CXCL12 and B-cell chronic lymphocytic leukemia: By contrast however, ABL activity did not appear to play a controlling role in the shape-change and motility induced by chemokine: Although the magnitude of CXCL12-induced cell shape-change was changed in the presence of imatinib, significant cell-elongation was present when compared with imatinib-treated cells not exposed to chemokine, and the proportion of cells that showed F-actin polarisation was identical for chemokine-treated CLL lymphocytes irrespective of the presence of imatinib (66% vs. 62% p = ns Chi Squared test).