Figure 4(a) shows the composition of immune cells in 23 RA samples and 16 normal samples. Wilcoxon test was conducted to determine whether there was a significant difference in immune cell infiltration between RA and HC samples. In violin plot (Figure 4(b)), it was revealed that memory B cells, plasma cells, CD8 T cells, activated CD4 memory T cells, T cells follicular helper, monocytes, and macrophages M1 were abundant in RA synovial membrane. This evidence concerns the gene CD4 and rheumatoid arthritis.