The two most common sources of adult stem cells for clinical application in orthopaedics are bone marrow and adipose tissue. Both  bone marrow aspirate and linoaspirate contain  different cell fractions. When bone marrow aspirate is centrifuged, bone marrow aspirate concentrate can be obtained from buffy-coat layer which contains mononuclear cells including very low percentage of mesenchymal stem cells. When lipoaspirate is treated by enzymes and undergoes differential centrifugation, fat and mature adipocytes in the upper layer are separated. The bottom layer is stromal vascular fraction that contains low percentage of mesenchymal stem cells. When bone marrow aspirate concentrate and stromal vascular fraction are put into a monolayer culture on plastic dishes and passaged, cells that have characteristics of mesenchymal stem cells can be isolated.