The function of immunoglobulin A in immunity

J Pathol. 2006 Jan;208(2):270-82. doi: 10.1002/path.1877.


The vast surfaces of the gastrointestinal, respiratory, and genitourinary tracts represent major sites of potential attack by invading micro-organisms. Immunoglobulin A (IgA), as the principal antibody class in the secretions that bathe these mucosal surfaces, acts as an important first line of defence. IgA, also an important serum immunoglobulin, mediates a variety of protective functions through interaction with specific receptors and immune mediators. The importance of such protection is underlined by the fact that certain pathogens have evolved mechanisms to compromise IgA-mediated defence, providing an opportunity for more effective invasion. IgA function may also be perturbed in certain disease states, some of which are characterized by deposition of IgA in specific tissues. This review details current understanding of the roles played by IgA in both health and disease.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Antibodies / immunology
  • Antigens, CD / immunology
  • Autoimmune Diseases / immunology
  • Bacterial Infections / immunology
  • Bacterial Proteins / immunology
  • Humans
  • IgA Deficiency / immunology
  • Immunoglobulin A / chemistry
  • Immunoglobulin A / immunology*
  • Immunoglobulin A, Secretory / biosynthesis
  • Immunoglobulin A, Secretory / immunology
  • Models, Molecular
  • Mucous Membrane / immunology*
  • Receptors, Fc / immunology
  • Receptors, Polymeric Immunoglobulin / immunology
  • Serine Endopeptidases / immunology


  • Antibodies
  • Antigens, CD
  • Bacterial Proteins
  • Fc(alpha) receptor
  • IgA receptor
  • Immunoglobulin A
  • Immunoglobulin A, Secretory
  • Receptors, Fc
  • Receptors, Polymeric Immunoglobulin
  • Serine Endopeptidases
  • IgA-specific serine endopeptidase