Microbiota Depletion Promotes Human Rotavirus Replication in an Adult Mouse Model

Abstract

Intestinal microbiota-virus-host interaction has emerged as a key factor in mediating enteric virus pathogenicity. With the aim of analyzing whether human gut bacteria improve the inefficient replication of human rotavirus in mice, we performed fecal microbiota transplant (FMT) with healthy infants as donors in antibiotic-treated mice. We showed that a simple antibiotic treatment, irrespective of FMT, resulted in viral shedding for 6 days after challenge with the human rotavirus G1P[8] genotype Wa strain (RVwa). Rotavirus titers in feces were also significantly higher in antibiotic-treated animals with or without FMT but they were decreased in animals subject to self-FMT, where a partial re-establishment of specific bacterial taxons was evidenced. Microbial composition analysis revealed profound changes in the intestinal microbiota of antibiotic-treated animals, whereas some bacterial groups, including members of Lactobacillus, Bilophila, Mucispirillum, and Oscillospira, recovered after self-FMT. In antibiotic-treated and FMT animals where the virus replicated more efficiently, differences were observed in gene expression of immune mediators, such as IL1β and CXCL15, as well as in the fucosyltransferase FUT2, responsible for H-type antigen synthesis in the small intestine. Collectively, our results suggest that antibiotic-induced microbiota depletion eradicates the microbial taxa that restrict human rotavirus infectivity in mice. ; This research was funded by Spanish Government (Ministerio de Economía y Competitividad) grants AGL2017-84165-C2-1-R to MJY, AGL2017-84165-C2-2-R to JRD. The study was also supported by Valencian Government grant IDIFEDER/2018/056 and by European FEDER founds. RGR is the recipient of a postdoctoral grant from the Valencian Government (APOST/2017/037). CSB is the recipient of a FPI predoctoral grant from the Spanish Government (RE2018-083315). SVV is the recipient of a predoctoral grant from the Valencian Government (ACIF/2016/437). ; Peer reviewed