R01AI167245

Regulation of LPS-Responses by ZBP1 - Project Summary

The goal of this proposal is investigation of the mechanism of ZBP1-mediated response to LPS and protection from bacterial infection that is provided by ZBP1. Our published and preliminary data characterize a novel noncanonical activation of caspase 8 in response to LPS, which results in the pyroptotic cell death in macrophages.

In further inquiry, we identified that the formation of the caspase 8 pro-death complex II, which assembles in response to LPS, is not dependent on TNFR1 as was widely accepted so far, but rather on TRIF, thus making TRIF a central component of this activation pathway. To reflect the requirement for TRIF in complex II formation and activation of caspase 8, we termed this new pyroptosis-inducing complex the "TRIFosome".

In further mechanistic inquiry, we found that the nucleic acid sensor, ZBP1, which thus far has been implicated only in viral infections, plays a significant role in the formation of the TRIFosome complex by shuttling RIPK1 to TRIF. The reliance of complex II formation on ZBP1 raised a question whether ZBP1 mediates inflammatory responses to LPS as well.

In support of this hypothesis, our preliminary data show that ZBP1 mediates LPS-induced inflammatory responses, thus providing rationale for further in vivo investigations of the role that ZBP1 might play in responses to LPS and Yersinia infection. To address whether ZBP1-mediated response to LPS provides protection from bacterial infection, we propose 2 aims.

In Aim 1, we will investigate ZBP1-mediated in vitro response to LPS using double knockout and gene-silencing approaches. We will use ZBP1-specific immunoprecipitation in order to determine the components of ZBP1-interactome. We will determine the contribution of ZBP1 to LPS-induced immune response, which will include elucidation of the specific role of ZBP1 in mediating TRIF-dependent and TRIF-independent responses. It will also include delineation of the role of ZBP1 in the RIPK1-specific response to LPS, including understanding the roles of the functional domains of ZBP1 in this pathway, analysis of the recruitment of ZBP1 into the endosomal TRIFosome complex, and characterization of the ZBP1-dependent changes in host response to bacterial infection in vivo.

In the second aim, we will capitalize on our preliminary findings and will further investigate how the kinetics of response to LPS that is conferred by ZBP1 confers sensitivity to LPS-induced toxicity in vivo, and whether this sensitivity provides protection from gram-negative infection in vivo. These studies will help establish the role of ZBP1 in host response to bacterial infection and will position ZBP1 at the cross-talk of different immune response pathways.

Trustees Of Tufts College

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 021111817 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 459% from $697,428 to $3,899,639.