Abstract
Human milk leukocytes contain large quantities of IgA and other proteins. During prolonged in vitro incubation, the IgA is released. To further examine the potential role of this process in delivering these proteins to the recepient infant, the effect of phagocytosis upon the release of IgA from colostral leukocytes was investigated. Washed leukocytes were incubated with live Escherichia coli or heat-killed Candida albicans in the presence or absence of serum opsonins. The degree of phagocytosis was determined microscopically. Controls were incubated without particles. After 15, 30, and 60 minutes, cells and supernatant fluids were recovered and assayed for total IgA and SIgA by a quantitative immunofluorescence assay. The degree of IgA release was enhanced (approximately 40%) with cells exposed to opsonized organisms, as compared to preparations containing no particles. The degree of decrease in the IgA level in the cell lysates was paralleled by an increase in IgA in the supernatant fluids from the cell preparations. In contrast, little release occurred (approximately 4%) with unopsonized organisms. The enhanced release was evident within 15 minutes. Cells incubated with opsonized organisms at 4°C did not release IgA until warmed. The enhanced release of IgA by colostral leukocytes during phagocytosis may be part of a mechanism to deliver IgA antibodies to the site of microbial colonization or infection in the infant.
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Weaver, E., Goldman, A., Goldblum, R. et al. 974 COLOSTRAL CELLS: IgA RELKASE STIMULATED DURING PHAGOCYTOSIS. Pediatr Res 15 (Suppl 4), 605 (1981). https://doi.org/10.1203/00006450-198104001-00999
Issue Date:
DOI: https://doi.org/10.1203/00006450-198104001-00999