Since no information is available regarding the expression of K+ channels in CD5+CD19+ CLL B cells in this model, we first evaluated the expression level of Kv1.3 using a FITC-labelled antibody against an extracellular epitope of the protein (Fig. 1d, e), as described e.g. in [21]. Here, CD19 is linked to B-cell chronic lymphocytic leukemia.