B-ALL cell lines (KOPN-8, MHH-CALL-4, Nalm-6, Nalm-6 GFP/Luc) showed a high CD19 expression (expressed in 95–100% of the cells, Figure 1a) and a modest expression of inhibitory ligands, being Gal-9 the most abundantly expressed (50–100%, Figure 1a). The gene discussed is CD19; the disease is acute lymphoblastic leukemia.