So far, HVEM has only been reported once as a co-stimulatory domain in CAR-T cells, with HVEM G2 CAR-T cells exhibiting enhanced anti-tumor cytotoxicity and pro-inflammatory cytokine production (e.g., IL-2, TNF-α, and IFN-γ)) as compared to control CD28 or 4-1BB G2 CAR-T cells [119]. The gene discussed is IFNG; the disease is neoplasm.