Method to Assess Immunosenescent CD8⁺ T Cells in Respiratory Viral Infections

Immunosenescence is a well-characterized phenomenon that occurs with increasing age in all immune and somatic cells. In order to best study immunosenescence, it is imperative to develop methods to accurately identify immunosenescent cells. Elderly patients are known to have impaired immune responses to respiratory viruses, and it is hypothesized that this is due, in part, to immunosenescent, terminally exhausted CD8⁺ T cells. To test this hypothesis, we developed an aged mouse model and a flow cytometry protocol using the Cytek^® Aurora to assess the CD8⁺ T-cell response during respiratory viral infection and identify immunosenescent CD8⁺ T cells. This protocol and our aged mouse model have great potential to be incredibly valuable for future studies elucidating how to rejuvenate and possibly reverse immunosenescent CD8⁺ T cells, which could improve the immune response to respiratory viruses in this at-risk population.