Effect of Lactobacillus rhamnosus GR-1 Supernatant on Cytokine and Chemokine Output From Human Amnion Cells Treated With Lipoteichoic Acid and Lipopolysaccharide

Preterm birth occurs in 9% to 13% of all human pregnancies and accounts for 80% of all neonatal morbidities and mortalities. Approximately 40% of all preterm births are idiopathic and about half are associated with infection and/or an activated inflammatory process. Further to studies showing anti-inflammatory effects of supernatant from the probiotic Lactobacillus rhamnosus GR-1 (GR-1), we tested its ability to modulate cytokine and chemokine production from amnion cells in response to stimulation by bacterial wall components, lipopolysaccharide (LPS), and lipoteichoic acid (LTA). Placentae were collected from women undergoing elective cesarean section at term. Amnion cells were cultured for 48 hours to confluence, serum starved for 12 hours, and then treated with GR-1 supernatant (1:20 dilution), followed after 12 hours by LPS (100 ng/mL) or LTA (10 ng/mL) for an additional 12 hours. Both LTA and LPS caused significant increases in the concentration of the pro-inflammatory cytokine, tumor necrosis factor α (TNF-α; 103.9 ± 67.5 pg/mL and 368.3 ± 65.7 pg/mL, respectively) in medium from cultured amnion cells compared to control (<4 pg/mL). There was no significant effect of GR-1 supernatant alone on TNF-α output, but there was significant reduction after LPS treatment. The basal output of the immunomodulatory cytokine, interleukin 6, was 613 ± 170 pg/mL and increased significantly after addition of GR-1 supernatant, LTA, LPS, and combinations of LTA/LPS with GR-1 supernatant. In conclusion, probiotic L rhamnosus GR-1 attenuates the effect of both LPS and LTA in stimulating the output of the pro-inflammatory cytokine TNF-α from mixed cultures of human amnion cells in keeping with previous findings in human trophoblast cells.