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Background To address the limitations of Cultivated Limbal Epithelial Transplantation (CLET) and the use of amniotic membrane (AM) in treating Limbal Stem Cell Deficiency (LSCD), we aimed to develop a Collagen/Silk Fibroin (Co/SF) scaffold enriched with Platelet-Rich Growth Factor (PRGF) to support the proliferation, maintenance, and differentiation of Wharton's jelly-derived mesenchymal stem cells (WJMSCs) into corneal epithelial cells (CECs). Method Scaffolds loaded with PRGF were evaluated through release studies, cytotoxicity assays, and cell differentiation. The proliferation and differentiation of WJMSCs and Limbal Epithelial Stem Cells (LESCs) were investigated using MTT assays, real-time PCR and immunostaining. Results The PRGF-loaded Co/SF scaffold significantly promoted the proliferation of both WJMSCs and LESCs in a concentration-dependent manner. Real-time PCR and immune staining revealed a significant increase in the expression of P63, ABCG2, and cytokeratin 3/12 markers in WJMSCs, a significant decrease in the expression of P63 and ABCG2, and a significant increase in the expression of cytokeratin 3/12 markers indicating successful differentiation into CECs. Conclusion The WJMSC cultured on PRGF-enriched Co/SF scaffold demonstrates potential as a viable alternative to conventional CLET, offering a promising strategy for corneal tissue regeneration. [ABSTRACT FROM AUTHOR]

Natural‐derived biomaterials can be used as substrates for the growth, proliferation, and differentiation of cells. In this study, bovine vitreous humor as a biological material was cross‐linked to silk fibroin with different concentration ratios to design a suitable substrate for corneal tissue regeneration. The cross‐linked samples were evaluated with different analyses such as structural, physical (optical, swelling, and degradation), mechanical, and biological (viability, cell adhesion) assays. The results showed that all samples had excellent transparency, especially those with higher silk fibroin content. Increasing the ratio of vitreous humor to silk fibroin decreased mechanical strength and increased swelling and degradation, respectively. There was no significant difference in the toxicity of the samples, and with the increase in vitreous humor ratio, adhesion and cell proliferation increased. Generally, silk fibroin with vitreous humor can provide desirable characteristics as a transparent film for corneal wound healing. [ABSTRACT FROM AUTHOR]

This review discusses recent studies on the combination of nanoparticles (NPs) and biomaterials for the treatment of chronic wounds, especially diabetic foot ulcers (DFUs). This article provides a concise overview of several types of NPs. We will discuss how these NPs possess inherent characteristics that enhance the bioactivity, mechanical strength, tissue adhesion, and antibacterial properties of wound repairing scaffolds. Additionally, we explore their capacity to carry active substances and genes to the wound site. In this context, a comprehensive elucidation of various notable complexities associated with wound repair is provided, alongside corresponding strategies to mitigate them. So that, the adoption of NPs within wound dressings is advocated as a proficient technological approach to address each of these challenges. Furthermore, this article examines several physical and chemical techniques employed by researchers for the incorporation of NPs into scaffolds. [ABSTRACT FROM AUTHOR]

Platelet‐rich fibrin (PRF), which is the rich source of growth factors, has been used as an efficient scaffold in tissue engineering and wound healing. In this study, tannic acid as a green cross‐linker with different concentrations (0.5%, 1%, 5% and 10%) was used to improve the properties of PRF. The cross‐linked gel scaffolds were evaluated by analyses such as scanning electron microscopy, Fourier transform infrared spectroscopy, swelling and degradation, mechanical strength, cell toxicity, cell adhesion and antibacterial test. The results showed that the scaffold structure changes by increasing cross‐linker concentration. The swelling rate decreased from 49% to 5% for the samples without the cross‐linker and with tannic acid (10%), respectively. The degradation percentage for the cross‐linked samples was 8%, which showed a lower degradation rate than the non‐cross‐linked samples (63%). The mechanical strength of the scaffold with the cross‐linker increased up to three times (Young's modulus for the non‐cross linked and the cross‐linked samples: 0.01 and 0.6 MPa, respectively). Cytotoxicity was not observed up to 10% cross‐linker concentration. The cells proliferated well on the cross‐linked scaffolds and also showed a good antibacterial effect. In general, tannic acid can improve the physical and mechanical properties of PRF without negatively affecting its biological properties. [ABSTRACT FROM AUTHOR]

Biological matrices can be modified with cross‐linkers to improve some of their characteristics as scaffolds for tissue engineering. In this study, chemical cross‐linker 1‐Ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide (EDC) was used with different ratios (5, 10, 20, 30, and 40 mM) to improve properties such as mechanical strength, denaturation temperature, and degradability of the acellular fish skin as a biological scaffold for tissue engineering applications. Morphological analysis showed that the use of cross‐linker at low concentrations had no effect on the structure and textiles of the scaffold, while increasing mechanical strength, denaturation temperature, and degradation time. Cytotoxicity and cellular studies showed that the optimal cross‐linker concentration did not significantly affect cell viability as well as cell adhesion. In general, utilising the carbodiimide cross‐linker with the optimal ratio can improve the characteristics and function of the biological tissues such as acellular fish skin. [ABSTRACT FROM AUTHOR]

The decellularization of plant tissues can be one of the design options of scaffolds in tissue engineering. Chemical detergents such as Triton X‐100 and sodium dodecyl sulfate (SDS) in different concentrations were used to decellularize olive leaves as an acellular plant matrix for tissue engineering. The samples were investigated by different analyses such as Hematoxylin and Eosin staining, SEM, tensile strength, swelling, water vapor transmission, and toxicity. The results of staining and toxicity tests showed that the Triton X‐100 decellularized samples at a concentration of 0.1% had the best morphology and the lowest toxicity. Mechanical results showed that the elasticity modulus of acellular samples was significantly reduced compared to normal leaf samples. While swelling rate and water vapor transmission in acellular samples compared to the control sample doubled and tripled, respectively. In general, acellular olive leaf can be suggested as a scaffold for tissue engineering applications. [ABSTRACT FROM AUTHOR]

Natural biomaterials are crucial in ocular tissue engineering because they allow cells to proliferate, differentiate, and stratify while maintaining the typical epithelial phenotype. In this study, membranes as dressings were formed from silk fibroin and collagen (Co) extracted from fish skin and then modified with carbodiimide chemical cross linker in different concentrations. The samples were evaluated by different analyses such as structural, physical (optical, swelling, denaturation temperature, degradation), mechanical, and biological (viability, cell adhesion, immunocytochemistry) assays. The results showed that all membranes have excellent transparency, especially with higher silk fibroin content. Increasing the cross linker concentration and the ratio of silk fibroin to Co increased the denaturation temperature and mechanical strength and, conversely, reduced the degradation rate and cell adhesion. The samples did not show a significant difference in toxicity with increasing cross linker and silk fibroin ratio. In general, samples with a low silk fibroin ratio combined with cross linker can provide desirable properties as a membrane for corneal wound healing. [ABSTRACT FROM AUTHOR]

Dry eye syndrome, as a persist corneal epithelial defect (PED), is an inconvenient ocular disorder that is generally treated by high-dosage, conventional eye drops. Addressing low efficacy and rather restricted bioavailability of the conventional eye drops, drug-eluting contact lenses (CLs) are widely used as alternatives in ophthalmic drug delivery applications. In the present study, a nanofiber-containing ring implant poly (vinyl alcohol) (PVA) hydrogel is designed as a carrier for hyaluronic acid (HA) delivery. hyaluronic acid is physically encapsulated in a nanofiber-containing ring-shaped hydrogel with a 2 mm width that is implanted in the final CLs hydrogel. The designed CL has 59% porosity, 275% swelling ratio and undergoes no weight loss at physiological conditions in14 days. In-vitro release studies were performed on the CLs with and without nanofibers. The results showed that nanofiber incorporation in the designed CL was highly influential in decreasing burst release and supported sustained release of HA over 14 days. In addition, nanofiber incorporation in the designed system strengthened the lens, and the young modulus of the PVA hydrogel increased from 6 to 10 kPa. Cell viability study also revealed no cell cytotoxicity and cell attachment. Overall, the study demonstrated the effective role of nanofibers in the physical strengthening of the CL. Also, the designed system holds promise as a potential candidate for HA delivery over an extended period for treating dry eye syndrome. Graphical Abstract [ABSTRACT FROM AUTHOR]

Blindness of the cornea is the major cause of blindness globally. Many approaches and strategies have been developed to replace or regenerate damaged cornea. Different biomaterials like biopolymeric hydrogels with excellent mechanical & physical properties have been used for the regeneration of corneal tissue. In this review, we focused on using the different types of hydrogels throughout in-vivo studies for the regeneration of corneal epithelial tissue. [ABSTRACT FROM AUTHOR]