Sepsis is characterized by a disseminated infection, resulting in a hyperinflammatory state, followed by prolonged immunoparalysis which is characterized by severe transient lymphopenia and long-lasting immunological dysregulation.
Our lab focus on naïve and memory CD8 T cell responses after acute infections and/or vaccinations. Upon cognate antigen-encounter naïve Ag-specific CD8 T cells undergo proliferative expansion in numbers and differentiate into effector cells that contribute to pathogen clearance. Thus, the status of naïve CD8 T cell compartment can determine the ability of the host to respond to newly encountered infections.
Sepsis induces rapid and vigorous apoptosis of naïve (Ag-non experienced CD11alow/CD8#913;high CD8 or CD11alow/CD49dlow CD4 T cells) T cells creating a lymphopenic environment supporting homeostatic proliferation (HP) of T cells that survive early ‘cytokine storm’ phase of sepsis. As a consequence of HP and in response to microbes that evoke sepsis, numerical recovery of T cell compartment is accompanied by phenotypic/functional changes (memory-like T cells) on a sizeable fraction of T cells. Sepsis can induce ‘holes’ in the T cell repertoire further contributing to overall changes in the composition of T cell pools, making their subsequent T cell responses to newly encountered pathogens potentially impaired.
One of my projects will be to further delineate sepsis-induced long-lasting functional, epigenetic, and transcriptomic changes in naïve CD8 T cells using state-of-the-art techniques and models readily available in the lab.
Sjaastad FV, Jensen IJ, Berton RR, Badovinac VP, Griffith TS. Inducing Experimental Polymicrobial Sepsis by Cecal Ligation and Puncture. Curr Protoc Immunol. 2020 Dec;131(1):e110. doi: 10.1002/cpim.110. PMID: 33027848; PMCID: PMC7747468.
Cutting Edge: Antitumor Immunity by Pathogen-Specific CD8 T Cells in the Absence of Cognate Antigen Recognition. Derek B. Danahy, Roger R. Berton and Vladimir P. Badovinac
Honors & Awards
- Wallace fellowship - 2021