0463.1984.tb00056.x.


Immunoglobulin A forms the specific immune barrier of mucosal surfaces against microorganisms and potential allergens. Immunochemical studies of nasopharyngeal secretions (NPS) from 97 children showed enzymatic degradation of IgA in 18.6% of the samples. The observed fragments are characteristically released from IgA by the activity of specific IgA 1 proteases produced by certain bacterial species. A significantly higher prevalence (P less than 0.001) of IgA cleavage was observed in NPS from children with atopic diseases (61.5%) than in controls (11.9%). These results indicate that bacterium-induced local defects in the mucosal immune barrier of the upper respiratory tract may be a factor in the pathogenesis of some forms of atopic disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Infections / complications*
  • Child, Preschool
  • Humans
  • Hypersensitivity, Immediate / complications
  • Hypersensitivity, Immediate / immunology*
  • Immunoglobulin A / metabolism*
  • Immunoglobulin Fc Fragments / analysis
  • Nasopharynx / immunology
  • Nasopharynx / metabolism*
  • Peptide Hydrolases / metabolism
  • Serine Endopeptidases*


  • Immunoglobulin A
  • Immunoglobulin Fc Fragments
  • Peptide Hydrolases
  • Serine Endopeptidases
  • IgA-specific serine endopeptidase