Abstract
A simple procedure is reported for obtaining human megakaryocytes with a high purification and high recovery yield. Bone marrow cells, obtained from surgically removed ribs, were separated by a 2-step procedure. Initially, a single cell suspension was enriched in megakaryocytes by equilibrium density centrifugation, the low density cell fraction was subsequently layered over a shallow continuous albumin gradient in a glass sedimentation chamber. Megakaryocytes averaged 0.03 .+-. 0.02% of all nucleated cells in the starting marrow cell suspension, and after this procedure an average 80 .+-. 15% of the initial megakaryocyte population was recovered with a purity of 94 .+-. 4%. Previous methods, based upon the use of a 2-step procedure, are reviewed. The theory of velocity sedimentation is discussed with regard to the differences in the methodology used, which account for the different results obtained.