CD19 and Miyoshi myopathy: The increase in CD19int FCShigh cells was accompanied by a marked decrease in CD19- non-B cells in MM patients (58.6 ± 3.3%) compared to controls (87.7 ± 2.5%; P < 0.0001), whereas the percentages of CD19+ B cells did not differ significantly between MM patients (9.0 ± 1.0%) and controls (6.8 ± 2.2%; P = 0.3405).