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Decellularized tissue hydrogels, especially that mimic the native tissue, have a high potential for tissue engineering, three-dimensional (3D) cell culture, bioprinting, and therapeutic agent encapsulation due to their excellent biocompatibility and ability to facilitate the growth of cells. It is important to note that the decellularization process significantly affects the structural integrity and properties of the extracellular matrix, which in turn shapes the characteristics of the resulting hydrogels at the macromolecular level. Therefore, our study aims to identify an effective chemical decellularization method for sheep lung tissue, using a mixing/agitation technique with a range of detergents, including commonly [Sodium dodecyl sulfate (SDS), Triton X-100, and 3-((3-cholamidopropyl) dimethylammonio)-1-propanesulfonate] (CHAPS), and rarely used (sodium cholate hydrate, NP-40, and 3-[N,N-Dimethyl(3-myristoylaminopropyl)ammonio]propanesulfonate) (ASB-14). After the effectiveness of the used detergents on decellularization was determined by histological and biochemical methods, lung derived decellularized extracellular matrix was converted into hydrogel. We investigated the interactions between lung cells and decellularized extracellular matrix using proliferation assay, scanning electron microscopy, and immunofluorescence microscopy methods on BEAS-2B cells in air-liquid interface. Notably, this study emphasizes the effectiveness of ASB-14 in the decellularization process, showcasing its crucial role in removing cellular components while preserving vital extracellular matrix biological macromolecules, including glycosaminoglycans, collagen, and elastin. The resulting hydrogels demonstrated favorable mechanical properties and are compatible with both cell-cell and cell-extracellular matrix interactions. [ABSTRACT FROM AUTHOR]

Injectable bone substitute (IBS) materials are commonly used to fill irregular-shaped bone voids in non-load-bearing areas and can offer greater utility over those which are in prefabricated powder, granule, or block forms. This work investigates the impact of liquid-to-solid ratio (LSR) on the rheology and cytocompatibility of IBSs formulated from bioactive glass particles and β-tricalcium phosphate (β-TCP) in glycerol and poly(ethylene glycol) (PEG). IBS formulations of varying LSR were prepared and packed in 3 cc open-bore syringes and sterilized via gamma irradiation (10 kGy, 25 kGy). Gamma-irradiated formulations with high PEG content required the highest (73 N) mechanical force for injection from syringes. Oscillatory viscosity measurements revealed that the viscosity of samples was directly proportional to glycerol content. PEG and glycerol displayed competing effects on the washout resistance and cohesiveness of samples, which were based on total weight loss in media and Ca2+ ion release, respectively. Cell viability in 24-h extracts of 10 kGy gamma-sterilized and 25 kGy gamma-irradiated samples were 22.94% and 56.53%, respectively. The research highlights the complex interplay of IBS components on IBS rheology and, moreover, the cytotoxicity behaviors of beta-tricalcium phosphate-based injectable bone substitutes by in vitro experiments. [ABSTRACT FROM AUTHOR]

Facial bone fractures in facial injuries resulting from severe trauma can be treated using plate and screw systems. Depending on the location of the fracture, the fracture lines are brought end to end and fixed with plates and screws. Metallic implants are at risk of endogenous infection and there are inherent problems associated with their use, such as stress shielding phenomena, pain, and local irritation. After the bone has healed, a second surgery is needed to remove the metallic fixation. Considering these problems, it is important to use biodegradable plates instead of metal plates. Biodegradable fracture fixation plates degrade slowly in the human body, causing less pain and stress, and there is no need for a second procedure to remove the synthetic material. As these plates decompose, the load will also decrease. There are no toxic and mutagenic effects in an absorbable implant. However, there are some problems with the use of these implants, such as inflammatory response, rapid loss of initial implant strength, higher fracture rates, insufficient hardness of the implants, and weakness compared to metallic implants. In this study, biodegradable plates were designed for use in maxillofacial bone injuries, and treatment plates were prepared using extrusion and injection molding. Different proportions of trimethylene carbonate (TMC), poly-L-lactate (LPLA), poly(D,L-lactate) (DLPLA), polyglycolate (PGA) and beta-tricalcium phosphate (β-TCP) are mixed by extrusion to produce composites by injection molding. Plates were obtained. The degradation, morphological, thermal, and mechanical behaviors of the obtained products were examined. [ABSTRACT FROM AUTHOR]

To search for a suitable meniscus repair material, acellular hybrid scaffolds consisting of in situ cross-linkable 3-D interpenetrating network structures were obtained by decellularization of the meniscus tissues followed by integration of the gel system. Decellularization efficiency was confirmed using a DNA quantification assay (82% decrease in DNA content) and histological stainings. In the second part of the study, the gelatin molecule was functionalized by adding methacrylic anhydride and the degree of functionalization was found to be 75% by (Proton-Nuclear Magnetic Resonance) 1H-NMR. Using this, a series of hybrid constructs named GelMA-Hybrid (G-Hybrid), GELMA/PEGDMA-Hybrid (PG-Hybrid), and GelMA/PEGDMA/HAMA-Hybrid (PGH-Hybrid) were prepared by cross-linking with UVA. Changes in the chemical structure were determined with Fourier Transform Infrared Spectrophotometer (FTIR). Water uptake capacities of cross-linked hybrid structures were measured in swelling studies, and it was found that hybrid scaffolds showed similar swelling properties compared to native counterparts. By compressive mechanical tests, enhanced mechanical properties were revealed in cross-linked scaffolds with PGH-Hybrid having the highest cross-link density. Protein denaturation and decomposition transition temperatures were improved by adding hydrogels to acellular scaffolds according to thermal gravimetric analyses (TGA). Cross-linked acellular scaffolds have exhibited a behavior close to native tissues with below 25% mass loss in phosphate buffer saline (PBS) and enzymatic solution. Cell viability was examined through Alamar Blue on the first day and cell viability in hybrid constructs was found to be above 80% while it was closer to the control group on the 7th day. It was concluded that the developed biomaterials could be used in meniscus tissue engineering with their tunable physicochemical and mechanical properties. [ABSTRACT FROM AUTHOR]

In this paper, gelatin methacrylate hydrogel scaffold, functionalized with growth factors loaded alginate-chitosan core-shell nanoparticles, were developed to enhance chondrogenic differentiation of adipose-derived mesenchymal stem cells. With the chosen preparation conditions, the encapsulation efficiency of transforming growth factorβ-1 (TGFβ-1) and insulin-like growth factor-1 (IGF-1) was calculated at 93.34% and 91.92%, respectively. The assay groups which contain loaded nanoparticles in hydrogels exhibited the highest DNA and glycosaminoglycan contents with 2.93 and 573.60 µg/sample, respectively. Moreover, in the same group, it was observed that the amount of collagen also increased by 3.6-fold. Thus, the functionalized scaffold is promising construct for tissue engineering applications. [ABSTRACT FROM AUTHOR]

The microarchitecture of bone tissue engineering (BTE) scaffolds has been shown to have a direct effect on the osteogenesis of mesenchymal stem cells (MSCs) and bone tissue regeneration. Poly(glycerol sebacate) (PGS) is a promising polymer that can be tailored to have specific mechanical properties, as well as be used to create microenvironments that are relevant in the context of BTE applications. In this study, we utilized PGS elastomer for the fabrication of a biocompatible and bioactive scaffold for BTE, with tissue-specific cues and a suitable microstructure for the osteogenic lineage commitment of MSCs. In order to achieve this, the PGS was functionalized with a decellularized bone (deB) extracellular matrix (ECM) (14% and 28% by weight) to enhance its osteoinductive potential. Two different pore sizes were fabricated (small: 100–150 μm and large: 250–355 μm) to determine a preferred pore size for in vitro osteogenesis. The decellularized bone ECM functionalization of the PGS not only improved initial cell attachment and osteogenesis but also enhanced the mechanical strength of the scaffold by up to 165 kPa. Furthermore, the constructs were also successfully tailored with an enhanced degradation rate/pH change and wettability. The highest bone-inserted small-pore scaffold had a 12% endpoint weight loss, and the pH was measured at around 7.14. The in vitro osteogenic differentiation of the MSCs in the PGS-deB blends revealed a better lineage commitment of the small-pore-sized and 28% (w/w) bone-inserted scaffolds, as evidenced by calcium quantification, ALP expression, and alizarin red staining. This study demonstrates a suitable pore size and amount of decellularized bone ECM for osteoinduction via precisely tailored PGS elastomer BTE scaffolds. [ABSTRACT FROM AUTHOR]

Background: Decellularized tissues based on well‐conserved extracellular matrices (ECMs) are a common area of research in tissue engineering. Although several decellularization protocols have been suggested for several types of tissues, studies on the optic nerve have been limited. Methods: We report decellularization protocol with different detergent for the preparation of acellular optic nerve and tissues were examined. DNA, glycosaminoglycan (GAG), and collagen content of the groups were evaluated with biochemical analyses and examined with histological staining. Mechanical properties, chemical components as well as cytotoxic properties of tissues were compared. Results: According to the results, it was determined that TX‐100 (Triton X‐100) was insufficient in decellularization when used alone. In addition, it was noticed that 85% of GAG content was preserved by using TX‐100 and TX‐100‐SD (sodium deoxycholate), while this ratio was calculated as 30% for SDS. In contrast, the effect of the decellularization protocols on ECM structure of the tissues was evaluated by scanning and transmission electron microscopy (SEM and TEM) and determined their mechanical properties. Cytotoxicity analyses were exhibited minimum 95% cell viability for all groups, suggesting that there are no cytotoxic properties of the methods on L929 mouse fibroblast cells. Conclusions: The combination of TX‐100‐SD and TX‐100‐SDS (sodium dodecyl sulfate) were was determined as the most effective methods to the literature for optic nerve decellularization. [ABSTRACT FROM AUTHOR]

Millions of people require bone injury treatment and there have been many methods suggested for the stabilization of bone fractures. The need for the development of new methods is obvious since current stabilization methods are inadequate. Here, we described the development of polyurethane-based bone adhesives composites containing β-tricalcium phosphate ceramics in different sizes and ratios. To characterize the proposed materials, Fourier transform infrared spectroscopy, hydrogen-nuclear magnetic resonance, differential scanning calorimetry analyses together with scanning electron microscopy observations, and micro-computerized tomography imaging were examined. Furthermore, in vitro performance of the produced materials was tested by using MG63 human osteosarcoma cell line, and an ex vivo modeling study was conducted to test the mechanical performance of resulting materials using bovine rib bone. All materials were exhibited high porosity (above 90%) and homogeneous distribution of ceramic particles. Polyurethane scaffolds containing 40% (w/w) 1–2 mm β-tricalcium phosphate were shown the highest compressive strength as 1.34 ± 0.10 MPa. In addition, 85.75% cell viability was recorded according to the cytotoxicity analysis and also the cell proliferation was found highest in the same group. Taken into account the obtained results, the prepared polyurethane-based bone adhesive materials containing ceramics has a great potential to transform into a final product and meet a clinically significant medical need. [ABSTRACT FROM AUTHOR]

There has been a great interest in research towards elastomers and their composites with an attempt to obtain the desired biological and mechanical response to scaffold materials in bone tissue engineering. Composites made of ceramic‐thermoplastic mixtures have been shown success to deliver the inorganic component while fail to provide replacement of an elastic protein, that is, collagen, of the target bone tissue. Thus, in order to match up with the inherent elasticity of the native tissue, it is proposed an alternative to well‐known thermoplastic‐containing matrices by using a poly(glycerol‐sebacate) (PGS)–beta‐tricalcium phosphate elastomeric composite to offer flexibility and mechanical integrity. This study reports for the first time a successful extrusion of PGS containing biodegradable composites with shape‐memory feature. The resulting structures are physically and chemically characterized. In vitro cell culture performance of the obtained materials is investigated by using an MC3T3‐E1 mouse preosteoblast cell line. The materials obtained in this study can be shaped into the desired size and various forms via temperature stimuli. Resulting materials have been proposed for craniofacial tissue engineering as a bone filler in which surgeons need to shape biomaterials during the surgical procedure due to the complex geometry of the bones. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48689. [ABSTRACT FROM AUTHOR]