Efficacy of CD22-targeted liposomes in a xenograft model of the disseminated Daudi human B lymphoma. (A) Top panel shows timeline for the in vivo efficacy study. Bottom panel: tumor-bearing mice that received PBS (untreated, n = 10), dox-loaded naked liposomes (n = 8), or ^BPCNeuAc liposomes (n = 8) containing 2% or 5% ^BPCNeuAc ligands were monitored for the onset of hind-leg paralysis for up to 100 days. Survival rate is presented in a Kaplan-Meier plot with indication of numbers of long-term survivor animals. (B) Estimation of residual Daudi lymphoma cells in the bone marrow. Shown are histograms of bone marrow cells isolated from tumor-bearing mice followed by staining with isotype (solid) or anti–human CD19 (line) antibodies to identify infiltrated Daudi cells. Shown are results from 1 of 3 representative mice that received the indicated treatment. Percentages of lymphoid gated CD19⁺ Daudi cells in the bone marrow are indicated. N.D. (not detected) refers to less than a 0.4% background observed for an IgG isotype control.