PRF1 and oral lichen planus: To overcome this, our study focused directly on the immune component by assessing CD4+ and CD8+ T cell activation, TNF-α and IFN-γ secretion, and expression of cytotoxic molecules such as Perforin and Granzyme B. These immune markers are central to the pathogenesis of both OLP and oGVHD and provide a targeted framework for assessing the immunomodulatory potential of candidate therapies like CAN296.