Counting Cells in Human Bone Marrow

A method for estimation of human bone marrow cellularity is described. After bone marrow puncture, the aspirate is sieved, and the retained particles flushed with cold plasma. They are then aspirated in a glass capillary tube of known volume, and after centrifugation the packed material is measured. It is suspended in citric acid alcohol, and the number of nucleated cells is counted in a counting chamber. By simple arithmetic, the cellularity of bone marrow per cu. mm. can then be determined. The results of 90 counts are given. Values below 0.4 × 106 nucleated cells per cu. mm. bone marrow suggest bone marrow hypoplasia.