A three-tiered view of the role of IgA in mucosal defense

Immunol Today. 1993 Sep;14(9):430-5. doi: 10.1016/0167-5699(93)90245-G.


Mucosal IgA has generally been viewed as an immune barrier to prevent the adherence and absorption of antigens. Recent studies employing polarized epithelial monolayers have suggested two additional functions for mucosal IgA. One is to neutralize intracellular microbial pathogens, such as viruses, directly within epithelial cells. The second is to bind antigens in the mucosal lamina propria and excrete them through the adjacent epithelium into the lumen, thereby ridding the body of locally formed immune complexes and decreasing their access to the systemic circulation.

Publication types

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

MeSH terms

  • Animals
  • Antigen-Antibody Complex / immunology
  • Bacterial Infections / immunology
  • Cell Line
  • Epithelium / immunology
  • Humans
  • Immunity
  • Immunoglobulin A / immunology*
  • Mucous Membrane / immunology*
  • Virus Diseases / immunology


  • Antigen-Antibody Complex
  • Immunoglobulin A