Bovine decellularized amniotic membrane: Extracellular matrix as scaffold for mammalian skin

Decellularized membranes (DM) were obtained from bovine amniotic membranes (BAM) using four different decellularization protocols, based on physical, chemical, and mechanical treatment. The new material was used as a biological scaffold for in vitro skin cell culture. The DM were characterized using hematoxylin-eosin assay, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR-ATR), and differential scanning calorimetry (DSC). The in vitro cytotoxicity of DM was evaluated using MTT. The efficacy of decellularization process was assessed throughDNAquantification and electrophoresis. All the used protocols showed a high effectiveness in terms of elimination of native cells, confirmed by DNA extraction and quantification, electrophoresis, and SEM, although protocol IV removes the cellular contents and preserve the native extracellular matrix (ECM) architecture which it can be considered as the most effective in terms of decellularization. FTIR-ATR and DSC on the other hand, revealed the effects of decellularization on the biochemical composition of the matrices. There was no cytotoxicity and the biological matrices obtained were a source of collagen for recellularization. The matrices of protocols I, II, and III were degraded at day 21 of cell culture, forming a gel. The biocompatibility in vitro was demonstrated; hence these matrices may be deemed as potential scaffold for epithelial tissue regeneration

Novel biopolimeric system for bone tissue engineering: Crosslinked and plasticized chitosan/poly vinyl alcohol/hydroxiapatite scaffolds

Porous scaffolds made of chitosan, polyvinyl alcohol and hydroxyapatite were prepared via freeze-drying method. In this matter, three different volume ratios of polymer solutions (1:1, 1:3, 3:1) and constant hydroxyapatite mass ratio were blended. Glutaraldehyde and glycerol were added as a polymer-chain crosslinker and plasticizer, respectively. The obtained scaffolds were used to test bone proliferation and potential for bone regeneration and they were characterized through FTIR, mechanical tests, cell cultures and swelling tests. Every quantitative measurement was statistically tested using two-way analysis of variance (ANOVA) with < 0.05. Partial results from cell culture have been obtained, showing faster cell differentiation in the scaffolds combined with glutaraldehyde and glycerol. Crosslinked scaffolds showed better swelling conditions than those that were not subject to this chemical reaction. Besides, samples with higher chitosan ratio exhibited better swelling behavior. Experiments suggest that the bio-polymeric system has potential for bone tissue regeneration. © 2018 IEEE.Universidad Manuela Beltran (Bogota, Colombia); Ministry of Education, Youth and Sports of the Czech Republic - Program NPU I [LO1504