The focus of the SpellmanGray work group over the past year has been upon the generation of materials, tools, and data for the purpose of aiding and supporting the research and findings of the entire multi-team collaboration endeavoring to identify antigenic targets for breast cancer-infiltrating T cells. Our team has achieved a number of accomplishments over the current funding year. We have characterized immunogenic peptides from a collection of MHC-I-bound epitopes eluted from the cell surface of several breast cancer cell lines. A computational pipeline was also developed to identify the sequence of the complete TCR heterodimer, working synergistically with data collected following single-cell emulsion RT-PCR. Additional modifications were made to our epitope discovery workflow to increase efficacy of transcript and neoantigen candidate prioritization for future research, and strides are being made in development of a personalized T cell-based protocol for identification of T cell-activating epitopes.