Characterization of proliferative and quiescent leukemic cells by flow cytometry.

Leukemic cells obtained from the peripheral blood and bone marrow of two patients were separated into kinetically active and kinetically quiescent subpopulations by centrifugal elutriation. The subpopulations of cells were compared to each other and to the parent populations by means of flow cytometry and autoradiography. The larger kinetically active subpopulation differed from the original unseparated cells and from the small cell population in containing a larger amount of RNA and having a greater proportion of cell in late G1. Subpopulations of large and equivalently sized cells obtained from the bone marrow and peripheral blood were compared and despite essentially identical size distributions the marrow cells were more kinetically active.