CD5 and B-cell chronic lymphocytic leukemia: Indeed, TCL1 mice expressing IgM mainly displayed IGHV11-2, IGHV12-3, and IGHV1-55, which are the most commonly used IGHVs in the restricted repertoires exhibited by normal and autoimmune B-1 cells and by CLL-like murine CD5+ B cells (44, 45).