CD74 induces IL-8 and Bcl-2 expression in CLL B cells. (A,C) Cells were incubated in the presence or absence of anti-CD74 antibody, Id2, a control antibody or MIF for 18 h. (A,C) RNA was purified and levels of IL-8, Bcl-2 and actin mRNA were analyzed. The results presented are representative of 7 early-stage and 5 advanced-stage B-CLL patients. (B) ) Cells’ conditioned medium was collected and their IL-8 levels were analyzed by ELISA. The results presented are representative of 3 independent experiments.