CLL-cell survival with or without NLCs. (A) Inhibition of CLL-cell survival on NLCs by BCMA-Fc but not BAFF-R:Fc. CLL B cells were cultured with (□) or without (▪) NLCs and 1 μg/mL control Ig. BCMA-Fc (▴) or BAFF-R:Fc (•) at 1 μg/mL was added to the wells of CLL B cells cultured with NLCs at day 0. Viability was subsequently determined for each time point, as indicated on the horizontal axis. Displayed is the mean percent viability ± SD (error bars) of samples from each of 5 patients. The percent viability of BCMA-Fc–treated cultures was significantly less than that of control Ig–treated cultures (^*P < .05; ^**P < .01; Bonferroni t test). (B) Enhanced CLL-cell survival with NLCs or rhBAFF or rhAPRIL. A total of 1 × 10⁶/mL isolated CD19⁺ CLL B cells was cultured alone (□), with 50 ng/mL rhBAFF (▴), 500 ng/mL rhAPRIL (•), both rhBAFF and rhAPRIL (○), or NLCs (▪) and evaluated over time. Displayed is the mean percent viability ± SD of samples from each of 3 patients. The percent viability of rhBAFF-treated CLL cells or rhAPRIL-treated CLL cells was significantly greater than that of control-treated CLL cells (^*P < .05; ^**P < .01; Bonferroni t test).