Article
作者: Kim, Dae Hee ; Tae, Nara ; Park, Sujeong ; Kang, Yeon-Woo ; Choi, Sun Shim ; Lee, Minji ; Lee, Kun-Joo ; Sohn, Joohyuk ; Moon, Dain ; Choi, Donghoon ; Song, Ha Won ; Yang, Jaehyuk ; Jeong, Siheon ; Park, Su-Hyung ; Hong, Da Hee ; Park, Yunji ; Im, Sun-Kyoung ; Oh, Youngsik ; Park, Uni ; Kim, Ji-Hae ; Lee, Seung-Woo ; Byun, Mi-Sun
Bispecific T cell engagers (TCEs) show promising clinical efficacy in blood tumors, but their application to solid tumors remains challenging. Here, we show that Fc-fused IL-7 (rhIL-7-hyFc) changes the intratumoral CD8 T cell landscape, enhancing the efficacy of TCE immunotherapy. rhIL-7-hyFc induces a dramatic increase in CD8 tumor-infiltrating lymphocytes (TILs) in various solid tumors, but the majority of these cells are PD-1-negative tumor non-responsive bystander T cells. However, they are non-exhausted and central memory-phenotype CD8 T cells with high T cell receptor (TCR)-recall capacity that can be triggered by tumor antigen-specific TCEs to acquire tumoricidal activity. Single-cell transcriptome analysis reveals that rhIL-7-hyFc-induced bystander CD8 TILs transform into cycling transitional T cells by TCE redirection with decreased memory markers and increased cytotoxic molecules. Notably, TCE treatment has no major effect on tumor-reactive CD8 TILs. Our results suggest that rhIL-7-hyFc treatment promotes the antitumor efficacy of TCE immunotherapy by increasing TCE-sensitive bystander CD8 TILs in solid tumors.