In-vitro cloning techniques for hemopoietic cells: clinical applications.

Proliferating populations of neutrophils, monocytes, eosinophils, erythroid cells, and T-lymphocytes from normal subjects or patients with various diseases can now be analysed by colony formation in semisolid cultures. These cultures accurately determine the number and proliferative activity of the precursor cells of each population and can also be used to monitor the levels of specific regulatory factors (for example, erythropoietin, colony-stimulating factor) in the serum or urine of such patients. Studies using semisolid cultures have shown that the leukemic cells in chronic and acute myeloid leukemia remain dependent on the normal regulator, granulocyte-macrophage colony-stimulating factor, for proliferation. The cultures have proved valuable in the prognostic assessment of acute leukemic patients and in monitoring impending changes in the clinical status of patients with acute or chronic myeloid leukemia or myeloproliferative disorders.