Figure 4. Retreatment of CLL Cells Surviving ALM CDC.

CLL cells were first treated with ALM and 10%NHS and the surviving viable intact cells were then isolated by density centrifugation. These cells were subsequently reacted in 10%NHS with ALM, OFA, or ALM + OFA and viable absolute cell counts were measured and normalized to the counts of cells treated with only 10%NHS. A: Retreatment of CLL cells with ALM and 10%NHS resulted in little additional cytotoxicity in most patients (median 7%)(p > 0.1) although some samples did show more CDC. The median %CDC was significantly higher for cells treated with OFA (32%)(p=0.01) or the combination of ALM and OFA (50%)(p=0.01). B: The cumulative cytotoxicity achieved by sequential treatment of CLL cells with ALM and 10%NHS followed by isolation of viable cells and treatment of these cells with ALM, OFA or ALM + OFA with 10%NHS. These data show that higher CDC was achieved using OFA than using ALM alone (p=0.01) and that the highest CDC was achieved with ALM + OFA (p=0.01). The median %CDC (represented by the horizontal bar in dot plots) and %cell lysis for each mAb treatment is shown in the box below the dot plots.