CD200 and B-cell chronic lymphocytic leukemia: In SMZL patients, CD200 was dim positive (40%-60%), in patients with HCL,CD200 was also bright positive (96% and 97%) and in patients with MCL CD200 was negative (1-10%); CD200 was significantly higher in CLL patients compared with the other B-cell chronic lymphoproliferative disorders (Fig. 4).