CD8+ TCR transgenic strains expressing public versus private TCR targeting the respiratory syncytial virus K^dM2_82-90 epitope demonstrate similar functional profiles

Our previous work has characterized the functional and clonotypic features of two respiratory syncytial virus (RSV) epitope-specific T cell responses in mice. Following single-cell sequencing, we selected T cell receptor sequences to represent both a public and a private clone specific for the dominant K ^dM2_82-90 epitope for the generation of T cell receptor transgenic (TCR Tg) mice. We evaluated cells from these TCR Tg strains for three major functions of CD8+ T cells: proliferation, cytokine production and cytolytic activity. In vitro comparisons of the functional characteristics of T cells from the newly-generated mice demonstrated many similarities in their responsiveness to cognate antigen stimulation. Cells from both TRBV13-1 (private) and TRBV13-2 (public) TCR Tg mice had similar affinity, and proliferated similarly in vitro in response to cognate antigen stimulation. When transferred to BALB/c mice, cells from both strains demonstrated extensive proliferation in mediastinal lymph nodes following RSV infection, with TRBV13-2 demonstrating better in vivo proliferation. Both strains similarly expressed cytokines and chemokines following stimulation, and had similar Granzyme B and perforin expression, however cells expressing TRBV13-1 demonstrated better cytolytic activity than TRBV13-2 cells. These new, well-characterized mouse strains provide new opportunities to study molecular mechanisms that control the phenotype and function of CD8+ T cell responses.