The Biological Role and Clinical Implications of IgA
- 1 November 1994
- journal article
- Published by Oxford University Press (OUP) in Laboratory Medicine
- Vol. 25 (11) , 724-728
- https://doi.org/10.1093/labmed/25.11.724
Abstract
The total body pool of human IgA (3,600–9,100 mg) is larger than that for all other isotypes combined. Most IgA resides in the small and large intestines in the form of polymeric or secretory IgA (slgA). Serum IgA is primarily monomeric and comprises the second highest concentration of any immunoglobulin in the circulation. IgA is composed of two subclasses: IgAl and IgA2. Secretory IgA consists of approximately equal amounts of IgAl and IgAl. Serum IgA is predominantly IgAl (90%). Secretory IgA functions to neutralize toxins, enzymes, and viruses; agglutinate pathogens; inhibit penetration of foreign antigen into the mucosa and attachment; activate the alternate complement pathway; and possibly opsonize pathogens. Secretory IgA is the first line of defense against most infectious agents, and the integrity of the slgA system is important to the health of the individual. The biological role and clinical implications of IgA are discussed.Keywords
This publication has 0 references indexed in Scilit: