Given the extent to which TCL1A has been implicated in several human B cell CLLs [78,116], Dilillo et al. tested whether TCL1A expression is correlated with IL-10 expression and, using samples from 52 patients with overt CLL, found that TCL1A expression positively correlated with IL-10 expression. Here, IL10 is linked to B-cell chronic lymphocytic leukemia.