CD4 and rheumatoid arthritis: It was demonstrated in the results of immune infiltration analysis that both the RA and MN samples showed higher expression of various immune cells, including CD56 bright natural killer cell, central memory CD4 T cell, central memory CD8 T cell, gamma delta T cell, immature B cell, macrophage, myeloid-derived suppressor cell (MDSC), monocyte, natural killer cell, natural killer T cell, plasmacytoid dendritic cell, regulatory T cell, T follicular helper cell, type 1 T helper cell, type 2 T helper cell (Figure 3G,H).