Xiaojing Chen, Zhiyuan Mao, E. Motunrayo Kolawole, Margherita Persechino, Kevin M. Jude, Masato Ogishi, Kelvin C. Mo, Jami McLaughlin, Donghui Cheng, Xinyu Xiang, Xinbo Yang, Caitlin Gee, Shiqin Liu, Aerin Yang, Matthias Obenaus, Nan Wang, Miyako Noguchi, Tanya Stoyanova, John K. Lee, Zinaida Good, Naomi R. Latorraca, Brian D. Evavold, OwenN Witte, K. Christopher Garcia
T cells are often weakly responsive to tumor self-antigens because of central tolerance, constraining their ability to eliminate tumors. We exploited mechanical force to engineer a weakly reactive T cell receptor (TCR) specific for a nonmutated tumor-associated antigen (TAA), prostatic acid phosphatase (PAP). We identified a catch-bonding "hotspot" whose mutation enhanced T cell activity by increasing TCR-pMHC (peptide-major histocompatibility complex) bond lifetime while preserving physiological affinities and antigen fine specificities. T cells expressing these engineered TCRs showed vastly superior expansion in the tumor, effector phenotypes, and tumor elimination. Crystal structures and molecular dynamics simulations revealed a single amino acid mutation at the catch-bond hotspot primes the TCR for peptide interaction through water reorganization at the TCR-pMHC interface. Catch-bond engineering is a viable biophysically based strategy for transforming tolerized antitumor T cells into potent TCR-T cell therapy killers.