In addition, although HMGB1, abundantly released from CD44-high leukemia cells after ULMW-HA stimulation can not directly kill leukemia cells, it should act as one of proinflammatory DAMPs and stimulate to secrete ULMW-HA from mesenchymal cells, which in turn could induce cell death of CD44-high leukemia cells with a release of HMGB1, thus leading to the formation of cell death-inducing positive feedback loop for leukemia cells at the site of infection and inflammation. Here, CD44 is linked to infection.