IFNG and cancer: Bispecific CD3-HAC expectedly induced the cytotoxic T lacking PD-L1, although the killing effect remains modest within the first 10 h of interaction (Fig. 2a), the concentrated CD3-HAC protein can boost the tumor infiltrating lymphocyte primarily, and consequently increase the expression of PD-L1 on cancer cells driven by IFN-γ, which represents a reinforced positive feedback loop in the long run.