NCAM1 and rheumatoid arthritis: The cell proportion of PBMC in RA patients were further confirmed by flow cytometric analysis, which revealed 26.8% T cells, 22.8% CD3-CD56+NK cells, and 26.1% monocytes (22.8% CD16- monocytes and 3.3% CD16+ monocytes) in PBMC from RA patients (Supplementary Figure 3).