B2M and leukemia: A 2-week course of treatment with 9AA (150 μg/mouse/day, a 14-day infusion), a 4-week course of treatment with Campath-1H (100 μg/mouse, weekly), and the combination of 9AA and Campath-1H manifested therapeutic efficacy as assessed by demonstration both of reduced serum levels of sIL-2Rα and β2μ and prolongation of survival of the leukemia-bearing mice (Figure 5).