Fig. 7

A lower frequency of JBCs acquire a plasmablast phenotype following stimulation in vitro compared to non-JBCs from the same Jo-1 ARS patients. PBMCs from n = 5 Jo-1 ARS patients with active disease were polyclonally stimulated as in the “Methods” section. Cultured cells from n=40-60 wells per patient were harvested on day 6 and stained for flow cytometry analysis. a CD24 and CD38 expression is shown in representative flow plots derived from a single well of stimulated PBMCs. Comparison of mean frequencies of b CD38^hi CD24⁻ B lymphocytes or c CD38^hi CD24^mid B lymphocytes between JBC and non-JBC populations. Significant differences between IgM⁺ JBC and IgM⁺ non-JBC or IgM⁻ JBC and IgM⁻ non-JBC populations as calculated using Mann-Whitney U test are indicated. The data are represented as the mean for each population within a given stimulation, and the bars indicate the mean ± SD