Search results for "HBGA"
showing 8 items of 8 documents
The interactions between host glycobiology, bacterial microbiota, and viruses in the gut
2018
Rotavirus (RV) and norovirus (NoV) are the major etiological agents of viral acute gastroenteritis worldwide. Host genetic factors, the histo-blood group antigens (HBGA), are associated with RV and NoV susceptibility and recent findings additionally point to HBGA as a factor modulating the intestinal microbial composition. In vitro and in vivo experiments in animal models established that the microbiota enhances RV and NoV infection, uncovering a triangular interplay between RV and NoV, host glycobiology, and the intestinal microbiota that ultimately influences viral infectivity. Studies on the microbiota composition in individuals displaying different RV and NoV susceptibilities allowed th…
Molecular analysis of enteric viruses circulating in Tunisia : relationships between blood group antigens and rotavirus and norovirus infectivity
2015
Rotavirus and norovirus are the main aetiological agents of gastroenteritis in Tunisia. Stool specimens and saliva were collected from children younger than 6 years of age, admitted to the Fattouma Bourguiba Hospital (Monastir, Tunisia) for gastroenteritis during the winter 2011-12. Saliva analysis showed that 79% and 21% patients had secretor and non-secretor phenotypes, respectively. Group O blood type was predominant (42%) followed by groups A (30%), B (21%) and AB (7%), whilst 96% of the patients were positive for Lewis antigen. For 98 patients, blood samples were available and were used for FUT2 genotyping. 77.6% of the cohort were secretor (Se+/Se+ and Se+/se-) and 22.4% were non-secr…
Antibodies against Lewis antigens inhibit the binding of human norovirus GII.4 virus-like particles to saliva but not to intestinal Caco-2 cells.
2016
BACKGROUND: Human noroviruses (NoVs) are the main cause of gastroenteritis worldwide. The most commonly detected NoV strains belong to the genetically diverse GII.4 genotype, with new pandemic variants emerging periodically. Despite extensive efforts, NoV investigation has been hampered by the lack of an effective in vitro cell culture system. However, NoV-derived recombinant virus-like particles (VLPs) resembling empty capsids are good surrogates for analysing NoV antigenicity and virus-ligand interactions. NoV VLPs have been reported to bind to histo-blood group antigens (HBGAs). We have analysed the ability of NoV VLPs derived from GI.1 genotype and from three GII.4 genotype variants, GI…
Histo-blood group antigens in children with symptomatic rotavirus infection
2019
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
Specific norovirus interaction with Lewis x and Lewis a on human intestinal inflammatory mucosa during refractory inflammatory bowel disease
2021
Inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), are progressive diseases affecting millions of people each year. Flare-ups during IBD result in severe mucosal alterations of the small intestine (in CD) and in the colon and rectum (in CD and UC).
Norovirus-Host Interactions in the course of Inflammatory Bowel Disease
2021
Inflammatory bowel disease (IBD) affects around 200,000 people in France. This group of conditions includes Crohn's disease (CD), which involves the entire digestive tract, and ulcerative colitis (UC), which involves only the colon and rectum. It is known that immunological, genetic and microbiological factors are at play in IBD, but the role of viruses remains only partially explored. Among viral etiologies, human noroviruses (huNoV) are the main cause of acute viral gastroenteritis worldwide. Norovirus binds to intestinal cells through histo-blood group antigens (HBGA), including ABO and Lewis antigens. The expression of HBGA is dependent upon tissue type and the underlying physiopatholog…
Estudi de la immunogenicitat de Norovirus humans i de la seua interacció amb receptors cel·lulars
2014
Noroviruses (NoVs) are the main cause of sporadic cases and outbreaks of acute gastroenteritis (Tam et al., 2012; Gastanaduy et al., 2013) and are globally associated with a large burden of disease (Patel et al., 2008). NoVs are a highly diverse group of viruses, although over the past two decades most reported NoV outbreaks and epidemics have been caused by NoV GII.4 genotype. Phylogenetic analyses of the GII.4 strains circulating in the last 20 years have shown that this genotype can be divided into distinct variants, which peak and wane over time in a similar pattern to that described for influenza viruses (Buesa et al., 2008; Siebenga et al., 2009; Koelle et al., 2006). In recent years …
Rôle des antigènes tissulaires de groupes sanguins humains A, B, H et Lewis dans l'évolution des Norovirus GII.4
2011
Noroviruses are one of the leading causes of gastroenteritis worldwide. Since 2002 successive GII.4 variants have circulated in the population before being replaced every 2-3 years, which raises questions about the role of their histo-blood group antigen (HBGAs) receptors in their evolution. We analyzed the interaction between representative GII.4 variants and HBGAs and determined the role of selected amino acids (aa) in the binding profiles. By mutagenesis, we showed that there was a strict structural requirement for the aa directly implicated in HBGA bindings. The ablation of the threonine 395 residue, an epidemiological feature of the post 2002 variants, allowed to gain the capacity to b…