Comparison of viromes in vaginal secretion from pregnant women with and without vaginitis

He-Teng Zhang,Hao Wang,Jian Zeng,Yan Yang,Hai-Sheng Wu

doi:10.1186/s12985-020-01482-z

Abstract

BackgroundAlthough some studies have investigated the bacterial community in vaginal tract of pregnant women, there are few reports about the viral community (virome) in this type of microenvironment.MethodsTo investigate the composition of virome in vaginal secretion samples, 40 vaginal secretion samples from pregnant women with vaginitis and 20 vaginal secretion samples from pregnant women without vaginitis, pooled into 4 and 2 sample pools, respectively, were subjected to viral metagenomic analysis.ResultsResults indicated virus sequences showing similarity to human papillomavirus (HPV), anellovirus, and norovirus were recovered from this cohort of pregnant women. Further analysis indicated that 15 different defined types and one unclassified type of HPV were detected from pregnant women with vaginitis while only 3 defined types of HPV were detected in pregnant women without vaginitis. Five different groups of viruses from the family Anelloviridae were present in pregnant women with but none of them were detected in pregnant women without vaginitis. Norovirus was detected in 3 out of the 4 sample pools from pregnant women with vaginitis but none in the pregnant women without vaginitis. Twelve complete genomes belonging to 10 different types of HPV, and 5 novel anllovirus genomes belonging 2 different genera in Anelloviridae were acquired from these libraries, based on which phylogenetical analysis and pairwise sequence comparison were performed. Phageome in these samples was also briefly characterized and compared between two groups.ConclusionOur data suggested that virome might play an important role in the progression of vaginitis in pregnant women.

Highlights

Vaginal microecology is a dynamic balance state of mutual restriction and coordination composed of vaginal microorganisms, normal vaginal anatomy, periodic endocrine changes and local vaginal immune system
A total of 15 different defined and one unclassified human papillomavirus (HPV) types were detected in the samples from the vaginitis group, while only 3 type of HPV were recovered from the samples from non-vaginitis group
Apart from HPV, a large number of anellovirus sequences were detected in the 4 libraries from pregnant women with vaginitis but in none of the libraries from pregnant women without vaginitis

Summary

Introduction

Vaginal microecology is a dynamic balance state of mutual restriction and coordination composed of vaginal microorganisms, normal vaginal anatomy, periodic endocrine changes and local vaginal immune system. Viral infections are common in vagina and cervix of healthy, asymptomatic women. Many viral pathogens are known to be important components of the vaginal microbiome, viruses have been less studied than bacteria. Two recent reports have investigated the vaginal virome to analyze the link between phageome and bacterial vaginitis [9] and the link between eukaryotic DNA virome and preterm birth [10]. The two studies both only investigated the DNA virus in vagina. Using viral metagenomics, were investigated and compared the viromes (including eukaryotic virome and phageome) between pregnant women without vaginitis and these with vaginitis. Some studies have investigated the bacterial community in vaginal tract of pregnant women, there are few reports about the viral community (virome) in this type of microenvironment

Methods

Results

Discussion

Conclusion