Abstract
Anti-CD8 immunoPET facilitates non-invasive, whole-body visualization of immune responses, and syngeneic preclinical models are a crucial tool for studying tumor infiltration of T cells in response to cancer therapies. This study characterized longitudinal CD8(+) T cell responses in an orthotopic mouse model of breast cancer treated with radiation and anti-CTLA4 by immunohistochemistry and anti-CD8 immunoPET, confirming an early but heterogeneous response induced by combination treatment that is detectable by imaging.