The majority of SF CD11c+ myeloid cells, unlike PB, were encompassed by cluster 17 (45.6% ± 4.4) and cluster 12 (11.1% ± 2.4), expressing neither CD14 nor CD16 with higher HLA-DR levels, likely representing myeloid dendritic cells (mDCs) (53.0 ± 5.0% of SF CD11c + myeloid cells vs 12.9 ± 0.9% HC PB, 15.7 ± 1.0% JIA PB, P < 0.0001, Fig. 2E). Here, FCGR3A is linked to juvenile idiopathic arthritis.