CD8A and rheumatoid arthritis: The results of enrichment showed that most of the DEGs were involved in cellular response to cytokine stimulus (GO:0071345), cellular response to interferon-gamma (GO:0071346), inflammatory response (GO:0006954), cytokine-mediated signaling pathway (GO:0019221), abnormal macrophage physiology (MP:0002451), decreased CD8-positive, alpha–beta T cell number (MP:0008079), increased CD4-positive, alpha beta T cell number (MP:0008074), and also pathways including rheumatoid arthritis, cytokine–cytokine receptor interaction and, chemokine signaling pathway (Fig. 3).