CD80 and B-cell chronic lymphocytic leukemia: Profiling the surface molecules by FACS showed that GIFT4-CLL cells are CD23+, CD40+, CD80+, CD86+, MHCI+, and MHCII+, with enhanced expression of CD54 and down-regulation of CD27 and IL-4 receptor CD124 in comparison with control cytokine treatment (Fig. 1e).