To investigate the anti-tumor effect of bintrafusp alfa in the PBMC humanized NSG-β2m−/− mouse model, we first utilized the HTB-1 cell line, which is an HLA-A2+ human bladder transitional cell carcinoma line that expresses high levels of PD-L1 (Supplemental Figure 1). The gene discussed is CD274; the disease is bladder transitional cell carcinoma.