CFU-Mk assay. Bone marrow cells (105) extracted from each mouse femur were cultured in collagen-based, serum-free medium for 7 days. Cultures were dried, fixed, and assayed for acetylcholinesterase activity. Colonies with 3 or more megakaryocytes were scored as CFU-Mk (Meg), and the rest were scored as nonmegakaryocyte colonies (non-Meg). (A) Average numbers of CFU-Mk from TG58 and TG74 compared with wild-type (WT) mice. (B) Average numbers of megakaryocytes in CFU-Mk colonies from Aurora-B/AIM-1 transgenic lines TG58 and TG74 compared with wild-type mice. Numbers in transgenic mice were approximately 40% greater than in wild-type mice (P < .01; Student t test). As shown, the average megakaryocyte number in a wild-type colony was 8.4. (C) Percentage of megakaryocyte colonies that had higher-than-average megakaryocyte number (8.4). Megakaryocyte colonies TG58 and TG74 had more cells than wild-type (P < .01; Student t test). Data presented are mean ± SD of 6 mice per experimental group, each assayed in duplicate.
