The role of gut microbiota in human norovirus infections in transplant patients

肠道微生物群在移植患者诺如病毒感染中的作用

• 批准号: 10524718
• 负责人: Pearlie Pao Ee Chong
• 金额: $ 18.55万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-22 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10524718
• 关键词: Acute; Adherent Culture; Adult; Antibiotics; Antiviral Agents; B-Lymphocytes; Bacteroides; Bacteroides fragilis; Binding; Bioinformatics; Blood Group Antigens; CD8-Positive T-Lymphocytes; Cells; Cessation of life; Childhood; Chronic; Chronic diarrhea; Clinical; Clinical Trials; Computerized Medical Record; Data; Dendritic cell activation; Enteral; Enterobacteriaceae; Etiology; Exhibits; Family; Flow Cytometry; Foundations; Future; Gastroenteritis; Goals; Grant; Health system; Hematopoietic Stem Cell Transplantation; Human; Immune response; Immunocompromised Host; Immunology; Immunosuppression; In Vitro; Incubated; Individual; Infection; Inflammatory; Innate Immune Response; Integration Host Factors; Interferon Type I; Interferon-alpha; Interferons; Interleukin-10; Interleukin-4; Interleukin-5; Intestines; Klebsiella; Malnutrition; Mediating; Metagenomics; Modeling; Molecular; Mus; Natural History; Norovirus; Organ; Pathogenesis; Pathogenicity; Patients; Physicians; Play; Polysaccharides; Pre-Clinical Model; Probiotics; Production; Proteins; Proteomics; RNA; Resolution; Role; Sample Size; Sampling; Scientist; Serum; Severities; Shotgun Sequencing; Solid; Surface; T cell response; TNF gene; Taxonomy; Therapeutic; Training; Transplant Recipients; United States; Viral; Viral Pathogenesis; Virus; Virus Replication; Wasting Syndrome; abstracting; cohort; cost; cytokine; enteric virus infection; experimental study; fecal transplantation; gut bacteria; gut microbiome; gut microbiota; human microbiota; insight; member; microbiome signature; microbiota profiles; next generation sequencing; novel; persistent symptom; response; skills; stool sample; tool

PROJECT SUMMARY Human norovirus (HuNoV) is the leading cause of acute gastroenteritis in the United States, resulting in $4.2 billion in direct health system costs annually. Due to underlying immunosuppression and the lack of effective antiviral therapeutics, transplant patients may develop serious sequelae from HuNoV infections. Though bacterial gut microbiota has been shown to enhance replication and pathogenesis of enteric viruses in preclinical models, its role in HuNoV infection remains largely unknown. In this project, we aim to gain greater mechanistic insights into how gut microbiota modulate HuNoV infection in transplant patients. Our central hypothesis is that transplant patients with symptomatic HuNoV infection will have a gut microbiome signature showing an enrichment of specific gut microbiota (Enterobacteriaceae) that facilitate infection of HIEs, and those who develop chronic symptoms from HuNoV infection will have a concomitant depletion of specific gut microbiota that modulate host innate immune responses (type 1 interferons). In Aim 1, we will further define both gut microbiome and host factor differences in transplant patients ±HuNoV infections. First, we will establish a larger cohort of adult and pediatric transplant patients and collect longitudinal stool specimens. Then, we will perform comprehensive gut microbiome profiling (metagenomic shotgun sequencing and bacterial qPCR) to confirm our preliminary results. We predict that HuNoV-infected transplant patients will have significantly different gut microbiota signatures compared to uninfected counterparts, and that higher intensity of immunosuppression and high antibiotic load will correspond with chronic diarrhea in HuNoV-infected transplant patients. In Aim 2, we will determine if Enterobacteriaceae facilitate HuNoV infection using an in vitro HIE model. First, we will infect jejunal HIEs with HuNoV and co-incubate HuNoV with various Enterobacteriaceae spp. Then, we will perform RNA extractions and quantitative HuNoV RT-qPCR to evaluate the effect of co-incubating various Enterobacteriaceae spp. on viral replication. We predict that Enterobacteriaceae promotes HuNoV infection of HIEs. If this is the case, we will investigate if this is a phenomenon observed only in HBGA-expressing members of Enterobacteriaceae. In Aim 3, we will determine if transplant patients with chronic symptomatic HuNoV infections have different systemic cytokine signatures compared to uninfected counterparts. We will perform bulk cytokine analysis on serum samples utilizing Isoplexis, a novel functional proteomic profiling platform. We predict that transplant patients with chronic diarrhea from HuNoV infection will exhibit a paucity of genus Bacteroides, resulting in depletion of type 1 interferons, which then leads to a decreased Th1 immune response, increased Th2 immune response and increased expression of Th2-predominant cytokines (IL-4, IL-5, IL-10). The proposed experiments, training and didactic coursework in this K23 will equip the candidate (Dr. Chong) with unique skillsets that will enable her transition to independence as a physician scientist in gut microbiota-HuNoV interactions in transplant patients.

项目总结