CD19 and Miyoshi myopathy: The percentages of CD19+CD24hiCD38hi Bregs in PBMCs of RRMM patients were significantly higher in comparison to HVs (median = 3.58%; range = 0%–14.92%; p = 0.0006), Ps patients (median = 2.55%; range = 0.1%–14.86%; p < 0.0001), and PBMCs of MM patients (median = 1.32%; range = 0.54%-4.69%; p = 0.0004) (Figure 2C).