Clinical applications of bone-marrow culture.

The use of in-vitro culture methods for studying human haemopoietic cells has advanced greatly since 1970. These methods have contributed to our understanding of the mechanisms controlling granulopoiesis though the physiological role of colony-stimulating factor needs further clarification. In leukaemia they offer an approach to the study of possible causal factors and to the characterisation of leukaemic-cell defects. Results already obtained support the concept that the bone-marrow in acute myeloid leukaemia consists of coexisting populations of normal and leukaemic cells, with a leukaemic clone predominating in relapse and normal clones regenerating in remission. For the individual patient, in-vitro methods may prove useful in assessing prognosis and in confirming the completeness of remission; the detection of early relapse may then indicate the need for changing or re-instituting therapy. Further studies may aid the classification of the "preleukaemic" states and may help in the identification of the various causes of neutropenia.