T Cell Differentiation in Tissue Microenvironments - ABSTRACT Support is requested for a Keystone Symposia conference entitled T Cell Differentiation in Tissue Microenvironments, organized by Drs. Greg Delgoffe, Amanda Lund, Nikhil Joshi and Laura Mackay. The conference will be held in Vancouver, British Columbia, Canada from February 2–6, 2025. Normal and pathological immune responses function across tissues that harbor unique metabolic, environmental, and cellular microenvironments. Therefore, the mechanisms that recruit and activate leukocytes, define their interstitial function and survival, or promote their retention in particular tissues are crucial to understanding how to boost, redirect, or restrict immune responses across the spectrum of health and disease. While the topic of tissue specific immunity has been touched on in other meetings, this is the first conference to integrate discussion across diverse tissues and disease contexts. The program will cover how various tissues shape the immune responses that are generated within, while highlighting emerging technologies that are enabling advancements in this field. The speaker lineup will attract a vast array of multidisciplinary scientists thinking about T cell differentiation in tissues in the context of diverse diseases, such as cancer, autoimmunity, and infection. In addition, as a joint meeting with the Keystone Symposia conference on Innate Immune Memory: Mechanisms and Consequences, the intersections of audiences and researchers will enable dynamic crosstalk, cross-disciplinary insights and collaboration towards understanding the interconnectedness of innate and adaptive immunity, and interplay with tissue microenvironments.