Sitang Gong - Academia.edu (original) (raw)

Papers by Sitang Gong

Viruses

Human norovirus (HuNoV) is one of the major pathogens of acute nonbacterial gastroenteritis. Due ... more Human norovirus (HuNoV) is one of the major pathogens of acute nonbacterial gastroenteritis. Due to the lack of a robust and reproducible in vitro culture system and an appropriate animal model, the mechanism underlying HuNoV-caused diarrhea remains unknown. In the current study, we found that HuNoV transfection induced the expression of aquaporin 1 (AQP1), which was further confirmed in the context of virus infection, whereas the enterovirus EV71 (enterovirus 71) did not have such an effect. We further revealed that VP1, the major capsid protein of HuNoV, was crucial in promoting AQP1 expression. Mechanistically, HuNoV induces AQP1 production through the NF-κB signaling pathway via inducing the expression, phosphorylation and nuclear translocation of p65. By using a model of human intestinal epithelial barrier (IEB), we demonstrated that HuNoV and VP1-mediated enhancement of small molecule permeability is associated with the AQP1 channel. Collectively, we revealed that HuNoV induce...

Uncontrolled microbe-triggered inflammation results in multiple organ injury and shock in sepsis.... more Uncontrolled microbe-triggered inflammation results in multiple organ injury and shock in sepsis. However, the regulatory mechanisms that restrict cytokine storm are still elusive. Using gene screening, we identified an immunoglobulin-like receptor called Signaling Lymphocyte Activation Molecular Family-7 (SLAMF7), as a key regulator of inflammation during sepsis. We found that the expression of SLAMF7 on monocytes and macrophages was significantly elevated in sepsis subjects and septic mice. SLAMF7 attenuated TLR dependent MAPKs and NF-κB signaling activation by co-operating with Src homology 2-containing inositol‑5'‑phosphatase1 (SHIP1). Furthermore, SLAMF7 interacted with SHIP1 and TNF receptor associated factor 6 (TRAF6) to inhibite K63 ubiquitination of TRAF6. In addition, we found that intracellular domain tyrosine phosphorylation sites of SLAMF7 and phosphatase domain of SHIP1 were indispensable for the interaction of SLAMF7/SHIP1/TRAF6 and the modulation of cytokines pro...

Theranostics, 2021

Rationale: Children usually develop less severe symptoms responding to Coronavirus Disease 2019 (... more Rationale: Children usually develop less severe symptoms responding to Coronavirus Disease 2019 (COVID-19) than adults. However, little is known about the molecular alterations and pathogenesis of COVID-19 in children. Methods: We conducted plasma proteomic and metabolomic profilings of the blood samples of a cohort containing 18 COVID-19-children with mild symptoms and 12 healthy children, which were enrolled from hospital admissions and outpatients, respectively. Statistical analyses were performed to identify molecules specifically altered in COVID-19-children. We also developed a machine learning-based pipeline named inference of biomolecular combinations with minimal bias (iBM) to prioritize proteins and metabolites strongly altered in COVID-19-children, and experimentally validated the predictions. Results: By comparing to the multi-omic data in adults, we identified 44 proteins and 249 metabolites differentially altered in COVID-19-children against healthy children or COVID-19-adults. Further analyses demonstrated that both deteriorative immune response/inflammation processes and protective antioxidant or anti-inflammatory processes were markedly induced in COVID-19-children. Using iBM, we prioritized two combinations that contained 5 proteins and 5 metabolites, respectively, each exhibiting a total area under curve (AUC) value of 100% to accurately distinguish COVID-19-children from healthy children or COVID-19-adults. Further experiments validated that all the 5 proteins were up-regulated upon coronavirus infection. Interestingly, we found that the prioritized metabolites inhibited the expression of pro-inflammatory factors, and two of them, methylmalonic acid (MMA) and mannitol, also suppressed coronaviral replication, implying a protective role of these metabolites in COVID-19-children. Conclusion: The finding of a strong antagonism of deteriorative and protective effects provided new insights on the mechanism and pathogenesis of COVID-19 in children that mostly underwent mild symptoms. The identified metabolites strongly altered in COVID-19-children could serve as potential therapeutic agents of COVID-19.

Journal of Parenteral and Enteral Nutrition, 2018

BACKGROUND Nutrition support is important for clinical management to improve outcomes of infants ... more BACKGROUND Nutrition support is important for clinical management to improve outcomes of infants following congenital heart surgery. Protein-enriched and energy-enriched formula (PE-formula) may help provide adequate nutrition and promote wound healing. However, the effects and tolerance of increased protein and energy intakes of these infants have not been well defined. OBJECTIVE To evaluate nutrition effects and tolerance of a PE-formula compared with the standard formula (S-formula) in infants in the first 5 days after congenital heart surgery. METHODS Fifty infants were randomly assigned to S-formula (S-group, n = 24) or PE-formula (PE-group, n = 26). Daily nutrient intakes and tolerance were recorded. Plasma amino acid concentrations were measured. Cumulative energy balance and nitrogen balance were calculated. RESULTS Nutrient intakes were significantly higher in the PE-group after day 1, and all met the adequate intakes as early as day 2. Nitrogen balance in the PE-group met ...

BMC Infectious Diseases, 2021

Background The incidence of hand foot and mouth disease (HFMD) has increased in recent years, mak... more Background The incidence of hand foot and mouth disease (HFMD) has increased in recent years, making it a very common childhood illness worldwide. The relationship between different enterovirus genotypes and disease severity is not clearly understood. Given that enteroviruses are transmitted through the gastrointestinal tract, we hypothesized that variation in intestinal microorganisms of the host might play a role in the prognosis of HFMD. Methods We carried out a meta-transcriptomic-wide association study of fecal samples obtained from a cohort of children (254 patients, 227 tested positive for enterovirus, including 16 patients co-infectied with 2 kinds of enterovirus) with mild and severe HFMD and healthy controls. Results We found there was no significant difference in the amount of each virus type between the mild and severe cases. Genes of enterovirus 71 (EV71) and coxsackievirus A (CV-A) from the severe and mild cases did not show significant clustering. Clostridium sp. L2-5...

Virology Journal, 2020

Background The new emerging coronavirus disease 2019 (COVID-19) overall shares similar symptoms w... more Background The new emerging coronavirus disease 2019 (COVID-19) overall shares similar symptoms with other common respiratory viral infections. We aimed in this study to compare COVID-19 and human adenovirus (HAdV) infections in pediatric patients regarding the frequencies of major clinical symptoms and the potential disparities in laboratory and imaging parameters. Methods Following a case–control-like design, we built 72 age-matched pediatric COVID-19 and HAdV patient pairs. Their early symptoms and laboratory and imaging characteristics were then retrieved and compared. Results Fever and cough were the most common symptoms for both infections but were seen more often in HAdV than in COVID-19 patients (92% vs. 66% and 60% vs. 18%, respectively). Compared with COVID-19 patients, children with HAdV infection had statistically significantly higher values of neutrophil count, neutrophil percentage, activated partial thromboplastin time, prothrombin time, lactate dehydrogenase, C-react...

Nature Medicine, 2020

We report epidemiological and clinical investigations on ten pediatric SARS-CoV-2 infection cases... more We report epidemiological and clinical investigations on ten pediatric SARS-CoV-2 infection cases confirmed by realtime reverse transcription PCR assay of SARS-CoV-2 RNA. Symptoms in these cases were nonspecific and no children required respiratory support or intensive care. Chest X-rays lacked definite signs of pneumonia, a defining feature of the infection in adult cases. Notably, eight children persistently tested positive on rectal swabs even after nasopharyngeal testing was negative, raising the possibility of fecal-oral transmission. The outbreak of SARS-CoV-2 (formerly 2019-nCoV) infection emerged in December 2019 in Wuhan, Hubei Province, China 1,2. By 25 February 2020, there had been 77,780 confirmed cases including 2,666 deaths in China and over 2,459 confirmed cases in 33 other countries 3. The genome of the new virus and early epidemiological and clinical features of the infection in adults have been reported 4-6. The infection is estimated to have a mean incubation period of 5.2 d and commonly causes fever, cough, myalgia and pneumonia in patients 4. To date there is a paucity of information regarding SARS-CoV-2 infection in children. We here report the epidemiological and clinical features of ten children infected with SARS-CoV-2 and tested for evidence of viral excretion through the gastrointestinal and respiratory tracts. By 20 February 2020, a total of 745 children and 3,174 adults, most of whom had either close contact with diagnosed patients or had members of the family reporting familial outbreaks in the previous 2 weeks, were screened by nasopharyngeal swab real-time PCR with reverse transcription (RT-PCR) for SARS-CoV-2 infection. Overall, 10 children (1.3%) and 111 adults (3.5%) tested positive. The 2.7-fold difference between children and adults is statistically significant (P = 0.002). All ten pediatric patients were admitted to our hospital, a treatment center for SARS-CoV-2 infection designated by the local municipal government.

Journal of Allergy and Clinical Immunology, 2020

Background: Very-early-onset inflammatory bowel disease (VEOIBD) is a chronic inflammatory diseas... more Background: Very-early-onset inflammatory bowel disease (VEOIBD) is a chronic inflammatory disease of the gastrointestinal tract occurring during infancy or early childhood. NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome has emerged as a crucial regulator of intestinal homeostasis; however, whether NLRP3 variants may modify VEOIBD risk is unknown. Objective: We sought to investigate whether and how a rare NLRP3 variant, found in 3 patients with gastrointestinal symptoms, contributes to VEOIBD development. Methods: Whole-exome sequencing and bioinformatic analysis were performed to screen disease-associated NLRP3 variants from a cohort of children with VEOIBD. Inflammasome activation was determined in reconstituted HEK293T human embryonic kidney cells with NLRP3 inflammasome components, doxycycline-inducible NLRP3 macrophages, as well as PBMCs and biopsies from patients with NLRP3 variants. Pathogenesis of the variants was determined using a dextran sulfate sodium-induced acute colitis model. Results: We identified a dominant gain-of-function missense variant of NLRP3, encoded by rs772009059 (R779C), in 3 patients with gastrointestinal symptoms. Functional analysis revealed that R779C increased NLRP3 inflammasome activation and pyroptosis in macrophages. This was mediated by enhanced deubiquitination of NLRP3 via binding with deubiquitinases BRCC3 and JOSD2, which are highly expressed in myeloid cells. In a dextran sulfate sodium-induced acute colitis model, NLRP3-R779C in hematopoietic cells resulted in more severe colitis, which can be ameliorated via knockdown of BRCC3 or JOSD2. Conclusions: BRCC3 and JOSD2 mediate NLRP3-R779C deubiquitination, which promotes NLRP3 inflammasome activation and the risk of developing VEOIBD. (J Allergy Clin Immunol 2020;nnn:nnn-nnn.)

BioMed Research International, 2020

Background. CD147/basigin (Bsg), a transmembrane glycoprotein, activates matrix metalloproteinase... more Background. CD147/basigin (Bsg), a transmembrane glycoprotein, activates matrix metalloproteinases and promotes inflammation. Objective. The aim of this study is to explore the clinical significance of CD147 in the pathogenesis of inflammatory bowel disease (IBD). Results. In addition to monocytes, the clinical analysis showed that there is no significance obtained in leucocyte, neutrophil, eosinophil, basophil, and erythrocyte between IBD and controls. Immunohistochemistry analysis showed that CD147 was increased in intestinal tissue of patients with active IBD compared to that in the control group. What is more, CD147 is involved in intestinal barrier function and intestinal inflammation, which was attributed to the fact that it has an influence on MCT4 expression, a regulator of intestinal barrier function and intestinal inflammation, in HT-29 and CaCO2 cells. Most importantly, serum level of CD147 content is higher in active IBD than that in inactive IBD or healthy control, whic...

Frontiers in Endocrinology, 2020

Idiopathic central precocious puberty (ICPP) is a relatively common condition in preadolescent gi... more Idiopathic central precocious puberty (ICPP) is a relatively common condition in preadolescent girls, and its pathogenesis remains to be uncovered. A variety of studies have highlighted the association of gut microbiota (GM) with endocrine diseases, such as obesity, which is commonly associated with ICPP. However, the relationship between GM and ICPP remains unexplored. Feces samples were collected from 25 girls with ICPP (ICPP group) and 23 healthy girls (Control group). We applied 16S rDNA sequencing to compare the GM between two groups. The ICPP group had higher GM diversity and was enriched for several GM species, including Ruminococcus gnavus, Ruminococcus callidus, Ruminococcus bromii, Roseburia inulinivorans, Coprococcus eutactus, Clostridium leptum, and Clostridium lactatifermentans, which are known to be associated with obesity and are related to the production of short-chain fatty acids. Additionally, 36 candidate GM biomarkers for patients with ICPP screening were identified with high accuracy (AUC = 0.95, 95% CI 0.88 to 1). We observed that the GM of the ICPP group was enriched for the microbial functions of cell motility, signal transduction, and environmental adaptation. Positive correlations were also detected between Fusobacterium and follicle-stimulating hormone, and Gemmiger and luteinizing hormone. This study documents relationships between GM and ICPP, and the implication of these findings remains to be determined.

Clinical & Experimental Allergy, 2019

Background: Helicobacter pylori neutrophil-activating protein (NAP) is an immune modulator with a... more Background: Helicobacter pylori neutrophil-activating protein (NAP) is an immune modulator with anti-Th2 inflammation activity that can be used to prevent IgE-mediated allergic reactions. Cholera toxin B (CTB) is a mucosal adjuvant that can induce antigen tolerance. Bacillus subtilis spores are an ideal vehicle for the oral delivery of heterologous antigens. Objective: We investigated the therapeutic effect of recombinant NAP B subtilis spores on peanut allergies in a mouse model. Methods: Female C3H/HeJ mice were sensitized and challenged with peanut extract by oral administration. Before challenge, recombinant NAP and CTB-NAP (CNAP) spores were orally administered to sensitized mice for 4 weeks. Faecal peanut-specific IgA and serum-specific IgE, IgG1, and IgG2a levels were measured, and the intestinal microbiota was analysed. Mice were intraperitoneally injected with anti-CD25 antibodies for regulatory T cell (Treg) depletion to evaluate the efficacy of Tregs in preventing peanut allergy. After challenge, anaphylactic reactions, plasma histamine, Tregs, and splenocyte interleukin (IL)-10, IL-4, IL-5 and interferon-γ (IFN-γ) levels were evaluated. Results: After 4 weeks of recombinant spore treatment, faecal IgA levels and serum IgG2a levels were increased, while serum IgG1 and IgE levels were reduced. Intestinal microbiota analysis revealed that CNAP spores increased the taxonomic abundance of Firmicutes at the phylum level and Clostridia at the class level. After challenge, the administration of NAP or CNAP spores to mice was found to ameliorate anaphylactic reactions and decrease plasma histamine levels. Administration of NAP or CNAP spores also enhanced IL-10 and IFN-γ secretion, and suppressed IL-4 and IL-5 secretion. The protective effect of CNAP spores was more pronounced than that of NAP spores; this therapeutic effect was lost after Treg depletion. Conclusions and Clinical Relevance: Recombinant NAP spores successfully suppressed Th2 inflammation via the up-regulation of Tregs; this may serve as a novel therapeutic approach for treating food allergies.

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Gastroenterology research and practice, 2018

Nontyphoidal infection is a common cause for acute bacterial gastroenteritis in children in China... more Nontyphoidal infection is a common cause for acute bacterial gastroenteritis in children in China. There have been no reports of the prevalence of lactose intolerance or food allergies in children with nontyphoidal infection. The aim of this study was to characterize nontyphoidal gastroenteritis in a tertiary children's hospital and evaluate clinical presentation, lactose intolerance, and food allergies in children with prolonged nontyphoidal gastroenteritis. A retrospective case-series analysis was carried out in a tertiary children's hospital in Guangzhou, China. We included all infants and children who were diagnosed with nontyphoidal gastroenteritis between 1 January 2014 and 31 December 2016. Patients' clinical features, feeding patterns, laboratory tests, and treatment outcomes were reviewed. A total of 142 infants and children were diagnosed with nontyphoidal gastroenteritis. 52.1% of cases occurred in infants ≤ 12 months of age and the majority (89.4%) in childre...

Emerging microbes & infections, Jan 10, 2018

Enterovirus D68 (EV-D68) has been increasingly associated with severe respiratory illness and neu... more Enterovirus D68 (EV-D68) has been increasingly associated with severe respiratory illness and neurological complications in children worldwide. However, no vaccine is currently available to prevent EV-D68 infection. In the present study, we investigated the possibility of developing a virus-like particle (VLP)-based EV-D68 vaccine. We found that co-expression of the P1 precursor and 3CD protease of EV-D68 in Pichia pastoris yeast resulted in the generation of EV-D68 VLPs, which were composed of processed VP0, VP1, and VP3 capsid proteins and were visualized as ~30 nm spherical particles. Mice immunized with these VLPs produced serum antibodies capable of specifically neutralizing EV-D68 infections in vitro. The in vivo protective efficacy of the EV-D68 VLP candidate vaccine was assessed in two challenge experiments. The first challenge experiment showed that neonatal mice born to the VLP-immunized dams were fully protected from lethal EV-D68 infection, whereas in the second experime...

Viruses, Jan 30, 2018

In recent years, enterovirus D68 (EVD68) has been reported increasingly to be associated with sev... more In recent years, enterovirus D68 (EVD68) has been reported increasingly to be associated with severe respiratory tract infections and acute flaccid myelitis (AFM) in children all over the world. Yet, no effective vaccines or antiviral drugs are currently available for EVD68. Although several experimental animal models have been developed, immunogenicity and protective efficacy of inactivated EVD68 vaccines has not been fully evaluated. To promote the development of vaccines, we established an Institute of Cancer Research (ICR) suckling mouse model of EVD68 infection in this study. The results showed that ICR neonatal mice up to about nine days of age were susceptible to infection with EVD68 clinical strain US/MO/14-18947 by intraperitoneal injection. The infected mice exhibited progressive limb paralysis prior to death and the mortality of mice was age- and virus dose-dependent. Tissue viral load analysis showed that limb muscle and spinal cord were the major sites of viral replicat...

FEMS microbiology letters, 2017

Previous epidemiologic studies have demonstrated an inverse association between Helicobacter pylo... more Previous epidemiologic studies have demonstrated an inverse association between Helicobacter pylori infection and the frequency of allergic asthma. The neutrophil-activating protein (NAP) of H. pylori has been identified as a modulator possessing anti-Th2 inflammation activity. Here, we sought to determine whether systemic or mucosal pre-administration of recombinant H. pylori NAP (rNAP) could prevent ovalbumin (OVA)-induced allergic asthma in mice. Mice were exposed to purified rNAP through intraperitoneal injection or inhalation and then sensitized with OVA. Following a challenge with aerosolized OVA, the bronchoalveolar lavage fluid (BALF) cell count, lung tissue histology, BALF cytokines and serum IgE were evaluated. Both intraperitoneal injection and inhalation of rNAP prior to OVA sensitization significantly reduced eosinophil accumulation and inflammatory infiltration in lung tissue in OVA-induced asthma mice; eosinophils were reduced in the BALF of rNAP-treated mice. In addi...

Emerging microbes & infections, Jan 7, 2016

Zika virus (ZIKV) is an emerging mosquito-borne flavivirus that can potentially threaten South Ch... more Zika virus (ZIKV) is an emerging mosquito-borne flavivirus that can potentially threaten South China. A Chinese family of four returning from Venezuela to China was found to be positive for ZIKV when the youngest son's fever was first detected at an airport immigration inspection. They were isolated temporarily in a local hospital in Enping city, Guangdong province, where their clinical data were recorded and urine and saliva were collected to isolate ZIKV and to obtain viral sequences. All of them except the mother presented mild symptoms of rash and fever. Envelope gene sequences from the father, daughter and son were completely identical. Phylogenetic analysis demonstrated that this strain is similar to several imported strains reported in recent months, which are all clustered into a group isolated from 2015 ZIKA outbreaks in Brazil. Together with the climatic features in Venezuela, New York and Guangdong in February, it can be concluded that our subjects are imported cases ...

Frontiers in public health, 2016

Prior authorization, audit and feedback, and pay for performance are the three core "active&... more Prior authorization, audit and feedback, and pay for performance are the three core "active" strategies of antimicrobial stewardship program (ASP), yet little is known about the individual or combined benefits of such programs, particularly in a pediatric setting. The aim of this study was to compare these core ASP strategies and determine the incremental effect of financially punished audit and feedback. During the journey to the Joint Commission International accreditation, a tertiary pediatric medical center performed two different hospital-wide stewardship interventions in succession. The first stage without formalized ASPs served as pre-intervention period, January 2011 to April 2011. The ASP used prior authorization alone during the first-intervention period, May 2011 to September 2011. In October 2011, financially punished audit and feedback was introduced, marking the start of the second-intervention period, October 2011 to November 2012. We compared the difference...

Neural Plasticity, 2015

Cytoskeleton dynamics are critical phenomena that underpin many fundamental cellular processes. C... more Cytoskeleton dynamics are critical phenomena that underpin many fundamental cellular processes. Collapsin response mediator proteins (CRMPs) are highly expressed in the developing nervous system, mediating growth cone guidance, neuronal polarity, and axonal elongation. However, whether and how CRMPs associate with microtubules and actin coordinated cytoskeletal dynamics remain unknown. In this study, we demonstrated that CRMP2 and CRMP4 interacted with tubulin and actinin vitroand colocalized with the cytoskeleton in the transition-zone in developing growth cones. CRMP2 and CRMP4 also interacted with one another coordinately to promote growth cone development and axonal elongation. Genetic silencing of CRMP2 enhanced, whereas overexpression of CRMP2 suppressed, the inhibitory effects of CRMP4 knockdown on axonal development. In addition, knockdown of CRMP2 or overexpression of truncated CRMP2 reversed the promoting effect of CRMP4. With the overexpression of truncated CRMP2 or CRMP4...

Journal of medical microbiology, 2015

Helicobacter pylori infection is a major risk factor for chronic gastritis, digestive ulcers, gas... more Helicobacter pylori infection is a major risk factor for chronic gastritis, digestive ulcers, gastric adenocarcinoma and lymphoma. Due to the decreasing efficacy of anti-H. pylori antibiotic therapy in clinical practice, there is renewed interest in the development of anti-H. pylori vaccines. Bacillus subtilis is non-pathogenic and can produce endospores, which can survive under extreme conditions. These features make the B. subtilis spore an ideal vehicle for delivery of heterologous antigens to extreme environments such as the gastrointestinal tract. In this study, we displayed H. pylori urease B protein on the B. subtilis spore coat using the spore coat protein CotC as a fusion partner. Western blot analyses were used to verify urease B surface expression on spores. Recombinant spores displaying the urease B antigen were used for oral immunization and were shown to generate humoral response in mice. Urease B-specific secretory IgA in faeces and IgG in serum reached significant le...

Journal of Medical Case Reports, 2013

Introduction Duodenal duplication is a rare congenital malformation and has been reported as a ra... more Introduction Duodenal duplication is a rare congenital malformation and has been reported as a rare cause of recurrent acute pancreatitis. Hemorrhagic ascites has been reported in only one case of duodenal duplication. Case presentation An 11-year-old Chinese girl presented with abdominal pain, hematemesis and dark stools. On admission, an abdominal examination revealed a moderately distended abdomen with diffuse tenderness. Biochemical investigations showed increased serum levels of amylase, lipase, and urine amylase. An abdominal computed tomography scan and magnetic resonance imaging scan revealed an enlarged and heterogeneous pancreas with poorly delineated borders. There was a cystic lesion measuring 25mm × 48mm × 28mm, located between the descending portion of her duodenum and the head of her pancreas. There were massive effusion signals in her abdominal cavity. An exploratory laparotomy was performed. A tubular cyst measuring 32mm × 52mm × 30mm was found in the second part of...