Abstract: The present disclosure relates to multispecific molecules comprising a peptide-MHC complex and an immune cell antigen targeting moiety. Particular aspects relate to multimeric (e.g., dimeric) molecules comprising a peptide-MHC complex, an immune cell antigen targeting moiety, and a multimerization moiety. The disclosure further provides pharmaceutical compositions comprising the multispecific molecules, and methods of use of multispecific molecules in antigen-specific T cell activation, in inducing an antigen-specific immune response, and in therapeutic applications, as well as nucleic acids encoding the multispecific molecules, recombinant cells that express the multispecific molecules, and methods of producing the multispecific molecules.

Abstract: Provided herein are methods and compositions for assaying vaccinia virus-specific T cell responses in a sample from a subject undergoing treatment with an oncolytic vaccinia virus. The compositions comprise custom peptide pools from known immunogenic vaccinia virus epitopes in an HLA-agnostic format to profile peripheral CD8+T cell responses.

Abstract: Described is an autologous primary immune cell assay in which an individual's own blood cells may be functionally screened against individual antigens, e.g., T cell epitopes, of interest simultaneously without HLA haplotype-specific reagent. Antigen reactivities are linked to individual T cells using an oligonucleotide-tagging hashing tracking system, which is later deconvolved by single cell sequencing.