Spatial, temporal and molecular dynamics of swine influenza virus-specific CD8 tissue resident memory cells

We have defined naïve, central memory, effector memory and terminally differentiated porcine CD8 T cells, using CD45RA and CCR7 mAbs. We analyzed the phenotype of CD8 T cells specific for three influenza nucleoprotein (NP) epitopes using tetramers after influenza infection or immunization in lymphoid and respiratory tissues. The hierarchy of response to the three epitopes changes during the response in different tissues. Most NP-specific CD8 T cells in broncho-alveolar lavage (BAL) and lung are tissue resident memory cells (TRM), that express CD69 and have an effector memory or terminally differentiated phenotype. NP-specific cells isolated from BAL express genes characteristic of TRM, but gene expression differs at 7, 21 and 63 days post infection. The frequency of NP-specific cells declines over 63 days in all tissues but is best maintained in BAL. The pig is a powerful model for understanding how best to induce and harness local immunity. RNA-seq of influenza specific FAC-sorted T cells