VP4 Is a Determinant of Alpha-Defensin Modulation of Rotaviral Infection.

Fecal-oral pathogens encounter constitutively expressed enteric alpha-defensins in the intestine during replication and transmission. Alpha-defensins can be potently antiviral and antibacterial; however, their primary sequences, the number of isoforms, and their activity against specific microorganisms often vary greatly between species, reflecting adaptation to species-specific pathogens. Therefore, alpha-defensins might influence not only microbial evolution and tissue tropism within a host but also species tropism and zoonotic potential. To investigate these concepts, we generated a panel of enteric and myeloid alpha-defensins from humans, rhesus macaques, and mice and tested their activity against group A rotaviruses, an important enteric viral pathogen of humans and animals. Rotaviral adaptation to the rhesus macaque correlated with resistance to rhesus enteric, but not myeloid, alpha-defensins and sensitivity to human alpha-defensins. While mouse rotaviral infection was increased in the presence of mouse enteric alpha-defensins, two prominent genotypes of human rotaviruses were differentially sensitive to human enteric alpha-defensins. Furthermore, the effects of cross-species alpha-defensins on human and mouse rotaviruses did not follow an obvious pattern. Thus, exposure to alpha-defensins may have shaped the evolution of some, but not all, rotaviruses. We then used a genetic approach to identify the viral attachment and penetration protein, VP4, as a determinant of alpha-defensin sensitivity. Our results provide a foundation for future studies of the VP4-dependent mechanism of defensin neutralization, highlight the species-specific activities of alpha-defensins, and focus future efforts on a broader range of rotaviruses that differ in VP4 to uncover the potential for enteric alpha-defensins to influence species tropism. IMPORTANCE Rotavirus is a leading cause of severe diarrhea in young children. Like other fecal-oral pathogens, rotaviruses encounter abundant, constitutively expressed defensins in the small intestine. These peptides are a vital part of the vertebrate innate immune system. By investigating the impact that defensins from multiple species have on the infectivity of different strains of rotavirus, we show that some rotaviral infections can be inhibited by defensins. We also found that some, but not all, rotaviruses may have evolved resistance to defensins in the intestine of their host species, and some even appropriate defensins to increase their infectivity. Because rotaviruses infect a broad range of animals and rotaviral infections are highly prevalent in children, identifying immune defenses against infection and how they vary across species and among viral genotypes is important for our understanding of the evolution, transmission, and zoonotic potential of these viruses as well as the improvement of vaccines.

Clinical and molecular epidemiological characterization of rotavirus infections in children under five years old in Shandong province, China.

Rotaviruses are important causative agents of acute gastroenteritis in children. In China, rotavirus infection has a prevalence rate of 30% and is therefore considered a serious public health problem. This study was carried out to investigate the clinical and molecular epidemiological characteristics of rotavirus infections in children under 5 years old with acute diarrhea in Shandong province, China. From July 2017 to June 2018, a total of 1211 fecal specimens were tested, and the prevalence of rotavirus infection was 32.12%. The mean age of the infected children was 12.2 ± 10.9 months, and the highest infection rate was observed in children aged 7-12 months, with a rate of 41.64%. G9P[8] (76.61%) was the most prevalent genotype combination, followed by G2P[4] (7.20%), G3P[8] (3.60%), and G9P[4] (2.06%). In addition to diarrhea, vomiting, fever, and dehydration were the most common clinical signs. In general, there was no significant difference in clinical manifestations among different age groups. However, the clinical manifestations differed significantly between vaccinated and unvaccinated children. Vaccinated children showed lower incidence and frequency of vomiting, lower incidence and degree of dehydration, and lower incidence of severe cases than unvaccinated children. These findings suggest that it is necessary to continuously monitor changes in the characteristics of rotavirus infections. Moreover, the introduction of vaccines into the national immunization program to prevent and control rotavirus infection is needed in China.

The effect of Cryptosporidiumparvum, rotavirus, and coronavirus infection on the health and performance of male dairy calves.

The objective of this prospective cohort study was to investigate the effect of bovine coronavirus (BCoV), bovine rotavirus (BRoV), and Cryptosporidiumparvum on dairy calf health and performance and to determine the prevalence of these pathogens. A total of 198 male dairy calves housed at a grain-fed veal facility were examined from June 11, 2018, to October 9, 2018. Calves were fed milk replacer twice daily and housed individually until weaning at 56 d. Once weaned, calves were moved into groups of 5 until they were moved to a finishing facility at 77 d. At the grain-fed veal facility, calves were scored for fecal consistency for the first 28 d and had fecal samples taken on arrival and at 7 and 14 d. Fecal samples were frozen and submitted to a commercial laboratory, where they were tested for BCoV, C.parvum, and 2 groups of BRoV: group A (BRoV A) and group B (BRoV B). Calves were weighed on arrival and at 14, 49, 56, and 77 d using a digital body scale. Treatments for disease and mortalities that occurred over the 77 d were also recorded. Statistical models, including Cox proportional hazards and repeated measures models, were built to determine the effect of infection with 1 of the pathogens. Over the 3 sampling points, 151 (85.8%), 178 (94.2%), 3 (1.5%), and 97 (57.4%) calves tested positive at least once for BCoV, BRoV A, BRoV B, and C.parvum, respectively. The source of the calves and the level of serum total protein measured on arrival were associated with testing positive for a pathogen. Calves that tested positive for C.parvum had an increased proportion of days with diarrhea and severe diarrhea; calves that tested positive for BCoV and BRoV A had an increased proportion of days with severe diarrhea. In addition, calves that tested positive for C.parvum had a higher hazard of being treated for respiratory disease. With respect to body weight, calves that had diarrhea or severe diarrhea had lower body weight at 49, 56, and 77 d. Specifically, calves that had an increased proportion of days with diarrhea showed a reduction in weight gain of up to 15 kg compared to calves without diarrhea. Calves that tested positive for C.parvum had a lower body weight at 49, 56, and 77 d; calves that tested positive for BCoV had a lower body weight at 56 and 77 d. This study demonstrates that the prevalence of BCoV, BRoV A, and C.parvum infection is high in this population of calves and has significant effects on the occurrence of diarrhea and body weight gain. Future studies should evaluate approaches for minimizing the effect of infection with these pathogens to improve the welfare, health, and productivity of dairy calves.

[A child with inexplicable alteration of consciousness]. / Een kleuter met onbegrepen gedaald bewustzijn.

A 4-year-old girl presented with an alteration of consciousness and absence of speech after a short period of vomiting, diarrhoea and fever. MRI of the brain revealed a focal lesion in the splenium of the corpus callosum. Rotavirus was detected in the faeces. We concluded that the rotavirus infection had caused mild encephalopathy with a reversible splenial lesion.

Postvaccination Serum Antirotavirus Immunoglobulin A as a Correlate of Protection Against Rotavirus Gastroenteritis Across Settings.

BACKGROUND: A correlate of protection for rotavirus gastroenteritis would facilitate rapid assessment of vaccination strategies and the next generation of rotavirus vaccines. We aimed to quantify a threshold of postvaccine serum antirotavirus immunoglobulin A (IgA) as an individual-level immune correlate of protection against rotavirus gastroenteritis. METHODS: Individual-level data on 5074 infants in 9 GlaxoSmithKline Rotarix Phase 2/3 clinical trials from 16 countries were pooled. Cox proportional hazard models were fit to estimate hazard ratios (HRs) describing the relationship between IgA thresholds and occurrence of rotavirus gastroenteritis. RESULTS: Seroconversion (IgA ≥ 20 U/mL) conferred substantial protection against any and severe rotavirus gastroenteritis to age 1 year. In low child mortality settings, seroconversion provided near perfect protection against severe rotavirus gastroenteritis (HR, 0.04; 95% confidence interval [CI], .01-.31). In high child mortality settings, seroconversion dramatically reduced the risk of severe rotavirus gastroenteritis (HR, 0.46; 95% CI, .25-.86). As IgA threshold increased, risk of rotavirus gastroenteritis generally decreased. A given IgA threshold provided better protection in low compared to high child mortality settings. DISCUSSION: Postvaccination antirotavirus IgA is a valuable correlate of protection against rotavirus gastroenteritis to age 1 year. Seroconversion provides an informative threshold for assessing rotavirus vaccine performance.

Rotavirus gastroenteritis among hospitalized children under 5 years of age in the Eastern Mediterranean Region: a review.

BACKGROUND: Rotavirus(RV) is one of the primary causes globally of acute diarrhoea in children below 5 years of age. AIMS: This literature research aims to evaluate the rotavirus diarrhoea among hospitalized children < 5 years of age in the Eastern Mediterranean Region from 2010 to 2016. Data from each country were extracted and compared. METHODS: An extensive literature search was carried out using the following databases: PubMed, Google Scholar and Science Direct, with the keyword "Rotavirus". The search was limited to articles published from January 2010 to December 2016. RESULTS: The search identified 28 studies. Rotavirus gastroenteritis (RVGE) identification in studies countries ranged from from 19%-78.2% of all tested diarrhoeal specimens, primarily in children ≤ 1 year of age. RV occurred throughout the year, with peak incidence during autumn and winter seasons. G1P[8] was the predominant circulating genotype combination followed by G9P[8] and G2P[4]. Out of 28 studies, only one examined the economic burden which ranged from US$ 245 to $345 per hospitalized child due to RV diarrhoea. Moreover, three days were the minimum duration of hospitalization. No available data on the mortality rates due to RVGE among the selected studies. CONCLUSIONS: This research documents that RV is one of the most significant pathogens that cause morbidity and mortality in the paediatric population in Eastern Mediterranean Region countries. The data from this literature research may help public healthcare workers in decreasing mortality and morbidity resulting from RVGE in the region.

Rotavirus Gastroenteritis Associated with Encephalopathy, Myositis, Transaminitis and Hypoalbuminemia.

Rotavirus is a common cause of acute gastroenteritis in children. Manifestations of rotavirus gastroenteritis beyond gastrointestinal tract are rare. Rotavirus has been reported to be associated with encephalopathy, myositis and elevated liver enzymes; but simultaneous presentation of all these conditions in the same child is extremely rare. The authors report a case of 17-mo-old girl who presented with acute rotavirus gastroenteritis with G3 + G9P[8] strain associated with hypernatremia, encephalopathy, myositis, transaminitis and hypoalbuminemia. Child had complete recovery with no neurological sequalae on follow-up, and liver enzymes and albumin returned to normal. The authors suggest that rotavirus infection should be considered in the differential diagnosis of a child with encephalopathy or myositis, particularly if associated with acute diarrhea.

Talk to Patients About: Rotavirus.

Rotavirus is a highly contagious viral infection that inflames the lining of the stomach and intestines, and especially affects children 2 years old and younger. In the United States, the introduction of a vaccine in 2006 helped arrest rotavirus illnesses and deaths.

Incidence and characteristics of norovirus-associated benign convulsions with mild gastroenteritis, in comparison with rotavirus ones.

BACKGROUND AND PURPOSE: Rotavirus was detected in 40-50% of patients with benign convulsions with mild gastroenteritis (CwG) before the rotavirus vaccine was introduced in late 2000. However, the rate of rotavirus positivity has decreased since 2010 while the prevalence of norovirus has gradually increased. We investigated the incidence of norovirus-associated CwG during a recent 3-year period and additionally compared the characteristics of norovirus-associated CwG with those of rotavirus-associated CwG. METHODS: The medical records of CwG patients admitted to our hospital between March 2014 and February 2017 were reviewed, including the results of stool virus tests. For comparing norovirus- and rotavirus-associated CwG, data obtained between March 2005 and February 2014 that included sufficient numbers of patients with rotavirus-associated CwG were additionally reviewed. Data were collected on clinical characteristics (age, sex, seasonal distribution, enteric symptoms, and the interval to seizure onset), seizure characteristics (frequency, duration, type, and electroencephalographic findings), and laboratory findings. RESULTS: CwG was diagnosed in 42 patients during the 3-year study period. Stool viruses were checked in 40 (95.2%) patients and were detected in 32 (80.0%) patients. Norovirus genogroup II was detected in 27 (67.5%) of the 40 patients, rotavirus was detected in 3 patients, and adenovirus was detected in 2 patients. In total, 140 CwG patients were enrolled between March 2005 and February 2017. The patients with norovirus-associated CwG (N = 44) and rotavirus-associated CwG (N = 26) were aged 18.66 ±â€¯5.57 and 19.31 ±â€¯7.37 months (mean ±â€¯standard deviation), respectively (P > 0.05). Norovirus-associated CwG was less prevalent than rotavirus-associated CwG during spring (13.6% vs. 34.6%, P = 0.04), while the prevalence of both types of CwG peaked during winter (63.6% and 46.2%, respectively). Vomiting was more prevalent in norovirus- than rotavirus-associated CwG (97.7% vs. 80.8%, P = 0.02) and the interval between enteric symptom onset and seizure onset was shorter in norovirus-associated CwG (2.00 ±â€¯1.06 vs. 2.58 ±â€¯1.21 days, P = 0.04). Most cases in both groups had seizures that lasted for less than 5 min (95.5% vs. 92.3%). Clustered seizures seemed to occur more frequently in the norovirus group (79.5% vs. 57.7%), although with borderline significance (P = 0.05). Posterior slowing was observed more frequently in norovirus-associated CwG (34.9% vs. 11.5%, P = 0.03). CONCLUSION: The most common viral pathogen of CwG was norovirus during the analyzed 3-year period, with an incidence of 67.5%. In comparison with rotavirus-associated CwG, norovirus-associated CwG was less frequent during spring, more frequently seen with vomiting, had a shorter interval from enteric symptom onset to seizure onset, and more frequently showed posterior slowing in electroencephalography.

Clinical Findings and Neurologic Outcome in Neonatal Encephalopathy With White Matter Injury Accompanied by Rotavirus.

Our objective was to elucidate the clinical characteristics and neurodevelopmental outcomes in neonatal encephalopathy with characteristic white matter injury as compared with other injury patterns on magnetic resonance diffusion-weighted imaging. We conducted a retrospective study comparing clinical and laboratory findings, and neurologic outcomes between 17 newborns with diffuse lesions in the periventricular white matter and white matter tract (group I) and 22 newborns with other patterns (group II). Stool samples indicated that 16 neonates (94.1%) in group I were rotavirus-positive, whereas none in group II had rotavirus infection. Significantly lower calcium levels were found in group I than in group II ( P < .001). Moreover, a more favorable neurodevelopmental outcome was observed in group I than in group II. This study suggests that characteristic white matter injury in neonatal encephalopathy may be related to decreased calcium levels induced by rotavirus, and may have a better neurodevelopmental prognosis than other causes.

Analysis of structure-function relationship in porcine rotavirus A enterotoxin gene.

Rotavirus (RV)-infected piglets are presumed to be latent sources of heterologous RV infection in humans and other animals. In RVs, non-structural protein 4 (NSP4) is the major virulence factor with pleiotropic properties. In this study, we analyzed the nsp4 gene from porcine RVs isolated from diarrheic and non-diarrheic cases at different levels of protein folding to explore correlations to diarrhea-inducing capabilities and evolution of nsp4 in the porcine population. Full-length nsp4 genes were amplified, cloned, sequenced, and then analyzed for antigenic epitopes, RotaC classification, homology, genetic relationship, modeling of NSP4 protein, and prediction of post-translational modification. RV presence was observed in both diarrheic and non-diarrheic piglets. All nsp4 genes possessed the E1 genotype. Comparison of primary, secondary, and tertiary structure and the prediction of post-translational modifications of NSP4 from diarrheic and non-diarrheic piglets revealed no apparent differences. Sequence analysis indicated that nsp4 genes have a multi-phyletic evolutionary origin and exhibit species independent genetic diversity. The results emphasize the evolution of the E9 nsp4 genotype from the E1 genotype and suggest that the diarrhea-inducing capability of porcine RVs may not be exclusively linked to its enterotoxin gene.

Resveratrol dimer trans-ε-viniferin prevents rotaviral diarrhea in mice by inhibition of the intestinal calcium-activated chloride channel.

We previously identified, by a natural-product screen, resveratrol oligomers as inhibitors of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel. Here, we report the resveratrol dimer trans-ε-viniferin (TV) and tetramer r-2-viniferin (RV) as inhibitors of the intestinal calcium-activated chloride channel (CaCC) and demonstrate their antisecretory efficacy in a neonatal mouse model of rotaviral diarrhea. Short-circuit measurements show inhibition of CaCC current in the human colonic cell line HT-29 by TV and RV with IC50∼1 and 20µM, respectively. TV primarily inhibited the physiologically relevant, long-term CaCC current following agonist stimulation, without effect on cytoplasmic Ca2+ signaling. TV and RV inhibited short-circuit current in mouse colon as well. In a neonatal mouse model of rotaviral secretory diarrhea produced by oral inoculation with rotavirus, 2µg TV or 11µg RV inhibited secretory diarrhea by >50%, without effect on the rotaviral infection. Our results support the antisecretory efficacy of non-toxic, natural-product resveratrol oligomers for diarrheas produced by CaCC activation. Because these compounds also inhibit the CFTR chloride channel, they may be useful for antisecretory therapy of a wide range of diarrheas.

Norovirus and Rotavirus Disease Severity in Children: Systematic Review and Meta-analysis.

BACKGROUND: Rotaviruses (RVs) and noroviruses (NoVs) are the most common causes of severe acute gastroenteritis in children. It is generally accepted that RVs cause severe acute gastroenteritis in a higher proportion of cases compared with NoVs. To our knowledge, there are no systematic reviews and meta-analyses comparing the severity of NoV and RV disease. METHODS: We searched MEDLINE for studies reporting data for NoV and RV medically attended disease severity in children. We included studies where all children had been tested for both NoV (reverse transcription polymerase chain reaction) and RV (enzyme-linked immunosorbent assay or reverse transcription polymerase chain reaction) and that reported disease severity using the Vesikari or modified Vesikari score, or provided clinical information on severity. We generated pooled estimates of the mean with 95% confidence intervals using random effects meta-analysis. RESULTS: We identified 266 publications, of which 31 were retained for qualitative analysis and 26 for quantitative analysis. Fourteen studies provided data on severity score for the meta-analysis. The pooled mean severity scores (95% confidence interval) among outpatients were 10 (8-12) and 11 (8-14) for NoV and RV, respectively. Among inpatients, they were 11 (9-13) for NoV and 12 (10-14) for RV. The difference was statistically significant among inpatients, but relatively small (1 point in a 20-point scale). About 20% more children with RV required rehydration when compared with children with NoV. CONCLUSIONS: NoV causes moderate to severe disease similar to RV in young children. This information should be useful for future evaluations of an eventual introduction of NoV vaccines in national immunization programs.

Effect of antibiotic, probiotic, and human rotavirus infection on colonisation dynamics of defined commensal microbiota in a gnotobiotic pig model.

We developed a gnotobiotic (Gn) pig model colonised with defined commensal microbiota (DMF) to provide a simplified and controlled system to study the interactions between intestinal commensals, antibiotics (ciprofloxacin, CIP), probiotics (Escherichia coli Nissle 1917, EcN) and virulent human rotavirus (VirHRV). The DMF included seven gut commensal species of porcine origin that mimic the predominant species in the infant gut. Gn piglets were divided into four groups: DMF control (non-treated), DMF+CIP (CIP treated), DMF+CIP+EcN (CIP/EcN treated), DMF+EcN (EcN treated) and inoculated orally with 105 cfu of each DMF strain. The pig gut was successfully colonised by all DMF species and established a simplified bacterial community by post-bacteria colonisation day (PBCD) 14/post-VirHRV challenge day (PCD) 0. Overall, Bifidobacterium adolescentis was commonly observed in faeces in all groups and time points. At PCD0, after six days of CIP treatment (DMF+CIP), we observed significantly decreased aerobic and anaerobic bacteria counts especially in jejunum (P<0.001), where no DMF species were detected in jejunum by T-RFLP. Following HRV challenge, 100% of pigs in DMF+CIP group developed diarrhoea with higher diarrhoea scores and duration as compared to all other groups. However, only 33% of pigs treated with EcN plus CIP developed diarrhoea. EcN treatment also enhanced the bacterial diversity and all seven DMF species were detected with a higher proportion of Bifidobacterium longum in jejunum in the DMF+CIP+EcN group on PBCD14/PCD0. Our results suggest that EcN increased the proportion of B. longum especially in jejunum and mitigated adverse impacts of antibiotic use during acute-infectious diarrhoea. The DMF model with a simplified gut commensal community can further our knowledge of how commensals and probiotics promote intestinal homeostasis and contribute to host health.

Rotavirus disease course among immunocompromised patients; 5-year observations from a tertiary care medical centre.

Rotavirus (RV) is highly endemic inside and outside hospital-settings. Immunocompromised children and adults are at risk of complicated rotavirus gastroenteritis (RVGE), but general rotavirus disease severity in this group remains poorly described and rotavirus testing is not routinely performed beyond infancy. We assessed rotavirus disease among immunocompromised hospitalized patients. METHODS: Rotavirus infections at a Dutch tertiary-care centre were identified from 5-year laboratory records. Rotavirus disease course was evaluated by chart review for each immunocompromised patient. In a matched case-control analysis, we assessed whether being immunocompromised predisposed to RVGE. Rotavirus testing practice for suspected infectious gastroenteritis in our hospital was determined over a 3-years period. RESULTS: Out of 4584 RV tests performed, 294 were positive among hospitalized patients. Immunocompromised patients represented 57% (N = 20) of adult, and 12% (N = 32) of paediatric RVGE. A complicated disease course occurred in 81% of them and 33% required adaptations in underlying disease management. Immunocompromised adults were 7.4 times more likely todevelop RVGE compared to non-immunocompromised matched hospital-controls. Rotavirus testing in adult patients with suspected infectious gastroenteritis was uncommon (12% tested). CONCLUSIONS: In our hospital, most adults with RVGE are immunocompromised compared to a much smaller proportion in children. RVGE in immunocompromised patients is associated with significant morbidity. Routine rotavirus testing beyond infancy should be recommended for immunocompromised patients with suspected infectious gastroenteritis.

Effects of Lactobacillus rhamnosus GG on the maturation and differentiation of dendritic cells in rotavirus-infected mice.

Rotavirus-related diarrhoea is considered one of the most important diseases in field animal production. In addition to the classic vaccine strategy, a number of studies have utilised probiotics, such as Lactobacillus rhamnosus GG (LGG), to prevent rotavirus-induced diarrhoea. Although it has been partially revealed that Toll-like receptors (TLRs) are involved in the LGG-mediated protection against rotavirus infection, the details of the underlying immunologic mechanisms remain largely unknown. In this study, three-to-four-week-old female BALB/c mice were divided into three groups and orally administered phosphate buffered saline (PBS), PBS plus rotavirus or LGG plus rotavirus, respectively. The differentiation and maturation of dendritic cells (DCs) were then determined by FACS, the expression levels of TLR-3 and nuclear factor kappa beta (NF-κB) were evaluated using real time PCR, and the production of inflammatory cytokines in mesenteric lymph nodes (MLNs) were determined by ELISA. The results demonstrated that rotavirus infection significantly increased the percentage of CD11c+CD11b+CD8a- DCs and decreased the percentage of CD11c+CD11b-CD8a+ DCs in MLNs. By contrast, the presence of LGG significantly decreased the percentage of CD11c+CD11b+CD8a- DCs and increased the percentage of CD11c+CD11b-CD8a+ DCs, which indicates that the differentiation of DCs is involved in the protective effects of LGG. Rotavirus infection also resulted in the increased expression of surface markers such as CD40, CD80 and MHC-II in DCs, and the administration of LGG significantly increased the expression level further. The mRNA levels of TLR-3 and NF-κB in the intestine and MLNs were also significantly increased in the presence of rotavirus, which was further increased in the presence of LGG. The production of inflammatory cytokines was also determined, and the results showed that rotavirus caused the increased production of interleukin (IL)-12 and tumour necrosis factor alpha; this effect was further enhanced by LGG. Meanwhile, although rotavirus infection led to the increased production of IL-6 and IL-10, the presence of LGG significantly decreased the mRNA levels of these cytokines. By contrast, rotavirus infection resulted in the decreased production of interferon gamma (IFN-γ), and the administration of LGG significantly increased the levels of IFN-γ. Taken together, the protective effects of LGG were partially due to the modulation of the differentiation and maturation of DCs, the increased production of TLR-3 and NF-κB, and the modulation of inflammatory cytokines.

Rotavirus antigen, cytokine, and neutralising antibody profiles in sera of children with and without HIV infection in Blantyre, Malawi.

BACKGROUND: Rotavirus and HIV infection are major causes of death among children in sub-Saharan Africa. A previous study reported no association between concomitant HIV infection and rotavirus disease severity among hospitalised children in Malawi. This study examined rotavirus antigenaemia and broader immune responses among HIV-infected and uninfected children. METHODS: Stored (-80°C), paired sera from acute and convalescent phases of Malawian children less than 5 years old, hospitalised for acute gastroenteritis in the primary study, collected from July 1997 to June 1999, were utilised. Among children older than 15 months, HIV infection was defined as the presence of HIV antibody in the blood, when confirmed by at least 2 established methods. For those younger than 15 months, nested polymerase chain reaction (PCR) amplification of proviral DNA was used for verification. All were followed for up to 4 weeks after hospital discharge. Rotavirus antigen levels in sera were measured with Premier™ Rotaclone® rotavirus enzyme immunoassay (EIA) kit. Acute-phase sera were examined for 17 cytokines, using Luminex fluorescent bead human cytokine immunoassay kit. Rotavirus-specific IgA and neutralising activity were determined by EIA and microneutralisation (MN) assay, respectively. Human strains and bovine-human reassortants were propagated in MA104 cells with serum-free Iscove's Modified Dulbecco's Medium (IMDM). Differences in results, from specimens with and without HIV infection, were analysed for statistical significance using the chi-square test. RESULTS: We detected rotavirus antigen in 30% of the HIV-infected and 21% HIV-uninfected, in the acute-phase sera. HIV-infected children developed slightly prolonged rotavirus antigenaemia compared to HIV-uninfected children. CONCLUSIONS: Rotavirus-specific IgA seroconversion rates and neutralising titres were similar in HIV-infected and HIV-uninfected children, thus, HIV infection had no major effect on immune responses to rotavirus infection.

The SRL peptide of rhesus rotavirus VP4 protein governs cholangiocyte infection and the murine model of biliary atresia.

Biliary atresia (BA) is a neonatal obstructive cholangiopathy that progresses to end-stage liver disease, often requiring transplantation. The murine model of BA, employing rhesus rotavirus (RRV), parallels human disease and has been used to elucidate mechanistic aspects of a virus induced biliary cholangiopathy. We previously reported that the RRV VP4 gene plays an integral role in activating the immune system and induction of BA. Using rotavirus binding and blocking assays, this study elucidated how RRV VP4 protein governs cholangiocyte susceptibility to infection both in vitro and in vivo in the murine model of BA. We identified the amino acid sequence on VP4 and its cholangiocyte binding protein, finding that the sequence is specific to those rotavirus strains that cause obstructive cholangiopathy. Pretreatment of murine and human cholangiocytes with this VP4-derived peptide (TRTRVSRLY) significantly reduced the ability of RRV to bind and infect cells. However, the peptide did not block cholangiocyte binding of TUCH and Ro1845, strains that do not induce murine BA. The SRL sequence within TRTRVSRLY is required for cholangiocyte binding and viral replication. The cholangiocyte membrane protein bound by SRL was found to be Hsc70. Inhibition of Hsc70 by small interfering RNAs reduced RRV's ability to infect cholangiocytes. This virus-cholangiocyte interaction is also seen in vivo in the murine model of BA, where inoculation of mice with TRTRVSRLY peptide significantly reduced symptoms and mortality in RRV-injected mice. CONCLUSION: The tripeptide SRL on RRV VP4 binds to the cholangiocyte membrane protein Hsc70, defining a novel binding site governing VP4 attachment. Investigations are underway to determine the cellular response to this interaction to understand how it contributes to the pathogenesis of BA. (Hepatology 2017;65:1278-1292).

Profile and Trends of Rotavirus Gastroenteritis in Under 5 children in India, 2012 - 2014, Preliminary Report of the Indian National Rotavirus Surveillance Network.

OBJECTIVE: To estimate the burden of rotavirus-associated gastroenteritis in India. METHODS: Hospital based surveillance network was established, with clinical evaluation and laboratory testing for rotavirus among children aged below 5 years hospitalized with acute gastroenteritis. RESULTS: Between September 2012 and December 2014, stool samples from 10207 children were tested and rotavirus was detected in 39.6% of cases. Infections were more commonly seen among younger children (<2 years). Detection rates were higher during cooler months of September February. Among rotavirus infected children, 64.0% had severe or very severe disease. G1P[8] was the predominant rotavirus genotype (62.7%) observed during the surveillance period. CONCLUSIONS: Surveillance data highlights the high rotavirus disease burden and emphasizes the need for close monitoring to reduce morbidity and mortality associated with rotavirus gastroenteritis in India.