The Cervicovaginal Microbiome Can Elicit Resistance To The Chlamydia

The study showing that how the cervicovaginal microbiome can elicit resistance to the chlamydia; vaginal microbiome is believing to protect women against Chlamydia trachomatis; the etiological agent of the most prevalent sexually transmitted infections in developing countries. New research by the University of Maryland School of Medicine showing how the microbiome can either protect or make a woman more susceptible to these serious infections.

Chlamydia is a major growing health issue in the U.S., and more work is needed to understand why some women are apparently naturally protected while other are not. Our novel research aims to decipher the mechanistic and functional underpinnings of communication between the host and the cervicovaginal microbiome to better understand resistance and susceptibility to this infection.

Resistance to the chlamydia

While Lactobacillus-dominated microbiota in a woman’s vagina has long been suspected to provide a protective barrier against STIs like chlamydia, investigators at IGS and the University of Maryland School of Dentistry (UMSOD) are reporting for the first time a mechanism enabling specific types of cervicovaginal microbiome to predispose cells in the vagina and cervix to resist chlamydial infection.

But leverage of these microbiomes to identify women at risk of infections; but more importantly to develop improved strategies to restore an optimal protection when it is lacking. Unlike our genes, the vaginal microbiome can be modulating to increase protection against chlamydia; but also against other sexually transmitted infections, including HIV. The research is important amid a rising number of cases of chlamydia worldwide. In the U.S. alone, 1.7 million cases of chlamydia were reporting in 2017; a 22% increase since 2013, according to data from the Centers for Diseases Control and Prevention.

Human cells against chlamydial infection

But the current research showed that Lactobacillus iners; a bacterium actually commonly found in the vagina did not optimally protect human cells against chlamydial infection; while products of Lactobacillus crispatus, another Lactobacillus species frequently found in the vagina. The researchers finding that the D-lactic acid; not L-lactic acid, down regulates cell cycling through epigenetic modifications thus blocking C. trachomatis entry into the cell, one of the pathogen key infectious process, among other processes.

The vaginal microbiome does not affect the pathogen per se, but drives susceptibility or resistance to infection; by modifying the cells that line up the cervicovaginal epithelium. The researchers further demonstrating that exposure to optimal vaginal microbiota provided long term protection; which has major implication on how a woman is protected. These mechanisms are now being exploiting to develop strategies to optimize protection against C. trachomatis infections but also other STIs.