Immunoglobulins of the Human Amniotic Fluid
Version of Record online: 6 SEP 2011
American Journal of Reproductive Immunology
Volume 42, Issue 4, pages 219–225, October 1999
How to Cite
Quan, C. P., Forestier, F. and Bouvet, J.-P. (1999), Immunoglobulins of the Human Amniotic Fluid. American Journal of Reproductive Immunology, 42: 219–225. doi: 10.1111/j.1600-0897.1999.tb00094.x
- Issue online: 6 SEP 2011
- Version of Record online: 6 SEP 2011
- accepted December 9, 1998.
- Amniotic fluid;
- secretory component;
- secretory immunoglobulin
Quan CP, Forestier F, Bouvet J-P. Immunoglobulins of the human amniotic fluid. AJRI 1999; 42:219–225 © Munksgaard, Copenhagen
PROBLEM: Except for the description of a secretory immunoglobulin (S-Ig) of a low size, no recent study has investigated the molecular status of antibodies in the human amniotic fluid.
METHOD: After separation with a high performance chromatography, we analyzed the different isotypes of amniotic Igs by immunoblotting and ELISA.
RESULTS: IgG is found to be the major isotype and to contain mother-derived tetanus antitoxins. IgA is much less abundant, whereas no IgM can be detected. IgA is monomeric, with a low level of secretory IgA and with various amounts of free secretory component (SC). The presence of a low level of SC-containing immunoglobulin of a low size is confirmed during the last trimester of pregnancy. This molecule contains no α chain but includes a Fabγ fragment noncovalently associated with SC. IgG, IgA, and SC are detected in the fetal urine and, therefore, can reach the amniotic fluid by this route.
CONLUSION: In addition to the predominant maternal IgG, the amniotic fluid contains different molecular forms of fetal immunoglobulins. Their function as an immune barrier against infection and against mother-derived autoantibodies is discussed.