Abstract
A method of cold-shock synchronization of immature granulocytic cells from peripheral blood or bone marrow is described. It is shown that this method provides an increased yield of early metaphases and offers advantages over others currently employed. The peaks of mitotic activity following the cold-shock treatment differ for patients with acute non-lymphoblastic leukemia (ANLL) and patients with chronic myeloid leukemia (CML) by an interval of 2 h. This method is considered to be suitable for routine cytogenetic studies on hematological patients.