Although we cannot rule out the possibility that the Nivolumab gene signature is upregulated in RA due to dysregulation of other T cell pathway(s), our results still indicate that upregulated genes are PD1-responsive and therefore, the gene signature and the activity of T cells could be potentially down-modulated with a PD-1 pathway agonist therapeutic. Here, PDCD1 is linked to rheumatoid arthritis.