TCRVβ repertoire analysis by flow cytometry. (A) Expression of TCRVβ in PBMCs of a representative WM patient (patient no. 10) after cells were stained with a panel of TCRVβ antibodies from the Beta Mark kit and anti–CD3-ECD. (B) Percentage of CD3⁺ T cells expressing the TCRVβ of patient no. 10 compared with the mean ± 3 SD of the age-matched normal range.