Clinical and Personal Lubricants Impact the Growth of Vaginal Lactobacillus Species and Colonization of Vaginal Epithelial Cells: An in Vitro Study.

BACKGROUND: Vaginal lubricants are commonly used during gynecological examinations, during sexual activities, or to alleviate vaginal dryness. Many lubricants contain potentially bacteriostatic or bactericidal agents (parabens, chlorhexidine gluconate, nonoxynol-9). Our objective was to evaluate the impact of lubricants that vary in formulation on the growth and viability of vaginal Lactobacillus species and vaginal epithelial cell (VEC) colonization in an in vitro model. METHODS: Growth curve, disk diffusion, and minimal inhibitory assays were used to determine the impact of lubricants or excipients on the growth of Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus jensenii, and Lactobacillus iners. L. crispatus strain was used in VEC colonization assays. Statistical differences were determined by analysis of variance. RESULTS: Lubricants containing chlorhexidine gluconate or nonoxynol-9 (N-9; Conceptrol, K-Y Jelly, and Surgilube) significantly inhibited Lactobacillus species growth (P < 0.05). In contrast, other clinical lubricants (E-Z Lubricating Jelly, McKesson Lubricating) and personal lubricants (Astroglide Liquid, Good Clean Love Almost Naked, K-Y Warming Jelly) did not exhibit this effect. Chlorhexidine gluconate had a detrimental effect on Lactobacillus growth and exhibited stronger antimicrobial activity compared with methylparaben and propylparaben (P < 0.0001). There were lubricants that did not induce cytotoxicity in VEC (Good Clean Love Almost Naked, E-Z Lubricating Jelly, McKesson Lubricating Jelly), but these products did substantially decrease the attachment of L. crispatus to VEC, particularly when VEC were preexposed to lubricants before inoculation with bacteria (P < 0.0001). CONCLUSIONS: This in vitro model indicates that select vaginal lubricants, particularly those with chlorhexidine gluconate, have potentially adverse effects on women's health by reducing growth and recolonization of vaginal Lactobacillus species.

Microbiome engineering: engineered live biotherapeutic products for treating human disease.

The human microbiota is implicated in many disease states, including neurological disorders, cancer, and inflammatory diseases. This potentially huge impact on human health has prompted the development of microbiome engineering methods, which attempt to adapt the composition and function of the human host-microbiota system for a therapeutic purpose. One promising method is the use of engineered microorganisms that have been modified to perform a therapeutic function. The majority of these products have only been demonstrated in laboratory models; however, in recent years more concepts have reached the translational stage. This has led to an increase in the number of clinical trials, which are designed to assess the safety and efficacy of these treatments in humans. Within this review, we highlight the progress of some of these microbiome engineering clinical studies, with a focus on engineered live biotherapeutic products.