Complement-mediated lysis correlates with the intensity of CD20 expression.

(A) The mean fluorescence intensity of CD20 was plotted against the relative lysis obtained in the presence of rituximab and complement for each of the 33 B-CLL and 5 PLL patients shown in Figure 2. (B) The number of molecules per cell measured for 14 B-CLL/PLL patients was plotted against the percentage relative lysis for the same patients. The results of the statistical analysis are shown in each plot.