By extension, our findings imply that anti-PD-1/anti-PD-L1 therapy may activate HBV-specific, as well as global and bystander, CTLs in patients with OBI and reactivate hepatitis B. In this context, it is now recognized that CHB patients subjected to therapy with immune check inhibitors targeting PD-1/PD-L1 or CTLA-4 are at a risk of reactivation of HBV infection (He et al., 2021; Ding et al., 2022). Here, CTLA4 is linked to hepatitis B virus infection.