Flow cytometric immunophenotyping of lymphocytes of 4 B-CLL patients with an in-frame

IGK and IGL gene rearrangement. (A) CD19⁺ B lymphocytes of patient 3 express Igκ but not Igλ. Patient 8 (B) and patient 9 (C) express Igλ on CD19⁺ B lymphocytes, but no Igκ expression is detectable. (D) Patient 10 has low Igλ expression, but Igκ expression is absent.