Isolation of normal human megakaryocytes.

This paper reports a simple procedure for obtaining human megakaryocytes with a high purification and high recovery yield. Bone marrow cells, obtained from surgically removed ribs, were separated by a two-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, 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 two-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 I obtained.