A therapeutic regimen using neoantigen-specific TCR-T cells for HLA-A*2402-positive solid tumors.

The adoptive transfer of TCR-T cells specific to neoantigens preferentially exhibits potent cytotoxicity to tumor cells and has shown promising efficacy in various preclinical human cancers. In this study, we first identified a functional TCR, Tcr-1, which selectively recognized the SYT-SSX fusion neoantigen shared by most synovial sarcomas. Engineered T-cell expressing Tcr-1 (Tcr-T1) demonstrated HLA-A*2402-restricted, antigen-specific anti-tumoral efficacy against synovial sarcoma cells, both in vitro and in vivo. Furthermore, to extend its application, we developed a cooperative therapeutic modality, in which exogenous SYT-SSX fusion neoantigen was loaded into stimuli-responsive nanoparticles (NPs) formed by mPEG-PVGLIG-PCL copolymers (Neo-AgNPs) for tumor targeting delivery. As expected, Neo-AgNPs were proven to have great tumor penetration and local release. In situ, the modification was able to direct engineered Tcr-T1 against other HLA-A*2402-positive malignant cancer cell lines with significant antigen-specific cytotoxicity despite their inherent mutation profiles. With these favorable data, our established cooperative therapeutic modality has great potential for further clinical investigation and provides new insight for future TCR-T cell therapy development.