Immunocytologic staining of CCR4 in blood smears.

Routine blood smears obtained from 4 patients with ATL (A-D) were stained for CCR4 as described in “Materials and methods.” Leukemic cells are positive (A, B, C) or negative (D) for CCR4. No staining was seen by an isotype-matched control mouse IgG (not shown).The slides were counterstained by hematoxylin and the original magnification was × 1000.