Triggering co-stimulation directly in melanoma tumor fragments drives CD8⁺tumor-infiltrating lymphocyte expansion with improved effector-memory properties

Abstract

TIL from solid tumors can express activation/co-stimulatory molecules like 4-1BB/CD137, a sign of recent antigenic stimulation in the tumor microenvironment (TME). This activated state can be exploited <i>ex vivo</i> to enhance the expansion of tumor-reactive CD8⁺ TIL for adoptive cell therapy through direct addition of immunomodulators to tumor fragments in culture.