Mechanical characterization of adult stem cells from bone marrow and perivascular niches

• Published in: Journal of biomechanics 2012-04, Vol.45 (7), p.1280-1287
• Main Authors: Ribeiro, Alexandre J.S, Tottey, Steven, Taylor, Richard W.E, Bise, Ryoma, Kanade, Takeo, Badylak, Stephen F, Dahl, Kris Noel
• Format: Article
• Language: English
• Subjects: Actin Cytoskeleton - physiology; Adult; Adult Stem Cells - physiology; Adults; Antigens, CD34 - metabolism; Behavior; Biological and medical sciences; Biomechanical Phenomena; Biotechnology; Blood Vessels - cytology; Bone marrow; Bone Marrow Cells - physiology; Cell Nucleus - physiology; Cells, Cultured; Cellular; Cytoskeleton; Deformation; Experiments; Fundamental and applied biological sciences. Psychology; Health. Pharmaceutical industry; Hematopoietic Stem Cells - physiology; Humans; Industrial applications and implications. Economical aspects; Injection; Mechanical properties; Mesenchymal Stromal Cells - physiology; Miscellaneous; Nucleoskeleton; Oxygen - metabolism; Physical Medicine and Rehabilitation; Porous materials; Regenerative medicine; Scaffolds; Stem Cell Niche - physiology; Stem cells; Stress, Mechanical; Therapy; Transplants & implants; Viscoelasticity
• ISSN: 0021-9290; 1873-2380
• DOI: 10.1016/j.jbiomech.2012.01.032

Abstract Therapies using adult stem cells often require mechanical manipulation such as injection or incorporation into scaffolds. However, force-induced rupture and mechanosensitivity of cells during manipulation is largely ignored. Here, we image cell mechanical structures and perform a biophysical characterization of three different types of human adult stem cells: bone marrow CD34+ hematopoietic, bone marrow mesenchymal and perivascular mesenchymal stem cells. We use micropipette aspiration to characterize cell mechanics and quantify deformation of subcellular structures under force and its contribution to global cell deformation. Our results suggest that CD34+ cells are mechanically suitable for injection systems since cells transition from solid- to fluid-like at constant aspiration pressure, probably due to a poorly developed actin cytoskeleton. Conversely, mesenchymal stem cells from the bone marrow and perivascular niches are more suitable for seeding into biomaterial scaffolds since they are mechanically robust and have developed cytoskeletal structures that may allow cellular stable attachment and motility through solid porous environments. Among these, perivascular stem cells cultured in 6% oxygen show a developed cytoskeleton but a more compliant nucleus, which can facilitate the penetration into pores of tissues or scaffolds. We confirm the relevance of our measurements using cell motility and migration assays and measure survival of injected cells. Since different types of adult stem cells can be used for similar applications, we suggest considering mechanical properties of stem cells to match optimal mechanical characteristics of therapies.