Unraveling the role of the secretor antigen in human rotavirus attachment to histo-blood group antigens

25 Páginas, 7 figuras, 2 tablas

Different transmission patterns of uncommon group A human rotavirus genotypes

Epidemiological Surveillance of Norovirus and Rotavirus in Sewage (2016–2017) in Valencia (Spain)

© 2020 by the authors.

Recombinant Noroviruses Circulating in Spain from 2016 to 2020 and Proposal of Two Novel Genotypes within Genogroup I.

Noroviruses are the leading cause of sporadic cases and outbreaks of viral gastroenteritis. For more than 20 years, most norovirus infections have been caused by the pandemic genotype GII.4, yet recent studies have reported the emergence of recombinant strains in many countries. In the present study, 4,950 stool samples collected between January 2016 and April 2020 in Valencia, Spain, from patients with acute gastroenteritis were analyzed to investigate the etiological agent. Norovirus was the most frequently detected enteric virus, with a positivity rate of 9.5% (471/4,950). Among 224 norovirus strains characterized, 175 belonged to genogroup II (GII) and 49 belonged to GI. Using dual geno…

Nearly Complete Genome Sequence of a Human Norovirus GII.P17-GII.17 Strain Isolated from Brazil in 2015

Human noroviruses are the most common cause of nonbacterial acute gastroenteritis worldwide. We report here the nearly complete genome sequence (7,551 nucleotides) of a human norovirus GII.P17-GII.17 strain detected in July 2015 in the stool sample from an adult with acute gastroenteritis in Brazil.

Microbiota Depletion Promotes Human Rotavirus Replication in an Adult Mouse Model

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…

Evaluation of VIASURE real-time PCR assays for detection of rotavirus and norovirus GI and GII in fecal samples

Nearly Complete Genome Sequences of Human Norovirus Belonging to Several Genotypes from Valencia, Spain

Human noroviruses are responsible for most nonbacterial acute gastroenteritis cases. The GII.2, GII.4, and GII.17 genotypes of human noroviruses have recently arisen as the most frequent genotypes found in humans worldwide. We report here seven nearly complete genomes of these genotypes from patients with acute gastroenteritis in Valencia, Spain.

Histo-blood group antigens in children with symptomatic rotavirus infection

Group A rotaviruses are a major cause of acute gastroenteritis in children. The diversity and unequal geographical prevalence of rotavirus genotypes have been linked to histo-blood group antigens (HBGAs) in different human populations. In order to evaluate the role of HBGAs in rotavirus infections in our population, secretor status (FUT2+), ABO blood group, and Lewis antigens were determined in children attended for rotavirus gastroenteritis in Valencia, Spain. During three consecutive years (2013&ndash

Relevance of secretor status genotype and microbiota composition in susceptibility to rotavirus and norovirus infections in humans

Host genetic factors, such as histo-blood group antigens (HBGAs), are associated with susceptibility to norovirus (NoV) and rotavirus (RV) infections. Recent advances point to the gut microbiome as a key player necessary for a viral pathogen to cause infection. In vitro NoV attachment to host cells and resulting infections have been linked to interactions with certain bacterial types in the gut microbiota. We investigated the relationship between host genotype, gut microbiota, and viral infections. Saliva and fecal samples from 35 adult volunteers were analysed for secretor status genotype, the gut microbiota composition by 16S rRNA gene sequencing, and salivary IgA titers to NoV and RV. Hi…

Characterization of a Novel Conformational GII.4 Norovirus Epitope: Implications for Norovirus-Host Interactions

ABSTRACT Human noroviruses (NoVs) are the main etiological agents of acute gastroenteritis worldwide. While NoVs are highly diverse (more than 30 genotypes have been detected in humans), during the last 40 years most outbreaks and epidemics have been caused by GII.4 genotype strains, raising questions about their persistence in the population. Among other potential explanations, immune evasion is considered to be a main driver of their success. In order to study antibody recognition and evasion in detail, we analyzed a conformational epitope recognized by a monoclonal antibody (3C3G3) by phage display, site-directed mutagenesis, and surface plasmon resonance. Our results show that the predi…

Epidemiological and Genetic Characterization of Sapovirus in Patients with Acute Gastroenteritis in Valencia (Spain)

Sapovirus is a common cause of acute gastroenteritis in all age groups. Sapovirus infections are seldom investigated in Spain, and its epidemiology in the country is not well known. The use of molecular diagnostic procedures has allowed a more frequent detection of sapoviruses in patients with diarrhea. A total of 2545 stool samples from patients with acute gastroenteritis attended from June 2018 to February 2020 at the Clinic University Hospital in Valencia, Spain, were analyzed by reverse transcription (RT) and real-time multiplex PCR (RT-PCR) to investigate the etiology of enteric infections. Sapovirus was the second enteric virus detected with a positive rate of 8%, behind norovirus (12…

Phylogenetic analysis of G12 group A rotavirus circulating in Spain during 2012–2015: Detection of different clusters with distinct evolutionary origins

Characterisation of a household norovirus outbreak occurred in Valencia (Spain)

Background Human noroviruses (NoVs) are the main cause of non-bacterial gastroenteritis worldwide. Several studies have linked human susceptibility to NoVs with the expression of histo-blood group antigens (HBGAs). In January 2012, a NoV gastroenteritis outbreak affected a household in Valencia, Spain, and the personal susceptibility to NoV was investigated. Methods To reach this aim 8 members of the affected household were recruited for this study and their secretor status, ABO and Lewis antigens were determined. NoV-specific saliva IgA and serum IgG antibody titers were analyzed. Their capacity to block viral binding to saliva receptors was analyzed, using virus-like particles (VLPs) of t…

Interaction of Intestinal Bacteria with Human Rotavirus during Infection in Children

The gut microbiota has emerged as a key factor in the pathogenesis of intestinal viruses, including enteroviruses, noroviruses and rotaviruses (RVs), where stimulatory and inhibitory effects on infectivity have been reported. With the aim of determining whether members of the microbiota interact with RVs during infection, a combination of anti-RV antibody labeling, fluorescence-activated cell sorting and 16S rRNA amplicon sequencing was used to characterize the interaction between specific bacteria and RV in stool samples of children suffering from diarrhea produced by G1P[8] RV. The genera Ruminococcus and Oxalobacter were identified as RV binders in stools, displaying enrichments between …