Therefore, our finding that IL-6-stimulated CD4+ T cells from CLL patients displayed a higher ratio of p-STAT3, a pro-Th17 factor, relative to p-STAT1, an inhibitory Th17 factor, than CD4 + T cells from healthy subjects (Fig. 7), raises the possibility that CD4+ T cells from CLL patients, or a subset of CLL patients, are “primed” to differentiate along the Th17 lineage in response to activation signals. Here, IL6 is linked to B-cell chronic lymphocytic leukemia.