Figure 3

Percentage of immunoglobulin (Ig) expression on IL-10-producing B peripheral-cell subtype in patients with primary Sjögren's syndrome (pSS). CD19⁺ blood B cells were obtained by positive selection with microbeads. (A) Representative unstained and permeabilized sample of peripheral blood mononuclear cells (autofluorescence control). (B) phycoerythrin (PE)-labeled-anti rat-IL-10 IgG isotype control. (C-E) IgG₁-fluorescein isothiocyanate (FITC)/IgG₁-PE/CD45-PeCy5 mouse IgG₁, k isotype controls (BD Tritest™, BD Biosciences). (F) Representative contour plot of CD19⁺ B cells. An electronic gate was made for CD38^hi cells. (G) From the gate F CD19⁺⁄CD38^hi/IgM⁺ cells were determined. (H) From the latter CD19⁺⁄CD38^hi⁄IgM⁺⁄IL-10⁺ cells were defined. A total of 50,000 to 100,000 events were recorded for each sample before any gate setting, and were analyzed with the CellQuestPro software (BD Biosciences). Bar graphs show percentage of (I) CD19⁺⁄CD38^hi⁄IgM⁺⁄IL-10⁺ (J) CD19⁺⁄CD38^hi⁄IgG⁺⁄IL-10⁺, and (K) CD19⁺⁄CD38^hi⁄IgA⁺⁄IL-10⁺ cells. (I-K) Results are expressed as median, 10^th, 25^th, 75^th, and 90^th percentiles. *P < 0.05. APC, allophycocyanine.