G1 phase changes from unstimulated (US) and stimulated (S) B-CLL cells. G1 phase changes (mean percentages ± SD) from unstimulated (US) and stimulated (S) B-CLL cells were evaluated using the AO technique after 48 hours of culture in (A) IgVH unmutated and (B) IgVH mutated samples. Representative experiment obtained from an IgVH unmutated patient is shown in the box.