The Effects of Infection on Microbiota Associated With Gastric Mucosa and Immune Factors in Children.

Background: infection is the main cause of chronic gastritis in children. Little is known about the effect of on microbiota and immunity. This study was aimed at characterizing stomach microbiota and immune-regulatory properties of children with colonization.

Methods: We studied 122 children who had undergone gastric endoscopy due to gastrointestinal symptoms, 57 were diagnosed with infection. Endoscopic mucosal biopsy samples were obtained for DNA and RNA extraction. Microbiomes were analyzed by 16S rRNA profiling, with the differentially expressed genes analyzed using RNA sequencing. The RNA-sequencing results of selected genes were validated by qRT-PCR.

Results: Bacterial diversity of -positive gastric specimens were lower than those of negative, and both groups were clearly separated according to beta diversity. -positive group significantly reduced proportions of six phyla and eight genera; only taxa were more abundant in negative group. Gastric tissues RNA sequencing showed increased expression of multiple immune response genes in -infection. -infected children with restructured gastric microbiota had higher levels of FOXP3, IL-10, TGF-β1 and IL-17A expressions, which were consistent with increased CD4T cell and macrophagocyte, compared with non-infected children.

Conclusions: Presence of significantly influences gastric microbiota and results in lower abundance of multiple taxonomic levels in children. Meanwhile, it affects gastric immune environment and promotes the occurrence of gastritis.

Clinical Trial Registration: [http://www.chictr.org.cn], identifier [ChiCTR1800015190].