Characterization of subcultured myxoma cells from atrial myxoma. (a) After a period ranging from 1 to 3 weeks, phase-bright (arrow head) cells migrated over a layer of fibroblast-like cells (I, II). The phase-bright cells were collected, and Giemsa stain showed the cell with a large nucleus (III). Scale bar = 100 μm (I & II), =4 μm (III). (b) Quantification by FACS analysis of myxoma derived phase-bright cells. This cell population expresses robust CD44, CD19, and CD45.