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bioRxiv · 10.1101/505115

The Salivary Microbiome: Analysis of by Pyrosequencing and the Relationship with Helicobacter pylori Infection

Ji, Y.·Liang, X.·Lu, H.
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Abstract

AbstractsO_ST_ABSBackgroundsC_ST_ABSThere have been reports of Helicobacter pylori (H. pylori) in the oral cavity and it has been suggested that the oral cavity may be a reservoir for H. pylori reflux from the stomach.\n\nObjectivesHigh-throughput pyrosequencing was used to assess the structure and composition of oral microbiota communities in individuals with or without confirmed H. pylori infection.\n\nMethodsSaliva samples were obtained from 34 H. pylori infected and 24 H. pylori uninfected subjects. Bacterial genomic DNA was extracted and examined by pyrosequencing by amplification of the 16S rDNA V3-V4 hypervariable regions followed by bioinformatics analysis. Saliva sampling was repeated from 22 of the 34 H. pylori infected subjects 2 months after H. pylori eradication.\n\nResultsHigh-quality sequences (2,812,659) clustered into 95,812 operational taxonomic units (OTUs; 97% identity), representing 440 independent species belonging to 138 genera, 68 families, 36 orders, 21 classes, and 11 phyla. Species richness (alpha diversity) of H. pylori infected subjects was similar to that of uninfected subjects. Eradication treatment decreased saliva bacterial diversity. Beta diversity analysis showed that the salivary microbial community structure differed between H. pylori infected and uninfected subjects both before and after H. pylori eradication.\n\nConclusionsSalivary microbiota diversity was similar in H. pylori infected and uninfected individuals. Antibiotic therapy was associated with a decline in salivary bacterial diversity. Both H. pylori infection and its eradication caused the oral microbiota alterations in community and structure. The present of H. pylori in oral cavity was not related with its infection status in stomach.\n\nTrial registrationClinicalTrials.gov, Identifier: NCT03730766\n\nImportanceThe oral cavity plays a vital role in Helicobacter pylori transmission among human. High-throughput pyrosequencing of the 16S rDNA V3-V4 hypervariable regions was used to assess the structure and composition of oral microbiota communities in individuals with or without confirmed Helicobacter pylori infection. We show that both Helicobacter pylori infection and eradication cause microbiota alterations in the oral microbiota. Prior studies report detection of Helicobacter pylori in the oral cavity by polymerase chain reaction. We show that the presence of Helicobacter pylori in the oral cavity is unrelated with its infection status in the stomach.

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Ji, Y., Liang, X., Lu, H.. 2018-12-25. The Salivary Microbiome: Analysis of by Pyrosequencing and the Relationship with Helicobacter pylori Infection. https://doi.org/10.1101/505115

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