Lactobacillus acidophilusContributes to a Healthy Environment for Vaginal Epithelial Cells

Abstract

Lactobacillus species in the female genital tract are thought to act as a barrier to infection. Several studies have demonstrated that lactobacilli can adhere to vaginal epithelial cells. However, little is known about how the adherence of lactobacilli to vaginal epithelial cells affects the acidity, cell viability, or proliferation of the lactobacilli themselves or those of vaginal epithelial cells. Lactobacillus acidophilus was co-cultured with immortalized human vaginal epithelial cells (MS74 cell line), and the growth of L. acidophilus and the acidity of the culture medium were measured. MS74 cell density and viability were also assessed by counting cell numbers and observing the cell attachment state. L. acidophilus showed exponential growth for the first 6 hr until 9 hr, and the pH was maintained close to 4.0-5.0 at 24 hr after culture, consistent with previous studies. The growth curve of L. acidophilus or the pH values were relatively unaffected by co-culture with MS74 cells, confirming that L. acidophilus maintains a low pH in the presence of MS74 cells. This co-culture model could therefore potentially be used to mimic vaginal conditions for future in vitro studies. On the other hand, MS74 cells co-cultured with L. acidophilus more firmly attached to the culture plate, and a higher number of cells were present compared to cells cultured in the absence of L. acidophilus. These results indicate that L. acidophilus increases MS74 cell proliferation and viability, suggesting that lactobacilli may contribute to the healthy environment for vaginal epithelial cells.

In-depth insights into cervicovaginal microbial communities and hrHPV infections using high-resolution microbiome profiling

“…In fact, our findings hint that L. acidophilus is possibly associated with the abundance of specific bacterial species. This finding agrees with studies that have shown that L. acidophilus occurrence associates with a healthy cervix and a protective immune response, which may indicate its ability to enhance beneficial Lactobacillus species such as L. crispatus 41 – 44 . Alternatively, L. acidophilus occurrence may also lead to a decrease in the abundance of Lactobacillus species that generally dominate the CVM, facilitating the colonization by other microbes, an increase in diversity, and the transition to a different CST.…”

Lactobacillus Decelerates Cervical Epithelial Cell Cycle Progression

“…However, only the gastric-isolated L. rhamnosus was able to produce an effect on cell proliferation through the sufficient reduction of the pH of the cell medium. By contrast, despite the fact that L. acidophilus reduces the cell medium to a pH of 4.5, this bacterial species has been reported to increase the proliferation of human vaginal epithelial cells [14]. Lactic has been shown to cause cell cycle arrest and apoptosis in human keratinocyte cells [15].…”

Lactobacillus fermentum ATCC 23271 Displays In vitro Inhibitory Activities against Candida spp.

“…Interaction with mucin allows the lactobacilli to remain within the mucus layers, thereby contributing to the formation of multi-species biofilms (Wickstrom et al, 2013), which are essential for protection against intruding pathogens (Pi et al, 2011). Amongst the tested Lactobacillus species, L. fermentum ATCC 23271 was the only to produce moderate biofilm on plastic surface in comparison with other lactobacilli.…”