Fig. 2

JBCs are detected among IgM⁺ and IgG⁺ B cells, with the majority being non-class-switched. PBMCs from healthy controls (top) or Jo-1 ARS (bottom) patients were stained and analyzed using flow cytometry. a Live, CD19⁺ CD5⁻ CD14⁻ CD16⁻ cells were gated and anti-GST secondary antibody discriminated between Jo-1/GST-binding (Jo-1⁺) and non-JBCs (Jo-1⁻) B cells. b Cells were further gated on IgM versus IgG expression by non-JBC and JBC. Representative plots from healthy control and Jo-1 ARS donors are shown. c–f Flow cytometry identifies the indicated populations among n = 5 stable Jo-1 ARS (triangles), n = 5 active Jo-1 ARS (circles), and n = 8 healthy controls (diamonds). c JBCs were identified as in panel a and their frequency of total B cells was determined. d The IgM⁺ or IgG⁺ cell frequency (gated as in panel b) of JBCs (gated as in panel a) is shown for Jo-1 ARS patients that had > 20 JBC events (n = 6). e The frequency of JBCs within IgM⁺ (e) or IgG⁺ (f) B cells is shown. Individual donors are plotted, and bars represent the mean ± SD. p values were determined using the Mann-Whitney U test, and are indicated on each panel