Serial section analysis of pseudofollicles in B-CLL lymph node (avidin-streptavidin-peroxidase staining with different combinations of mAbs).

In the same lymph node examined in Figure 6C-D, pseudofollicles contain numerous Ki-67 (ie, proliferating) cells (100 × magnification) (A). Few p27kip1⁺ cells are observed in a corresponding area on serial sections (100 × magnification) (B), whereas virtually all cells are intensely Bcl-2⁺ (200 × magnification) (C).