To further explore the ability of CLL Mo-DCs to alter the polarization of CD4+ T-cells toward Th1 or Th2 differentiation, we determined the percentage of IFN-γ (Th1-type)- and IL-4 (Th2-type)-producing cells by intracellular cytokine staining. This evidence concerns the gene IL4 and B-cell chronic lymphocytic leukemia.