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The presence of three dimensional support is indispensable condition for successful regeneration of the tissue. In the absence of natural scaffold, or absence of its artificial substitute, regeneration is not possible. The advantage of natural building blocks to create new scaffolds results from the requirements of the materials structures used for tissue regeneration: biocompatibility, biodegradability, lack of cytotoxicity and desirable mechanical properties. Application of these building blocks for the preparation of three dimensional materials should ensure completely biocompatibility of the temporary extracellular matrix equivalent, thus offering construct resembling a natural milieu for the cells and finally regeneration of tissues. These include framework with elements stimulating adhesion of in vitro grown cells, growth factors, hormones and vitamins offered as a completed ingredients in the commercially available culture media. 3D frameworks applied for cell growing should facilitate formation of required tissue shape and size as well as appropriate functioning of the cells. The key factor for the successful regeneration of tissues is the function of the scaffold determining the environment for growing cells, directing proliferation and regulating differentiation processes. The basic feature of the cellular scaffold, determining its functioning is porosity. Pore diameter and their abundance consists a critical factor for penetration of cells into the interior of the implant and finally for successful regeneration of damaged tissue. The progress of tissue regeneration in vitro depends on the presence of cytokines and growth factors, which are controlling cell differentiation process. Nowadays neither of implant material offered on the market has a property comparable to the natural tissue. However, there are many reports presenting preliminary experiments conducted towards attaining novel supports for regenerative medicine derived from peptides and formed by their self-organization. The most advanced of them are known under trade name PuraMatrix, which recently were applied for the regeneration of soft tissues. However, due to tendency of this materials for hydrogels formation, characteristic for them are disadvantageous mechanical properties. The alternative approach based on application of native ECM proteins was also taken into consideration. The weak points of this materials are the susceptibility of proteins towards proteolytic enzymes and theirs immunogenic properties. The diversity of peptide modules give the opportunity to design and synthesize a variety of biomaterials that mimic the structural complexity of the natural ECM.
Lactoferrin, a glycoprotein found in milk, has stimulated osteoblast proliferation and differentiation, but has remained relatively unexplored as a biomaterial component. In this study, artificial extracellular matrices consisting of fibrils of collagen type I containing lactoferrin were used as coatings for the biocompatible polymer poly(lactic-co-glycolic acid) (PLGA). The numbers of cells, their viability and proliferation rate were evaluated in various time intervals. Additionally, cell initial spreading area on day 1 was measured. The results show that lactoferrin accelerates fibril-logenesis, leads to increased osteoblast cell numbers 1 and 3 days post-seeding, and encourages their proliferation in each of the tested time intervals.
In this paper we investigate a mathematical model of cancer invasion of tissue, which incorporates haptotaxis, chemotaxis, proliferation and degradation rates for cancer cells and the extracellular matrix, kinetics of urokinase receptor, and urokinase plasminogen activator cycle. We solve the model using spectrally accurate approximations and compare its numerical solutions with laboratory data. The spectral accuracy allows to use low-dimensional matrices and vectors, which speeds up the computations of the numerical solutions and thus to estimate the parameter values for the model equations. Our numerical results demonstrate correlations between numerical data computed from the mathematical model and in vivo tumour growth rates from prostate cell lines.
Content available remote Cell attachment on ion implanted titanium surface
Purpose: Of outmost importance for the successful use of an implant is a good adhesion of the surrounding tissue to the biomaterial. In addition to the surface composition of the implant, the surface topography also influences the properties of the adherent cells. In the present investigation, ion implanted and untreated surfaces were compared for cell adhesion and spreading. Design/methodology/approach: The surface topography of the surfaces were analyzed using AFM and the cell studies with SEM. Findings: The results of our present investigation is indicative of the fact that ion implanted titanium surface offer better cell binding affinity compared to untreated/polished surface. Practical implications: Success of non-biodegradable implants will first and foremost depend on biocompatibility, followed by the capacity of the surface topography of the implants to evince desired cell matrix, surface cell matrix interactions. In the present study, the cell growth on ion implanted Ti material is analyzed and discussed. Originality/value: In this paper, we have utilized ion implantation technique, which will produce nano-texturing of the surface without producing any detrimental effects to both the dimensions and properties of the implants.
Celem pracy była ocena stabilności struktury macierzy zewnątrzkomórkowej osierdzia świni po usunięciu z nich komórek. Badano wpływ substancji powodujących usuwanie komórek na właściwości biochemiczne i morfologiczne tkanek. Tkanki traktowano roztworami zawierającymi trypsynę i wersenian sodu (EDTA) lub dodecylosiarczan sodu (SDS) i chlorek sodu (NaCl). W badaniach wykorzystano elektroforezę SDS-PAGE i mikroskopię optyczną. Wykazano, że oddziaływanie na tkanki roztworu zawierającego 0,05% trypsyny i 0,02% EDTA pozwala na uzyskanie materiału bezkomórkowego.
The aim of the present study was to evaluate the stability of the extracellular matrix structure in porcine pericardium after their decellularization. The influence of decellularizing substances on the tissues biochemical and morphological properties has been investigated. Tissues have been treated with solutions containing trypsin and sodium versenate (EDTA) or sodium dodecyl-sulfate (SDS) and sodium chloride. The SDS-PAGE electrophoresis and the optical microscopy have been used in researches. It has been shown that the tissues treatment with the solution containing 0.05% trypsin and 0.02% EDTA allows to obtain the acellular material.
Arterial bypass surgery with synthetic vascular prostheses achieves poor patency rates compared to autogenous natural materials, and this is a challenge for tissue engineering research concerning small caliber vascular grafts. Modifications of the prosthetic surface followed by endothelial cell seeding may reduce thrombogenicity and intimal hyperplasia. Planar polyethylene terephthalate (PET) vascular prosthetic samples were impregnated with the copolymer poly(glycolide-L-lactide) (PGL) or with the terpolymer poly(glycolide-L-lactide-(e)caprolactone) (PGLCap) in order to lower the permeability of the knitted fabrics and ensure a less adhesive background. Subsequent modification with adhesive protein assemblies composed of collagen type I (Co) in conjunction with laminin (LM), fibronectin (FN) or fibrin (Fb) gel was performed to enhance cell adhesion. Bovine pulmonary artery endothelial cells (EC) of the CPAE line were seeded on to the coatings and subjected to static tissue culture conditions for 7 days. Impregnation of the PET prostheses decreased the initial adhesion and proliferation of the EC. After coating with the protein assemblies, the impregnated PET provided better substrates for cell culture than the protein-coated PET, on which the EC population started decreasing after 4 days of culture. The cells proliferated better on the CoFN, CoFb and CoFbFN coatings than on the Co and CoLM coatings. Impregnation type and adhesive matrix protein deposition may play an important role in successful endothelialization, healing and clinical performance of vascular grafts.
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