PHA-induced colony formation in acute non-lymphocytic and chronic myeloid leukemia

Abstract

A method which has previously been introduced for growing colonies in vitro from T-lymphocytic cells in normal subjects, has been applied to studying the growth of colonies from the bone marrow and blood of patients with acute non-lymphocytic leukemia and chronic myeloid leukemia. The technique consists of an underlayer of agar containing irradiated leukocytes and a liquid overlayer containing PHA. In leukemic patients, the assay permitted the formation of T-lymphocytic as well as leukemic colonies. Removal of the E-rosette forming cells before culture resulted in the appearance of mainly leukemic colonies. Cytogenetic analysis demonstrated the presence of the acquired karyotypic changes characteristic of the leukemic cells of these patients in the colony cells. Study of eight cases of acute non-lymphocytic leukemia, four cases of blast crisis of CML, and seven cases of CML chronic phase revealed the assay to be efficient in growing large numbers of leukemic blast colonies, as compared to the Robinson culture assay where large colony formation is only found in chronic leukemia [10]. Removal of the progenitors of lymphocytic colonies was sometimes incomplete in acute leukemia but not in CML.