title: Regulation of the differentiation of mesenchymal stem cells in vitro and osteogenesis in vivo by microenvironmental modification of titanium alloy surfaces.
abstract: To mimic the extracellular microenvironment of bone, a bioactive multilayered structure of gelatin/chitosan pair, containing bone morphogenetic protein 2(BMP2) and fibronectin (FN), was constructed onto Ti6Al4V surface via a layer-by-layer assembly technique. The successful fabrication of multilayered structure was confirmed by contact angle measurement, field emission scanning electron microscopy (FE-SEM) and confocal laser scanning microscopy (CLSM), respectively. Bioactive BMP2 released in a sustained manner along with the degradation of multilayered structure. MSCs grown onto the multilayer coated TC4 substrates displayed significantly higher (p < 0.01 or p < 0.05) production levels of alkaline phosphatase (ALP), mineralization and genes expressions of runt related transcription factor 2 (Runx2), osterix, osteocalcin (OC), osteopontin (OPN), ALP and collagen type Ⅰ(ColⅠ) compared to the controls after culture for 7 days and 21 days, respectively. More importantly, MicroCT analysis and histological observations demonstrated that the multilayer coated Ti6Al4V implants in vivo promoted the bone density and new bone formation around them after implantation for 4 weeks and 12 weeks, respectively. The results indicated that Ti6Al4V coated with biofunctional multilayers was beneficial for osteogenesis and integration of implant/bone. The study therefore presents an alternative to fabricate bio-functionalized Ti6Al4V-based implants for potential application in orthopedics field.
authors.affiliation: Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Hu
authors.forename: Kaiyong
authors.initials: K
authors.lastname: Cai
authors.forename: Zhong
authors.initials: Z
authors.lastname: Luo
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Liqi
authors.initials: L
authors.lastname: Li
authors.forename: Min
authors.initials: M
authors.lastname: Lai
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Hou
authors.forename: Yuran
authors.initials: Y
authors.lastname: Huang
authors.forename: Jinghua
authors.initials: J
authors.lastname: Li
authors.forename: Xingwei
authors.initials: X
authors.lastname: Ding
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
authors.forename: K L Paul
authors.initials: KL
authors.lastname: Sung
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000497:Alloys; D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000494:pharmacology; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000528:radiation effects; D002448:Cell Adhesion / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects*; D048430:Cell Shape / Q000187:drug effects; D060833:Cellular Microenvironment / Q000187:drug effects*; D020099:Coated Materials, Biocompatible / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D020007:Implants, Experimental; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects* / Q000201:enzymology; D051379:Mice; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D008856:Microscopy, Fluorescence; D010010:Osteoclasts / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D010012:Osteogenesis / Q000187:drug effects*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D013499:Surface Properties / Q000187:drug effects; D014025:Titanium / Q000494:pharmacology*; D014867:Water / Q000737:chemistry; D055114:X-Ray Microtomography
chemical_list: D000497:Alloys; D055396:Bone Morphogenetic Protein 2; D020099:Coated Materials, Biocompatible; D012333:RNA, Messenger; D014867:Water; C031462:titanium alloy (TiAl6V4); D014025:Titanium; D000469:Alkaline Phosphatase