T cell receptor-engineered T cells targeting the TP53R248Q neoantigen elicit antitumor effects in human cancer models

Malignant tumors with TP53 mutations exhibit poor therapeutic outcomes and high recurrence rates. T cell receptor (TCR)-based T cell therapy shows great promise for targeting intracellular cancer neoantigens. However, the immunogenic potential of TP53 hotspot mutations remain poorly characterized. Here, we identify a immunogenic neoantigen derived from the recurrent TP53R248Q mutation, presented by the prevalent Human Leukocyte Antigen (HLA)-A*11:01 allele. Additionally, we isolated a TP53R248Q reactive TCR that specifically recognize the TP53R248Q mutation without any discernable cross-activity to cognate wild-type TP53 or other TP53 mutants at the same codon position. Functional characterization revealed that TP53R248Q TCR-T cells exhibited selectively cytotoxicity against tumor cells expressing both TP53R248Q mutation and HLA-A*11:01 in vitro. Importantly, the adoptive transfer of TP53R248Q TCR-T cells exhibited significant anti-tumor activity in a clinically relevant patient-derived xenograft (PDX) model engrafted with TP53R248Q/HLA-A*11:01 positive human tumor tissues. Collectively, our study validates the immunogenicity of the TP53R248Q hotspot mutation and provides a TCR with high therapeutic potential for the development of T cell therapies targeting TP53R248Q/HLA-A*11:01 positive cancers.