R01AI158247

Control of Intestinal Innate Immunity by the Commensal Microbiota in a Model Host - Abstract/Project Summary

Microbes interact with the intestinal epithelium in ways that modulate susceptibility to infection, malnutrition, and predisposition to chronic metabolic diseases such as obesity and diabetes. However, the host signaling pathways utilized by microbes to promote health and disease are poorly understood. The powerful genetic tools provided by the model arthropod Drosophila melanogaster have enabled many discoveries that form the basis of our modern understanding of innate immunity.

Here, we propose to exploit the Drosophila melanogaster model to define the host signaling pathways that detect intestinal microbes and orchestrate the innate immune response of the intestinal epithelium. Drosophila intestinal stem cells, enterocytes, and enteroendocrine cells (EECs) carry out functions similar to those of the mammalian intestine. EECs, which constitute 5-10% of cells in the intestinal epithelium, secrete enteroendocrine peptides (EEPs) that modulate host metabolic functions such as insulin signaling, satiety, and intestinal contractions.

We have identified a subset of EECs that responds uniquely to the microbial fermentation product acetate by activating innate immune signaling through the TNF-like immunodeficiency (IMD) pathway. In these EECs, IMD signaling increases transcription of the genes encoding EEPs. These EEPs, in turn, coordinate the response of the diverse cell types in the intestine to microbes.

Here, we investigate the mechanism by which microbes activate the intestinal innate immune response and the ultimate impact of this regulatory pathway on susceptibility to infection. In this proposal, we will investigate the role of chromatin remodeling in acetate-mediated IMD signaling, the contribution of peptidoglycan to intestinal IMD signaling, the role of EEPs as cytokines, and finally the cell-specific roles of EEPs in modulating susceptibility to intestinal infection.

The overarching objective of this research is to uncover novel paradigms of the intestinal innate immune response to microbes with the goal of informing therapies that modify nutrient utilization in malnutrition, chronic metabolic diseases, and susceptibility to intestinal infection.

Children's Hospital Corporation

TO ASSIST PUBLIC AND PRIVATE NONPROFIT INSTITUTIONS AND INDIVIDUALS TO ESTABLISH, EXPAND AND IMPROVE BIOMEDICAL RESEARCH AND RESEARCH TRAINING IN INFECTIOUS DISEASES AND RELATED AREAS, TO CONDUCT DEVELOPMENTAL RESEARCH, TO PRODUCE AND TEST RESEARCH MATERIALS. TO ASSIST PUBLIC, PRIVATE AND COMMERCIAL INSTITUTIONS TO CONDUCT DEVELOPMENTAL RESEARCH, TO PRODUCE AND TEST RESEARCH MATERIALS, TO PROVIDE RESEARCH SERVICES AS REQUIRED BY THE AGENCY FOR PROGRAMS IN INFECTIOUS DISEASES, AND CONTROLLING DISEASE CAUSED BY INFECTIOUS OR PARASITIC AGENTS, ALLERGIC AND IMMUNOLOGIC DISEASES AND RELATED AREAS. PROJECTS RANGE FROM STUDIES OF MICROBIAL PHYSIOLOGY AND ANTIGENIC STRUCTURE TO COLLABORATIVE TRIALS OF EXPERIMENTAL DRUGS AND VACCINES, MECHANISMS OF RESISTANCE TO ANTIBIOTICS AS WELL AS RESEARCH DEALING WITH EPIDEMIOLOGICAL OBSERVATIONS IN HOSPITALIZED PATIENTS OR COMMUNITY POPULATIONS AND PROGRESS IN ALLERGIC AND IMMUNOLOGIC DISEASES. BECAUSE OF THIS DUAL FOCUS, THE PROGRAM ENCOMPASSES BOTH BASIC RESEARCH AND CLINICAL RESEARCH. SMALL BUSINESS INNOVATION RESEARCH (SBIR) PROGRAM EXPANDS AND IMPROVES PRIVATE SECTOR PARTICIPATION IN BIOMEDICAL RESEARCH. THE SBIR PROGRAM INTENDS TO INCREASE AND FACILITATE PRIVATE SECTOR COMMERCIALIZATION OF INNOVATIONS DERIVED FROM FEDERAL RESEARCH AND DEVELOPMENT, TO INCREASE SMALL BUSINESS PARTICIPATION IN FEDERAL RESEARCH AND DEVELOPMENT, AND TO FOSTER AND ENCOURAGE PARTICIPATION OF SOCIALLY AND ECONOMICALLY DISADVANTAGED SMALL BUSINESS CONCERNS AND WOMEN-OWNED SMALL BUSINESS CONCERNS IN TECHNOLOGICAL INNOVATION. THE SMALL BUSINESS TECHNOLOGY TRANSFER (STTR) PROGRAM STIMULATES AND FOSTERS SCIENTIFIC AND TECHNOLOGICAL INNOVATION THROUGH COOPERATIVE RESEARCH AND DEVELOPMENT CARRIED OUT BETWEEN SMALL BUSINESS CONCERNS AND RESEARCH INSTITUTIONS, TO FOSTER TECHNOLOGY TRANSFER BETWEEN SMALL BUSINESS CONCERNS AND RESEARCH INSTITUTIONS, TO INCREASE PRIVATE SECTOR COMMERCIALIZATION OF INNOVATIONS DERIVED FROM FEDERAL RESEARCH AND DEVELOPMENT, AND TO FOSTER AND ENCOURAGE PARTICIPATION OF SOCIALLY AND ECONOMICALLY DISADVANTAGED SMALL BUSINESS CONCERNS AND WOMEN-OWNED SMALL BUSINESS CONCERNS IN TECHNOLOGICAL INNOVATION. RESEARCH CAREER DEVELOPMENT AWARDS SUPPORT THE DEVELOPMENT OF SCIENTISTS DURING THE FORMATIVE STAGES OF THEIR CAREERS. INDIVIDUAL NATIONAL RESEARCH SERVICE AWARDS (NRSAS) ARE MADE DIRECTLY TO APPROVE APPLICANTS FOR RESEARCH TRAINING IN SPECIFIED BIOMEDICAL SHORTAGE AREAS. IN ADDITION, INSTITUTIONAL NATIONAL RESEARCH SERVICE AWARDS ARE MADE TO ENABLE INSTITUTIONS TO SELECT AND MAKE AWARDS TO INDIVIDUALS TO RECEIVE TRAINING UNDER THE AEGIS OF THEIR INSTITUTIONAL PROGRAM.

93.855 - Allergy and Infectious Diseases Research

National Institute of Allergy and Infectious Diseases (NIAID) [HHS - NIH]

Boston, Massachusetts 021155724 United States

Single Zip Code

NIH Research Project Grant (Parent R01 Clinical Trial Not Allowed) (PA-20-185)

Amendment Since initial award the total obligations have increased 388% from $719,763 to $3,511,902.