title: Abnormal arrangement of a collagen/apatite extracellular matrix orthogonal to osteoblast alignment is constructed by a nanoscale periodic surface structure.
abstract: Morphological and directional alteration of cells is essential for structurally appropriate construction of tissues and organs. In particular, osteoblast alignment is crucial for the realization of anisotropic bone tissue microstructure. In this article, the orientation of a collagen/apatite extracellular matrix (ECM) was established by controlling osteoblast alignment using a surface geometry with nanometer-sized periodicity induced by laser ablation. Laser irradiation induced self-organized periodic structures (laser-induced periodic surface structures; LIPSS) with a spatial period equal to the wavelength of the incident laser on the surface of biomedical alloys of Ti-6Al-4V and Co-Cr-Mo. Osteoblast orientation was successfully induced parallel to the grating structure. Notably, both the fibrous orientation of the secreted collagen matrix and the c-axis of the produced apatite crystals were orientated orthogonal to the cell direction. To the best of our knowledge, this is the first report demonstrating that bone tissue anisotropy is controllable, including the characteristic organization of a collagen/apatite composite orthogonal to the osteoblast orientation, by controlling the cell alignment using periodic surface geometry.
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
authors.forename: Aira
authors.initials: A
authors.lastname: Matsugaki
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
authors.forename: Gento
authors.initials: G
authors.lastname: Aramoto
authors.affiliation: Canon Machinery Inc., 85, Minami Yamada-cho, Kusatsu, Shiga 525-8511, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Ninomiya
authors.affiliation: Canon Machinery Inc., 85, Minami Yamada-cho, Kusatsu, Shiga 525-8511, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sawada
authors.affiliation: Department of Electrical and Materials Science, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hata
authors.affiliation: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan. Electronic address: nakano@mat.eng.osaka-u.ac.jp.
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Nakano
mesh_terms: D000497:Alloys; D000818:Animals; D016880:Anisotropy; D001031:Apatites / Q000737:chemistry*; D001857:Bone Matrix / Q000187:drug effects / Q000378:metabolism; D002113:Calcification, Physiologic / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D002478:Cells, Cultured; D003094:Collagen / Q000737:chemistry*; D005109:Extracellular Matrix / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D007150:Immunohistochemistry; D008810:Mice, Inbred C57BL; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry*; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects; D013059:Spectrum Analysis, Raman; D013499:Surface Properties; D014025:Titanium / Q000494:pharmacology
chemical_list: D000497:Alloys; D001031:Apatites; C031462:titanium alloy (TiAl6V4); D003094:Collagen; D014025:Titanium
keywords: Apatite orientation; Collagen structure; Laser-induced periodic surface structures (LIPSS); Microbeam X-ray diffraction; Osteoblast