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The isolated heparin samples were also analyzed by 1H NMR spectroscopy to check the possible impurities, and the results show the presence of chondroitin sulfate and dermatan sulfate, as is the case for the heparin eluted from the commercial resin. Furthermore, the effects of some experimental variables including the adsorbent dosage, pH, time, and recycling on heparin adsorption were studied, and the results show that these resins can be used for efficient recovery of heparin.The main impetus of vascular tissue engineering is clinical translation, but an equally appealing and impactful use of engineered vascular tissues is as preclinical testing platforms for studying vascular disease and developing therapeutic drugs and understanding of physiologically relevant vascular biology. Developing model engineered tissues will aid in narrowing the significant knowledge gaps in functional tissue formation, which is regulated by intricate cell signaling in a three-dimensional space. In this study, we fabricated tubular engineered vascular tissues using cross-linked fibrinogen as a scaffold and nondifferentiated embryonic rat vascular smooth muscle cell line (A10 cells) and mouse embryonic multipotent mesenchymal progenitor cell line (10T1/2 cells) as model vascular cells. Fibrin gel dimensional contraction kinetics study showed that A10 cells embedded in the gel were unable to significantly contract the tissue compared to fibrin-only gels because of their undifferentiated state. In contrast, 10T1/2 cells differentiated with TGF-β1 to a vascular lineage were able to contract the tubular gel significantly owing to the contractile cytoskeletal stress fibers. Because of its vital role in vascular morphogenesis, tissue specification, and maturation, Notch signaling studies in engineered vascular tissues from A10 cells demonstrated cis-inhibition, whereas 10T1/2 cells activated Notch and its downstream targets Hes-1 and the smooth muscle α-actin genes. Taken together, this study showed that (i) contrary to the previously accepted notion, cell-type is important to gel contractions, and (ii) in engineered vascular tissues, Notch signaling is highly context-dependent, where cis-inhibition muted signal activation in A10 vascular cells, whereas Notch was fully activated in 10T1/2 cells. These findings may provide insights to fabricate functional vascular tissues.To achieve organization and function, engineered tissues require a scaffold that supports cell adhesion, alignment, growth, and differentiation. For skeletal muscle tissue engineering, decellularization has been an approach for fabricating 3D scaffolds that retain biological architecture. While many decellularization approaches are focused on utilizing animal muscle as the starting material, decellularized plants are a potential source of highly structured cellulose-rich scaffolds. Here, we assessed the potential for a variety of decellularized plant scaffolds to promote mouse and human muscle cell alignment and differentiation. After decellularizing a range of fruits and vegetables, we identified the green-onion scaffold to have appropriate surface topography for generating highly confluent and aligned C2C12 and human skeletal muscle cells (HSMCs). The topography of the green-onion cellulose scaffold contained a repeating pattern of grooves that are approximately 20 μm wide by 10 μm deep. The outer white section of the green onion had a microstructure that guided C2C12 cell differentiation into aligned myotubes. Quantitative analysis of C2C12 and HSMC alignment revealed an almost complete anisotropic organization compared to 2D isotropic controls. Our results demonstrate that the decellularized green onion cellulose scaffolds, particularly from the outer white bulb segment, provide a simple and low-cost substrate to engineer aligned human skeletal muscle.Purpose Gene therapy is an important therapeutic strategy for cancer. Nanoparticles are used for noninvasive gene delivery, which has great potential in tumor therapy. However, it is a challenge to construct a targeted gene delivery vector with high gene delivery efficiency, good biocompatibility, and multiple functions. Method Herein, we designed magnetic mesoporous silica nanoparticle loading microbubbles (M-MSN@MBs) for ultrasound-mediated imaging and gene transfection. The plasmid DNA (pDNA) was encapsulated into the pores of M-MSNs. Also, the pDNA-carrying M-MSNs were loaded in the lipid microbubbles. Results The gene vector presented good biocompatibility, DNA binding stability, ultrasound imaging performance, and magnetic responsiveness. The polyethyleneimine (PEI)-modified M-MSNs effectively protected the loaded pDNA from enzyme degradation. The cytotoxicity of M-MSNs was significantly reduced via encapsulating in lipid microbubbles. Upon the magnetic field, M-MSN@MBs were attracted to the tumor area. Then, ultrasound-targeted microbubble destruction (UTMD) not only released loaded M-MSNs but also facilitated M-MSNs delivery to tumor tissue by opening blood-tumor barrier and increasing the cytomembrane permeability, and ultimately improved the pDNA delivery efficiency. Conclusion Our findings suggested that the developed ultrasound-responsive gene delivery system was a promising platform for gene therapy, which could noninvasively enhance tumor gene transfection.Enzymatic cross-linking of polymer-catechol conjugates in the presence of horseradish peroxidase (HRP) and H2O2 has emerged as an important method to fabricate in situ-forming, injectable hydrogels. Subsequently, tissue adhesion studies using catechol-containing polymers were extensively reported. However, because of the presence of numerous variables such as polymer concentration, oxidizing agent/enzyme, and stoichiometry, the design of the polymer with optimized tissue adhesive property is still challenging. https://www.selleckchem.com/ In this study, a poly(γ-glutamic acid) (γ-PGA)-dopamine (PGADA) conjugate was synthesized, and in situ hydrogels were fabricated via enzymatic cross-linking of a catechol moiety. To optimize the tissue adhesive property of the PGADA hydrogel, the effect of various factors, such as polymer concentration, catechol substitution degree (DS), HRP concentration, and H2O2 content, on the gelation behavior and mechanical strength was investigated. The gelation behavior of PGADA hydrogels was characterized using a rheometer and rotational viscometer. Also, the possibility of its use as a tissue adhesive was examined by evaluating the tissue adhesion strength in vitro and ex vivo.The successful tissue integration of a biomedical material is mainly determined by the inflammatory response after implantation. Macrophage behavior toward implanted materials is pivotal to determine the extent of the inflammatory response. Hydrogels with different properties have been developed for various biomedical applications such as wound dressings or cell-loaded scaffolds. However, there is limited investigation available on the effects of hydrogel mechanical properties on macrophage behavior and the further host inflammatory response. To this end, methacrylate-gelatin (GelMA) hydrogels were selected as a model material to study the effect of hydrogel stiffness (2, 10, and 29 kPa) on macrophage phenotype in vitro and the further host inflammatory response in vivo. Our data showed that macrophages seeded on stiffer surfaces tended to induce macrophages toward a proinflammatory (M1) phenotype with increased macrophage spreading, more defined F-actin and focal adhesion staining, and more proinflammatory cytokine secretion and cluster of differentiation (CD) marker expression compared to those on surfaces with a lower stiffness. When these hydrogels were further subcutaneously implanted in mice to assess their inflammatory response, GelMA hydrogels with a lower stiffness showed more macrophage infiltration but thinner fibrotic capsule formation. The more severe inflammatory response can be attributed to the higher percentage of M1 macrophages induced by GelMA hydrogels with a higher stiffness. Collectively, our data demonstrated that macrophage behavior and the further inflammatory response are mechanically regulated by hydrogel stiffness. The macrophage phenotype rather than the macrophage number predominately determined the inflammatory response after the implantation, which can provide new insights into the future design and application of novel hydrogel-based biomaterials.The promise of antiangiogenic therapy for the treatment of breast cancer has been limited by the inability to selectively disrupt the established tumor vasculature. Here, we report the development of rationally designed antibody drug conjugates (ADCs) that can selectively recognize and attack breast tumor-associated endothelial cells (BTECs), while sparing normal endothelial cells (NECs). We first performed a quantitative and unbiased screening of a panel of cancer-related antigens on human BTECs and identified CD105 as the optimal ADC target on these cells. We then used clinically approved ADC linkers and cytotoxic drugs to engineer two CD105-targeted ADCs CD105-DM1 and CD105-MMAE and evaluated their in vitro efficacy in human BTECs and NECs. We found that both CD105-DM1 and CD105-MMAE exhibited highly potent and selective cytotoxicity against BTECs with IC50 values of 3.2 and 3.7 nM, respectively, significantly lower than their IC50 values on NECs (8-13 fold). Our proof-of-principle study suggests that CD105-targeted ADCs are promising antiangiogenic agents that have the potential to be used to inhibit the established tumor vasculature of breast tumors in a safe and precise manner.The foreign body response (FBR) has impaired progress of new implantable medical devices through its hallmark of chronic inflammation and foreign body giant cell (FBGC) formation leading to fibrous encapsulation. Macrophages are known to drive the FBR, but efforts to control macrophage polarization remain challenging. The goal for this study was to investigate whether prostaglandin E2 (PGE2), and specifically its receptors EP2 and/or EP4, attenuate classically activated (i.e., inflammatory) macrophages and macrophage fusion into FBGCs in vitro. Lipopolysaccharide (LPS)-stimulated macrophages exhibited a dose-dependent decrease in gene expression and protein production of tumor necrosis factor alpha (TNF-α) when treated with PGE2. This attenuation was primarily by the EP4 receptor, as the addition of the EP2 antagonist PF 04418948 to PGE2-treated LPS-stimulated cells did not recover TNF-α production while the EP4 antagonist ONO AE3 208 did. However, direct stimulation of EP2 with the agonist butaprost to LPS-stimulated macrophages resulted in a ∼60% decrease in TNF-α secretion after 4 h and corresponded with an increase in gene expression for Cebpb and Il10, suggesting a polarization shift toward alternative activation through EP2 alone. Further, fusion of macrophages into FBGCs induced by interleukin-4 (IL-4) and granulocyte-macrophage colony-stimulating factor (GM-CSF) was inhibited by PGE2 via EP2 signaling and by an EP2 agonist, but not an EP4 agonist. The attenuation by PGE2 was confirmed to be primarily by the EP2 receptor. Mrc1, Dcstamp, and Retlna expressions increased upon IL-4/GM-CSF stimulation, but only Retnla expression with the EP2 agonist returned to levels that were not different from controls. This study identified that PGE2 attenuates classically activated macrophages and macrophage fusion through distinct EP receptors, while targeting EP2 is able to attenuate both. In summary, this study identified EP2 as a potential therapeutic target for reducing the FBR to biomaterials.
Here's my website: https://www.selleckchem.com/
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