Abstract 1407: Investigating the effect of an aged liver microenvironment on immune surveillance and predisposition to cancer

Abstract The incidence of liver cancer is increasing and there is an urgent need for new therapies and preventative strategies. Age is a major risk factor for liver cancer, the reasons for which are not well defined. One of the hallmarks of aging is immune dysfunction which affects liver homeostasis potentially making it prone to cancer. To understand the role of immune dysfunction in aging liver, we analyzed immune cells from young and old livers. As is reported before, in aged livers we observed an increase in CD101+PD1+CD8+ T cell population as well as an increase in an IFNγ+TNFα+ population suggesting an increase in T cell response in an aging liver. We next sought to understand the cause of T cell exhaustion in aged livers. Cell cluster analysis of the young (4-month-old) and old (22 month old) livers by scRNA seq revealed a cell population unique to the aged livers, showing increased expression of immune checkpoint ligands as well as tumor-initiating cell markers. We validated this data by flow cytometry. We next functionally probed the immune environment of aged liver, by testing the effect of cognate antigen expression in young and old hepatocytes on adoptively transferred activated P14 CD8+ T cells isolated from a young P14 mouse. Analysis of the ex vivo activated P14 CD8+ T cells from young and old antigen-expressing livers by flow cytometry and scRNA sequencing revealed increased exhaustion and cytokine-deficiency in old mice as compared to the young mice. This study explores the age-associated alterations in the immune cells in the liver, aiming to alter liver-resident immune cells and their metabolic states in a way that promotes anti-tumor immunity in an aging liver. Citation Format: Armin Aabish Gandhi, Filipe Araujo Hoffmann, Michael LaPorte II, Aaron Havas, Adarsh Rajesh, Andrew Davis, Marcos G. Teneche, Jessica Proulx, Susan Kaech, Peter D. Adams. Investigating the effect of an aged liver microenvironment on immune surveillance and predisposition to cancer​ [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1407.