Demonstration of the presence of IgA in the human chorioamniotic membrane

Antibacterial properties of human amnion and chorion in vitro

OBJECTIVE

The purpose of the present study was to explore the direct effects of amnion and chorion on bacterial growth in vitro including the antibacterial spectrum. Chorioamniotic membranes were obtained under sterile conditions from 13 healthy women undergoing elective cesarean section at term. Likewise, chorioamniotic membranes were obtained from 10 healthy women with spontaneous vaginal delivery at term. Five strains of Hemolytic streptococci group B (GBS) were tested and one clinical isolate of the following species or bacterial groups: Hemolytic streptococcus group A, Staphylococcus aureus, Staphylococcus saprophyticus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter calcoaceticus and Lactobacillus species. Bacteriological media included (1) blood-agar medium; (2) a transparent agar medium for submerged cultures; and (3) a nutrient broth medium.

RESULTS

An inhibitory effect of fetal membranes against a range of bacteria was found. Consistent results were obtained in experiments with cultures on agar and cultures suspended in agar (membranes from eight women in both studies). In experiments with liquid cultures (seven women) only chorion showed a marginal inhibitory effect. All strains were inhibited, but the most pronounced inhibition was obtained for streptococcus group A, S. aureus and S. saprophyticus by both chorion and amnion.

CONCLUSION

This study demonstrated an inhibitory effect of the fetal membranes on a diverse panel of bacteria

Quantification of immunoglobulin A in chorioamniotic membrane of patients with premature rupture of membranes

OBJECTIVE

The proposal was to study the presence of immunoglobulin A (IgA) in the chorioamniotic membrane of healthy postpartum women with premature rupture of the chorioamniotic membrane (PROM).

METHOD

A single radial immunodiffusion technique was used to quantify the IgA in the chorioamniotic membrane tissues.

RESULTS

The level of IgA was approximately 10 times higher in patients whose membranes had been ruptured for > 10 h (24.58 mg/dl). These results were compared with those of a previously published study where the mean of amount of IgA was 2.52 mg/dl in membranes of patients with rupture < 10 h. Our results show that IgA began to rise after 10-15 h following rupture.

CONCLUSION

Although more studies need to be performed our data indicate that the increasing IgA in our patients after 10 h of latency probably represents the beginning of an ascending colonization of bacteria which could be the source of future infection.