According to our previous studies,4, 28 the binding of Tim‐3 on Treg and Galectin‐9 promotes the function of Treg cells while inhibiting Th1 cells and CD4+T cells, which can be restored by blocking the Galectin‐9/Tim‐3 pathway in vitro experiments of CLL. Here, HAVCR2 is linked to B-cell chronic lymphocytic leukemia.