Microbial Characterization of Endometriosis

Summary:A signature that unifies the Endometriosis (EM) microbiota across multiple body sites has not been identified. Herein, we enrolled 41 women (non-EM, n=20; EM, n=21) and collected 122 well-matched samples, derived from feces, cervical mucus and peritoneal fluid, and demonstrated the nature of microbiome in endometriosis. Microbial composition is remarkably distinguished between three body sites, with 19 overlapped taxa. Moreover, endometriosis patients harbour distinct microbial communities versus non-endometriosis especially in feces and peritoneal fluid, with increased abundance of pathogens in peritoneal fluid and depletion of protective microbes in feces. In particular, genera Ruminococcus and Pseudomonas were identified as potential biomarkers, to be specific, Lachnospiraceae Ruminococcus was depleted in gut, whereas Pseudomonadaceae Pseudomonas was over-represented in the peritoneal cavity among endometriosis individuals. Despite the high interpersonal and intrapersonal variation of microbiota, the microbial network shown a co-occurrence relationship between L. Ruminococcus and P. Pseudomonas. Furthermore, novel endometriosis classifiers were constructed based on taxa selected by a robust machine learning method. Collectively, this study reveals important insights into the microbial profiling in different body sites of non-endometriosis and endometriosis, which warrant future exploration into the role of microbiota in endometriosis and highlighted values on the etiopathology of endometriosis.IMPORTANCE:Endometriosis is a type of chronic inflammatory gynecological disease, mainly took place in peritoneal cavity. In order to investigate the possible correlation between microbes and endometriosis, we performed 16S rDNA amplicon sequencing of 122 paired samples derived from feces, cervical mucus and peritoneal fluid. We found that women with endometriosis harbor distinct microbial communities versus non-endometriosis, with increased abundance of pathogens in peritoneal cavity and depletion of protective microbes in gut. In particular, the presence of Pseudomonadaceae Pseudomonas may be a potential risk factor in peritoneal cavity, and the depletion of Lachnospiraceae Ruminococcus in gut might be a biomarker for endometriosis. These observations may provide a clue for future investigation in elucidating pathophysiology of endometriosis.