Figure 4

CD16- and CD16+ cells are the major reservoirs of OC precursors in HC and PsA patients, respectively. (a) 30 to 50% of MHCII+CD16+ cells are CD14+. Human peripheral blood mononuclear cells (PBMC) were isolated from the peripheral blood and stained with an antibody cocktail composed of MHCII-FITC, CD14-APC, CD16-PE, 7AAD. The gating strategy is sequentially illustrated from a to d. [a] PBMC were gated by FSC/SSC; [b] live cells were gated by 7AAD; [c] dot plot analysis of MHCII and CD16 expression on live cells; [d] the expression of CD14 on MHCII+CD16+ cells gated from c. Red line is the isotype control and blue line is staining from CD14-APC. The number shown in the histogram represents the frequency of CD14+ cells per total MHCII+CD16+ cells. [e] The relative percentage of CD14+CD16+ to MHCII+CD16+ cells. Sample shown here is the representative of 3 healthy controls (HC). (b) Human PBMC from HC and psoriatic arthritis (PsA) patients were isolated, stained with antibodies, and sterile sorted into three populations, MHCII+CD16-, MHCII+CD16^int, and MHCII+CD16+. Osteoclastogenesis was examined by osteoclast (OC) count after eight-day culture in the presence of receptor activator of nuclear factor kappa-B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) (MHCII+CD16-: purple, MHCII+CD16^int: turquoise, MHCII+CD16+: orange). Subject numbers 1 to 3 are HC and numbers 4 to 8 are PsA patients.