title: Structural and mechanical properties of the proliferative zone of the developing murine growth plate cartilage assessed by atomic force microscopy.
abstract: The growth plate (GP) is a dynamic tissue driving bone elongation through chondrocyte proliferation, hypertrophy and matrix production. The extracellular matrix (ECM) is the major determinant of GP biomechanical properties and assumed to play a pivotal role for chondrocyte geometry and arrangement, thereby guiding proper growth plate morphogenesis and bone elongation. To elucidate the relationship between morphology and biomechanics during cartilage morphogenesis, we have investigated age-dependent structural and elastic properties of the proliferative zone of the murine GP by atomic force microscopy (AFM) from the embryonic stage to adulthood. We observed a progressive cell flattening and arrangement into columns from embryonic day 13.5 until postnatal week 2, correlating with an increasing collagen density and ECM stiffness, followed by a nearly constant cell shape, collagen density and ECM stiffness from week 2 to 4 months. At all ages, we found marked differences in the density and organization of the collagen network between the intracolumnar matrix, and the intercolumnar matrix, associated with a roughly two-fold higher stiffness of the intracolumnar matrix compared to the intercolumnar matrix. This difference in local ECM stiffness may force the cells to arrange in a columnar structure upon cell division and drive bone elongation during embryonic and juvenile development.
authors.affiliation: Center for Applied Tissue Engineering and Regenerative Medicine (CANTER), Munich University of Applied Sciences, Munich, Germany; Laboratory of Experimental Surgery and Regenerative Medicine (ExperiMed), Department of Surgery, Clinical Center University of Munich, Munich, Germany; Center for NanoScience (CeNS), University of Munich, Munich, Germany.
authors.forename: Carina
authors.initials: C
authors.lastname: Prein
authors.affiliation: Center for Applied Tissue Engineering and Regenerative Medicine (CANTER), Munich University of Applied Sciences, Munich, Germany.
authors.forename: Niklas
authors.initials: N
authors.lastname: Warmbold
authors.affiliation: Laboratory of Experimental Surgery and Regenerative Medicine (ExperiMed), Department of Surgery, Clinical Center University of Munich, Munich, Germany.
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Farkas
authors.affiliation: Center for Applied Tissue Engineering and Regenerative Medicine (CANTER), Munich University of Applied Sciences, Munich, Germany; Laboratory of Experimental Surgery and Regenerative Medicine (ExperiMed), Department of Surgery, Clinical Center University of Munich, Munich, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Schieker
authors.affiliation: Center for Applied Tissue Engineering and Regenerative Medicine (CANTER), Munich University of Applied Sciences, Munich, Germany; Laboratory of Experimental Surgery and Regenerative Medicine (ExperiMed), Department of Surgery, Clinical Center University of Munich, Munich, Germany.
authors.forename: Attila
authors.initials: A
authors.lastname: Aszodi
authors.affiliation: Center for Applied Tissue Engineering and Regenerative Medicine (CANTER), Munich University of Applied Sciences, Munich, Germany; Center for NanoScience (CeNS), University of Munich, Munich, Germany. Electronic address: hauke.clausen-schaumann@hm.edu.
authors.forename: Hauke
authors.initials: H
authors.lastname: Clausen-Schaumann
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D002358:Cartilage, Articular / Q000254:growth & development* / Q000502:physiology; D049109:Cell Proliferation; D005109:Extracellular Matrix / Q000502:physiology; D006132:Growth Plate / Q000254:growth & development / Q000502:physiology* / Q000648:ultrastructure*; D051379:Mice; D018625:Microscopy, Atomic Force; D013314:Stress, Mechanical
keywords: AFM; Atomic force microscopy; Biomechanics; Elasticity; Growth plate; Proliferative zone