Gut microflora: Impact on neonatal immunity, viral gastroenteritis and vaccines

肠道菌群：对新生儿免疫力、病毒性胃肠炎和疫苗的影响

• 批准号: 8663182
• 负责人: Gireesh Rajashekara
• 金额: $ 41.5万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-06-01 至 2017-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8663182
• 关键词: Address; Adjuvant; Adoption; Affect; African; Allergic; Anaerobic Bacteria; Anatomy; Animal Model; Animals; Anti-Inflammatory Agents; Anti-inflammatory; Antibiotic Therapy; Antibiotics; Antibodies; Attenuated; Bacteria; Biological Markers; Biological Products; Birth; Cessation of life; Child; Childhood; Collaborations; Communicable Diseases; Competence; Complex; Confounding Factors (Epidemiology); Country; Data; Developed Countries; Developing Countries; Development; Diarrhea; Diet; Disease; Economics; Effectiveness; Enteral; Epithelial Cells; Equilibrium; Escherichia coli; Expressed Sequence Tags; Family suidae; Food Hypersensitivity; Gene Expression Profile; Genes; Gnotobiotic; Goals; Homeostasis; Human; Hypersensitivity; Immune; Immune response; Immune system; Immunity; Immunoglobulin A; Inbreeding; Incidence; Indigenous; Infant; Infant Health; Infantile Diarrhea; Infection; Inflammation; Inflammatory; Inflammatory Bowel Diseases; Inflammatory Response; Intestines; Investigation; Knowledge; Kwashiorkor; Lactobacillus; Lactobacillus acidophilus; Lead; Licensing; Life; Malnutrition; Maternal antibody; Mediating; Metagenomics; Microarray Analysis; Microbe; Milk; Modeling; Mothers; Mucosal Immunity; Mus; Neonatal; Newborn Animals; Oral; Pathogenesis; Pathogenicity; Pathway interactions; Permeability; Physiology; Play; Predisposition; Probiotics; Property; Public Health; Recovery; Regulation; Regulatory T-Lymphocyte; Resistance; Role; Rotavirus; Rotavirus Infections; Rotavirus Vaccines; Rotavirus disease; Serum; Severities; Severity of illness; Symptoms; Syndrome; Testing; Therapeutic Intervention; Tight Junctions; Transplantation; Treatment Cost; Twin Multiple Birth; Vaccinated; Vaccine Adjuvant; Vaccine Design; Vaccines; Viral; Viral Gastroenteritis; Viral Vaccines; Virulent; Virus; Weaning; base; commensal microbes; cost; experience; feeding; food antigen; gene function; gut microbiota; gut microflora; high risk infant; immunoregulation; improved; infant morbidity/mortality; innovation; insight; intestinal homeostasis; metabolomics; microbial; microbiome; mortality; neonate; oral vaccine; response; sugar; vaccine efficacy

DESCRIPTION (provided by applicant): Rotavirus (RV) is a leading global cause of childhood diarrhea. Current attenuated human RV (AttHRV) oral vaccines are effective in infants in developed countries, but for unexplained reasons, they lack efficacy in impoverished countries where diarrhea mortality is highest. Alternative affordable strategies are urgently needed to reduce diarrheal diseases and enhance oral vaccine efficacy. Malnutrition (kwashiorkor) and frequent antibiotic usage in infants affect the gut microbiome and barrier integrity, likely compromising gut immunity and predisposing infants to diarrheal illness, but their impact on HRV infection is uncharacterized. Studies of gnotobiotic (Gn) animals have revealed that probiotics or commensal microflora are crucial for gut immune maturation and homeostasis, but the mechanisms involved and their roles in modulating viral diarrheas or enhancing oral vaccine efficacy are unclear. Neonates undergo progressive changes in the gut microflora which we will model by colonizing Gn pigs with Lactobacillus spp (Gram, G+), E. coli (G- ), both, or a commensal cocktail from conventional piglets. Gn pigs resemble infants in size, anatomy, physiology, development of mucosal immunity and are the only animal model susceptible to HRV diarrhea. Our investigation of how the selected probiotics/commensals modulate gut homeostasis and immune responses and impact enteric diseases and vaccines will permit their rational use as biotherapeutic agents and/or adjuvants. We hypothesize that selected G+ and G- gut microflora will modulate different host cellular pathways leading to immunostimulatory, but balanced (Th1/Th2/Th17/Treg) responses that enhance efficacy of RV vaccines or immuno-regulatory (Treg) responses that moderate HRV diarrhea. Further, humanized, outbred Gn pigs are a unique model to study how microbiota and diet contribute to malnutrition and HRV disease severity under conditions that constrain confounding variables in ways not possible in infants. In Aim 1, we determine how selected G+ or G- probiotics, both, or the commensal cocktail modulates immune responses, gut homeostasis and HRV pathogenicity. Then we test the impact of antibiotics on the commensal microflora and on these same parameters. In Aim 2, we determine how defined probiotics or commensals modulate protective immunity to AttHRV oral vaccine. In Aim 3, in collaboration with Jeff Gordon, we develop a humanized Gn pig model to study the interaction of microbiota x diet (from African twins discordant for kwashiorkor) on severe malnutrition and HRV pathogenicity and identify microbial biomarkers to aid in vaccine design or therapeutic interventions. Effects of the probiotics/commensals/microbiota will be compared by intestinal transcriptome profiling (pig microarrays, 44K ESTs), metagenomics, metabolomics and metatranscriptomics, gut barrier integrity (sugar permeability, tight junction genes, serum LPS), and induction of innate and adaptive immune responses, to establish the immunoregulatory/immunostimulatory profiles. Our innovative studies will address gaps in knowledge of gut immune maturation and homeostasis and interactions between gut microflora and enteropathogenic viruses or oral vaccines. Our findings will contribute to alternative low cost probiotic treatments applicable to infants (or mothers) to moderate HRV disease, enhance oral vaccine efficacy, and reduce infant morbidity and mortality.

描述（由申请人提供）：轮状病毒（RV）是儿童腹泻的全球主要原因。当前的人RV（ATTHRV）口服疫苗在发达国家的婴儿有效，但是由于无法解释的原因，在腹泻死亡率最高的贫困国家中，它们缺乏疗效。迫切需要采取替代性负担得起的策略来减少腹泻疾病并提高口服疫苗功效。婴儿的营养不良（kwashiorkor）和婴儿频繁的抗生素使用会影响肠道微生物组和屏障完整性，可能会损害肠道免疫力，并使婴儿诱发腹泻病，但它们对HRV感染的影响未经特征。 gnotobiotic（GN）动物的研究表明，益生菌或共生菌群对于肠道免疫成熟和稳态至关重要，但是所涉及的机制及其在调节病毒性腹泻或增强口服疫苗功效中的作用尚不清楚。新生儿经历了肠道菌群的进行性变化，我们将通过将GN猪与乳酸杆菌（Gram，G+），大肠杆菌（G-），或来自常规小猪的共生鸡尾酒进行建模。 GN猪类似于大小，解剖学，生理，粘膜免疫的发育，是唯一容易患有HRV腹泻的动物模型。我们对所选益生菌/份量如何调节肠道稳态以及免疫反应以及影响肠道疾病和疫苗的调查将使它们合理用作生物治疗剂和/或辅助因素。我们假设选定的G+和G-ut菌群将调节不同的宿主细胞途径，导致免疫刺激性，但平衡（TH1/TH2/TH17/TREG）响应，从而增强RV疫苗或免疫调节（TREG）反应的功效。此外，人性化的，杂种的GN猪是研究微生物群和饮食如何促进营养不良和HRV疾病严重程度的独特模型，这些条件在婴儿不可能以可能的方式限制了混淆变量的情况下。在AIM 1中，我们确定选择的G+或G-益生菌是如何调节免疫反应，肠稳态和HRV致病性的。然后，我们测试抗生素对共生菌群和这些相同参数的影响。在AIM 2中，我们确定定义的益生菌或共生如何调节对ATTHR口服疫苗的保护性免疫。在AIM 3中，与Jeff Gordon合作，我们开发了一种人源化的GN Pig模型，以研究严重营养不良和HRV的病原体的微生物X饮食（来自非洲双胞胎与Kwashiorkor的不一致）的相互作用，并确定微生物生物标志物以帮助疫苗设计或治疗性设计或治疗疗法设计或治疗性设计或治疗性生物标志物干预措施。益生菌/共生/微生物的影响将通过肠道转录组分析（猪微阵列，44K EST），宏基因组学，代谢组学和元文字分类组，肠道屏障完整性（糖渗透性，紧密连接基因，血清LPS，血清LPS），以及固定性的含量和适应性来比较。免疫反应，以建立免疫调节/免疫刺激谱。我们的创新研究将解决有关肠道免疫成熟和稳态知识的差距，以及肠道菌群与肠病病毒或口服疫苗之间的相互作用。我们的发现将有助于替代适用于婴儿（或母亲）适应中度HRV疾病，提高口服疫苗功效并降低婴儿的发病率和死亡率的替代性低成本益生菌治疗。