TIME-LAPSE VIDEO RECORDINGS OF HIGHLY PURIFIED HUMAN HEMATOPOIETIC PROGENITOR CELLS IN CULTURE

Major hurdles in studies of stem cell biology include the low frequenc y and heterogeneity of human hematopoietic precursor cells in bone mar row and the difficulty of directly studying the effect of various cult ure conditions and growth factors on such cells. We have adapted the c ell analyzer imaging system for monitoring and recording the morpholog y of limited numbers of cells under various culture conditions. Hemato poietic progenitor cells with a CD34+ CD45RA(lo) CD71lo phenotype were purified from previously frozen organ donor bone marrow by fluorescen ce activated cell sorting. Cultures of such cells were analyzed with t he imaging system composed of an inverted microscope contained in an i ncubator, a video camera, an optical memory disk recorder and a comput er-controlled motorized microscope XYZ precision stage. Fully computer -controlled video images at defined XYZ positions were captured at sel ected time intervals and recorded at a predetermined sequence on an op tical memory disk. In this study, the cell analyzer system was used to obtain descriptions and measurements of hematopoietic cell behavior, like cell motility, cell interactions, cell shape, cell division, cell cycle time and cell size changes under different culture conditions.