Isolation of bone marrow mesenchymal stem cells by natural sedimentation velocity method / 中国组织工程研究

ABSTRACT

BACKGROUND:In previous studies, it is satisfied to sorting bone marrow mesenchymal stem cels based on natural sedimentation combined with low permeation. Then, based on particle hydromechanics theory, the settling velocity of bone marrow mesenchymal stem cels in culture liquid is calculated. A simple and easy method of separation, purification and proliferation of bone marrow mesenchymal stem cels is established by natural sedimentation velocity. OBJECTIVE:To explore the feasibility of sorting bone marrow mesenchymal stem cels by natural sedimentation velocity method. METHODS:The density interval of rabbit bone marrow mesenchymal stemcels (ρ1) was determined by density gradient centrifugation method. The diameter of rabbit bone marrow mesenchymal stem cels (d) was measured by scanning electron microscope. The density of culture liquid (ρ2) was measured by liquid density meter. The viscosity of the culture liquid (μ) was measured by viscosity meter. The settling velocity of bone marrow mesenchymal stem cels (Vt) was derived from the above four numerical values with the appropriate formula. Bone marrow mesenchymal stem cels were sorted from bone marrow tissue by natural sedimentation velocity method. Cel proliferation, purity and differentiation were observed. Meanwhile, the primary culture time of three different cel sorting methods was recorded; the colony formation rate of rabbit bone marrow mesenchymal stem cels was determined. RESULTS AND CONCLUSION:(1) The diameter of rabbit bone marrow mesenchymal stem cels was (20.37±4.58) μm, and the setting velocity of rabbit bone marrow mesenchymal stem cels in the culture liquid was 50-55 mm/h. (2) Bone marrow mesenchymal stem cels could be successfuly isolated from bone marrow tissue of rabbits by the natural sedimentation velocity method, which could be induced into osteoblasts and adipocytes. (3) The natural sedimentation velocity group cost less time than the other two density gradient centrifugation groups in the primary culture stage. The colony formation rate of the natural sedimentation velocity group was higher than that of the other two groups. (4) Natural sedimentation velocity method did not impose any intervention measures for sorting cels, which maybe maximaly maintain cel viability and biological characteristics. The whole separation process was simple and safe, which may have little damage to the cels.