The mean corrected synovial fluid level of anti-CCP (IgG) was 0.17 ± 0.08 × 105 RU/g per L. The Spearman's rho analysis showed that there was a highly positive association between the expressions of GRP78 of plasma cells from synovial fluid and the corrected synovial fluid levels of anti-CCP (IgG) in inflamed RA peripheral joints (Figure 4). The gene discussed is HSPA5; the disease is rheumatoid arthritis.