CD40 and B-cell chronic lymphocytic leukemia: Because CpG 2006 has been reported to contribute to chemoresistance to bendamustine and fludarabine in CLL cells when combined with CD40 ligation in bone marrow stromal coculture experiments [23], CpG ODNs may be best utilized in combination with immune-based therapies that could benefit from the enhanced costimuatory molecule expression on the CLL cells, along with enhanced activation of other immune cells, rather than chemotherapy based treatments.