- Graft-versus-host disease illustrates differential activation depending on clinical subtype: acute GvHD involves integrated Th1, Th17, and Th2 responses, whereas chronic lichenoid GvHD demonstrates dominant Th1/Th17 involvement, notably mediated by IFN-γ and cytotoxic CD8+ T cells. The gene discussed is CD8A; the disease is graft versus host disease.