Natural antimicrobial production by the amnion.

Department of Obstetrics and Gynaecology, University of Edinburgh, Centre for Reproductive Biology, Queen's Medical Research Institute, Edinburgh, UK.
American journal of obstetrics and gynecology (Impact Factor: 3.28). 03/2007; 196(3):255.e1-6. DOI: 10.1016/j.ajog.2006.10.908
Source: PubMed

ABSTRACT The purpose of this study was to determine the expression of natural antimicrobials in primary cultured amnion epithelial cells and to examine their regulation by interleukin-1 beta (IL-1beta).
Primary amnion epithelial cells were cultured from samples that were obtained at prelabor cesarean section (n = 12) and stimulated with IL-1beta. Natural antimicrobial messenger RNA expression was determined by real-time quantitative polymerase chain reaction, and protein was measured by enzyme-linked immunosorbent assay. Data was analyzed by analysis of variance.
Primary amnion epithelial cells express messenger RNA for human beta defensin (HBD) 1 to 3, secretory leukocyte protease inhibitor and elafin, but not HBD4. IL-1beta 10 ng/mL stimulates HBD2 messenger RNA in a biphasic pattern, with a 51-fold increase at 6 hours and a 67-fold at 12 hours (P < .001). HBD2 protein production is significantly increased by 24 hours (P < .05).
The amnion produces potent natural antimicrobials that may help protect the pregnancy from infection. HBD2 production is dramatically upregulated by the labor-associated inflammatory cytokine IL-1beta.

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