Project Grant F30AI203362

THE ROLE OF AIOLOS IN LUNG-RESIDENT CD8+ MEMORY T CELL PROGRAMMING. - PROJECT SUMMARY INFLUENZA A VIRUS (IAV) WAS RESPONSIBLE FOR HALF OF ALL PANDEMICS IN THE PAST CENTURY AND REMAINS A SIGNIFICANT PUBLIC HEALTH THREAT. IAV AND OTHER INFLUENZA VIRUS STRAINS INFECT ~40 MILLION PEOPLE ANNUALLY IN THE U.S., RESULTING IN OVER 600,000 HOSPITALIZATIONS SINCE 2024. CURRENT VACCINES PRIMARILY ELICIT NEUTRALIZING ANTIBODIES AGAINST MUTATION-PRONE EXTERNAL VIRAL PROTEINS, LIMITING LONG-TERM PROTECTION. LUNG-RESIDENT MEMORY CD8 T CELLS (TRM) ARE PROMISING TARGETS FOR IMPROVING DURABLE, CROSS-PROTECTIVE IMMUNITY AS THEY RECOGNIZE CONSERVED INTERNAL VIRAL ANTIGENS AND RAPIDLY RESPOND DUE TO THEIR LOCALIZATION. HOWEVER, THE MECHANISMS THAT GOVERN TRM DIFFERENTIATION AND MAINTENANCE REMAIN POORLY UNDERSTOOD. OUR PRELIMINARY DATA IDENTIFIED AIOLOS (IKZF3) AS A NOVEL CANDIDATE INDUCER OF TRM FORMATION. USING A TCR-TRANSGENIC (OT-I) ADOPTIVE TRANSFER MODEL, WE FOUND THAT AIOLOS-DEFICIENT (IKZF3-/-) MURINE CD8+ T CELLS EXHIBIT RESTRICTED ENTRY AND RETENTION IN THE LUNGS AFTER IAV INFECTION. ADDITIONALLY, OUR DATA SHOW THAT IKZF3-/- CD8+ T CELLS EXPRESS SIGNIFICANTLY MORE EOMES (A TRM REPRESSOR), LESS CD103 (A CANONICAL TRM MARKER), AND LESS TGFBR1 (A TRM PROMOTER). BASED ON THESE FINDINGS, WE HYPOTHESIZE THAT AIOLOS INDUCES LUNG-RESIDENT TRM FORMATION TO PROMOTE DURABLE IMMUNITY AGAINST IAV INFECTION. AIM 1 WILL DEFINE HOW AIOLOS INFLUENCES THE GENERATION, MAINTENANCE, AND PROTECTIVE CAPACITY OF LUNG- RESIDENT TRM. CONDITIONAL KNOCKOUT MURINE MODELS WILL BE USED TO ASSESS HOW AND WHEN AIOLOS DEFICIENCY AFFECTS POLYCLONAL TRM FORMATION. TO DETERMINE WHETHER AIOLOS AFFECTS THE CROSS-PROTECTIVE CAPACITY OF TRM, WE WILL UTILIZE A HETEROSUBTYPIC INFECTION MODEL AND MEASURE LUNG VIRAL TITER. AIM 2 WILL DETERMINE THE MECHANISM BY WHICH AIOLOS CONTRIBUTES TO TRM DIFFERENTIATION. WE WILL EVALUATE WHETHER THE TRM DEFECT IN IKZF3-/- CD8 T CELLS CAN BE RESCUED BY CONSTITUTIVE TGFBR1 EXPRESSION. TO IDENTIFY DIRECT AIOLOS GENE TARGETS, WE WILL USE CUT & RUN-SEQ. TO DETERMINE HOW AIOLOS AFFECTS GENE EXPRESSION AND CHROMATIN ACCESSIBILITY TO PROMOTE TRM DIFFERENTIATION, CITE- AND ATAC-SEQ WILL BE PERFORMED. MS. GAYATHRI DILEEPAN WILL PURSUE THESE RESEARCH AIMS AS PART OF A PERSONALIZED TRAINING PLAN DEVELOPED WITH HER SPONSOR AND MENTORSHIP TEAM TO ADVANCE HER CAREER AS A PHYSICIAN SCIENTIST TRAINEE. THE GOALS IN THIS TRAINING PLAN WILL LEAD MS. DILEEPAN TO PUBLISH AN INDEPENDENT RESEARCH PROJECT, DEVELOP EXPERTISE IN CELLULAR IMMUNOLOGY, MOLECULAR TECHNIQUES, AND BIOINFORMATICS, AND BECOME AN EFFECTIVE SCIENTIFIC COMMUNICATOR WHILE MAINTAINING CLINICAL INVOLVEMENT. HER RESEARCH WILL BE STRENGTHENED BY THE EXCEPTIONAL TRAINING ENVIRONMENT AT THE OHIO STATE UNIVERSITY AND THE DIVERSE EXPERTISE OF HER MENTORSHIP TEAM. ULTIMATELY, THIS PROJECT WILL DELINEATE THE NOVEL ROLE OF AIOLOS AS AN INDUCER OF LUNG- RESIDENT TRM FORMATION, HIGHLIGHT AIOLOS AS A THERAPEUTIC TARGET TO IMPROVE DURABLE VACCINE-GENERATED IMMUNITY AGAINST IAV INFECTION, AND EXPAND MS. DILEEPAN'S SCIENTIFIC PERSPECTIVE AND PROFESSIONAL NETWORK, POSITIONING HER FOR A SUCCESSFUL TRANSITION TO THE NEXT STAGE OF HER CAREER.