Please use this identifier to cite or link to this item:
|Title:||Engineering three-dimensional constructs of the periodontal ligament in hyaluronan-gelatin hydrogel films and a mechanically active environment|
In vitro model
|Citation:||Saminathan, A., Vinoth, K.J., Low, H.H., Cao, T., Meikle, M.C. (2013-12). Engineering three-dimensional constructs of the periodontal ligament in hyaluronan-gelatin hydrogel films and a mechanically active environment. Journal of Periodontal Research 48 (6) : 790-801. ScholarBank@NUS Repository. https://doi.org/10.1111/jre.12072|
|Abstract:||Background and Objective: Periodontal ligament (PDL) cells in stationary two-dimensional culture systems are in a double default state. Our aim therefore was to engineer and characterize three-dimensional constructs, by seeding PDL cells into hyaluronan-gelatin hydrogel films (80-100 μm) in a format capable of being mechanically deformed. Material and Methods: Human PDL constructs were cultured with and without connective tissue growth factor (CTGF) and fibroblast growth factor (FGF)-2 in (i) stationary cultures, and (ii) mechanically active cultures subjected to cyclic strains of 12% at 0.2 Hz each min, 6 h/d, in a Flexercell FX-4000 Strain Unit. The following parameters were measured: cell number and viability by laser scanning confocal microscopy; cell proliferation with the MTS assay; the expression of a panel of 18 genes using real-time RT-PCR; matrix metalloproteinases (MMPs) 1-3, TIMP-1, CTGF and FGF-2 protein levels in supernatants from mechanically activated cultures with Enzyme-linked immunosorbent assays. Constructs from stationary cultures were also examined by scanning electron microscopy and immunostained for actin and vinculin. Results: Although initially randomly distributed, the cells became organized into a bilayer by day 7; apoptotic cells remained constant at approximately 5% of the total. CTGF/FGF-2 stimulated cell proliferation in stationary cultures, but relative quantity values suggested modest effects on gene expression. Two transcription factors (RUNX2 and PPARG), two collagens (COL1A1, COL3A1), four MMPs (MMP-1-3, TIMP-1), TGFB1, RANKL, OPG and P4HB were detected by gel electrophoresis and Ct values < 35. In mechanically active cultures, with the exception of P4HB, TGFB1 and RANKL, each was upregulated at some point in the time scale, as was the synthesis of MMPs and TIMP-1. SOX9, MYOD, SP7, BMP2, BGLAP or COL2A1 were not detected in either stationary or mechanically active cultures. Conclusion: Three-dimensional tissue constructs provide additional complexity to monolayer culture systems, and suggest some of the assumptions regarding cell growth, differentiation and matrix turnover based on two-dimensional cultures may not apply to cells in three-dimensional matrices. Primarily developed as a transitional in vitro model for studying cell-cell and cell-matrix interactions in tooth support, the system is also suitable for investigating the pathogenesis of periodontal diseases, and importantly from the clinical point of view, in a mechanically active environment. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.|
|Source Title:||Journal of Periodontal Research|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Jul 18, 2018
WEB OF SCIENCETM
checked on Jul 9, 2018
checked on Jul 20, 2018
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.