Biomimetic Nanofibrous Scaffolds Research Articles

Driving Osteocytogenesis from Mesenchymal Stem Cells in Osteon-like Biomimetic Nanofibrous Scaffolds.

The treatment of critical-sized bone defects caused by tumor removal, skeletal injuries, or infections continues to pose a major clinical challenge. A popular potential alternative solution to autologous bone grafts is a tissue-engineered approach that utilizes the combination of mesenchymal stromal/stem cells (MSCs) with synthetic biomaterial scaffolds. This approach aims to support new bone formation by mimicking many of the biochemical and biophysical cues present within native bone. Regrettably, osteocyte cells, crucial for bone maturation and homeostasis, are rarely produced within MSC-seeded scaffolds, thereby restricting the development of fully mature cortical bone from these synthetic implants. In this work, we have constructed a multimodal scaffold by combining electrospun poly(lactic-co-glycolic acid) (PLGA) fibrous scaffolds with poly(ethylene glycol) (PEG)-based hydrogels that mimic the functional unit of cortical bone, osteon (osteon-mimetic) scaffolds. These scaffolds were decorated with a novel bone morphogenic protein-6 (BMP6) peptide (BMP6p) after our findings revealed that the BMP6p drives higher levels of Smad signaling than the full-length protein counterpart, soluble or when bound to the PEG hydrogel backbone. We show that our osteon-mimetic scaffolds, in presenting concentric layers of BMP6p-PEG hydrogel overlaid on MSC-seeded PLGA nanofibers, promoted the rapid formation of osteocyte-like cells with a phenotypic dendritic morphology, producing early osteocyte markers, including E11/gp38 (E11). Maturation of these osteocyte-like cells was further confirmed by the observation of significant dentin matrix protein 1 (DMP1) throughout our bilayered scaffolds after 3 weeks, even when cultured in a medium without dexamethasone (DEX) or any other osteogenic supplements. These results demonstrate that these osteon-mimetic scaffolds, in presenting biochemical and topographical cues reminiscent of the forming osteon, can drive the formation of osteocyte-like cells in vitro from hBMSCs without the need for any osteogenic factor media supplementation.

Engineering biomimetic scaffolds by combining silk protein nanofibrils and hyaluronic acid

Nanofibrous scaffolds mimicking important features of the native extracellular matrix (ECM) provide a promising strategy for tissue regeneration. However, 3D scaffolds mimicking natural protein nanofibers and bioactive glycosaminoglycans remain poorly developed. In this study, a biomimetic nanofibrous scaffold composed of natural silk protein nanofibers and glycosaminoglycan hyaluronic acid (HA) was developed. HA functionalization significantly improved the hydrophilicity and bioactivity of silk nanofibers (SNFs). SNFs can be assembled into nanofibrous aerogel scaffolds with low density and desirable shapes on a large scale. More importantly, with the assistance of HA, the silk nanofibrous aerogel scaffolds with ultra-high porosity, natural bioactivity, and structural stability in aqueous environment can be fabricated. In the protease/hyaluronidase solution, the SNF scaffolds with 10.0 % HA can maintain their monolithic shape for >3 weeks. The silk nanofibrous scaffolds not only imitate the composition of ECM but also mimic the hierarchical structure of ECM, providing a favorable microenvironment for cell adhesion and proliferation. These results indicate that this structurally and functionally biomimetic system is a promising tissue engineering scaffold.

Silk nanofibrous scaffolds assembled by natural polysaccharide konjac glucomannan

AbstractNatural silk fibroin nanofibers (SNF) have recently attracted great attention in the field of biomaterials due to their excellent biocompatibility, outstanding mechanical properties, and biomimetic nanostructures. However, the poor structural stability of SNF assembly in aqueous conditions remains a major obstacle to their biomedical application. In this work, SNF scaffolds with extracellular matrix‐mimicking architecture and tunable properties were developed by using a small amount of konjac glucomannan (KGM) as a physical adhesive. Fourier transform infrared spectroscopy (FTIR) results revealed that KGM facilitated the formation of hydrogen bond networks between SNF as well as nanofibers/polysaccharide molecules, thereby reinforcing the interconnectivity between SNF. The water stability test showed that SNF scaffolds exhibited good structural stability in water when the mass ratio of KGM/SNF reached 2.5/100. Raising KGM content significantly enhanced the compression strength, modulus, and swelling ratio of the porous scaffold. Whereas, the nanofibrous morphology and porosity of the scaffolds were significantly sacrificed as KGM content exceeded 10% as evidenced by scanning electron microscopy (SEM) results. In vitro, cytocompatibility results also demonstrated the excellent biocompatibility of the biomimetic nanofibrous scaffolds, and the high porosity significantly enhanced cell viability. These results suggest that KGM‐reinforced SNF scaffolds may serve as promising candidates for biomaterial applications.

A novel biomimetic nanofibrous cardiac tissue engineering scaffold with adjustable mechanical and electrical properties based on poly(glycerol sebacate) and polyaniline

Biomaterial tissue engineering scaffolds play a critical role in providing mechanical support, promoting cells growth and proliferation. However, due to the insulation and inappropriate stiffness of most biomaterials, there is an unmet need to engineer a biomimetic nanofibrous cardiac tissue engineering scaffold with tailorable mechanical and electrical properties. Here, we demonstrate for the first time the feasibility to generate a novel type of biocompatible fibrous scaffolds by blending elastic poly(glycerol sebacate) (PGS) and conductive polyaniline (PANI) with the help of a nontoxic carrier polymer, poly (vinyl alcohol) (PVA). Aligned and random PGS/PANI scaffolds are successfully obtained after electrospinning, cross-linking, water and ethanol wash. Incorporating of different concentrations of PANI into PGS fibers, the fibrous sheets show enhanced conductivity and slower degradation rates while maintaining the favorable hemocompatibility. The elastic modulus of the PGS/PANI scaffolds is in the range of 0.65–2.18 MPa under wet conditions, which is similar to that of natural myocardium. All of these fibrous mats show good cell viability and were able to promote adhesion and proliferation of H9c2 cells. Furthermore, the in vivo host responses of both random and aligned scaffolds confirm their good biocompatibility. Therefore, these PGS/PANI scaffolds have great potential for cardiac tissue engineering.

Asymmetric fabrication and in vivo evaluation of the wound healing potency of electrospun biomimetic nanofibrous scaffolds based on collagen crosslinked modified-chitosan and graphene oxide quantum dot nanocomposites.

Asymmetric scaffolds were developed through electrospinning by utilizing biocompatible materials for effective wound healing applications. First of all, the chitosan surface was modified with decanoyl chloride and crosslinked with collagen to synthesize collagen crosslinked modified-chitosan (CG-cross-CS-g-Dc). Then, the asymmetric scaffolds were fabricated through electrospinning, where the top layer was a monoaxial nanofiber of the PCL/graphene oxide quantum dot (GOQD) nanocomposite and the bottom layer was a coaxial nanofiber having PCL in the core and the CG-cross-CS-g-Dc/GOQD nanocomposite in the shell layer. The formation of monoaxial (∼130 ± 50 nm) and coaxial (∼320 ± 40 nm) nanofibers was confirmed by transmission electron microscopy (TEM). The presence of GOQDs contributed to antioxidant and antimicrobial efficacy. These scaffolds showed substantial antibacterial activity against the common wound pathogens Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The scaffolds exhibited excellent cytocompatibility (MTT assay) and anti-inflammatory behaviour as analysed via the cytokine assay and biochemical analysis. The in vivo wound healing potential of the nanofibrous scaffolds was assessed with full-thickness excisional wounds in a rat model. The scaffolds accelerated the re-epithelialization as well as the collagen deposition, thereby facilitating the wound healing process in a very short span of time (10 days). Both in vitro and in vivo analyses thus provide a compelling argument for the use of these scaffolds as therapeutic biomaterials and their suitability for application in rapid wound regeneration and repair.

Electrospun Biomimetic Nanofibrous Scaffolds: A Promising Prospect for Bone Tissue Engineering and Regenerative Medicine.

Skeletal-related disorders such as arthritis, bone cancer, osteosarcoma, and osteoarthritis are among the most common reasons for mortality in humans at present. Nanostructured scaffolds have been discovered to be more efficient for bone regeneration than macro/micro-sized scaffolds because they sufficiently permit cell adhesion, proliferation, and chemical transformation. Nanofibrous scaffolds mimicking artificial extracellular matrices provide a natural environment for tissue regeneration owing to their large surface area, high porosity, and appreciable drug loading capacity. Here, we review recent progress and possible future prospective electrospun nanofibrous scaffolds for bone tissue engineering. Electrospun nanofibrous scaffolds have demonstrated promising potential in bone tissue regeneration using a variety of nanomaterials. This review focused on the crucial role of electrospun nanofibrous scaffolds in biological applications, including drug/growth factor delivery to bone tissue regeneration. Natural and synthetic polymeric nanofibrous scaffolds are extensively inspected to regenerate bone tissue. We focused mainly on the significant impact of nanofibrous composite scaffolds on cell adhesion and function, and different composites of organic/inorganic nanoparticles with nanofiber scaffolds. This analysis provides an overview of nanofibrous scaffold-based bone regeneration strategies; however, the same concepts can be applied to other organ and tissue regeneration tactics.

Electrospun multifaceted nanocomposites for promoting angiogenesis in curing burn wound

Burn wound care always remains a herculean task owing to its myriad of complications following injury. The current work describes the development of a biodegradable 3D framework fabricated from PVA, gelatin, chitosan polymers embedded with ferulic acid and resveratrol with direct influence on cellular recruitment and activation, without altering the temporal sequence of the healing process. The structural analysis of the scaffold revealed randomly oriented highly interconnected porous structured fibers which favored cell adhesion, migration and proliferation. Furthermore, the physico-chemical characterisation elucidated good compatibility of the drugs with the scaffolds and in-vitro release profile exhibited the sustained release of bioactive components up to 96 h endorsing the fabricated nanofibrous scaffold as a controlled drug delivery system. The drug incorporated nanofibrous construct exhibited an extensive potential in augmenting angiogenesis and cell migration (82% wound closure at 8 h) in in-vitro studies. The biotherapeutic nanofibrous scaffold enhanced the restoration of wounded tissue in in-vivo models. Thus, the present study strides way for developing, biomimetic nanofibrous scaffolds with sequential drug delivery for chronic wound management.

Multifunctional Biomimetic Nanofibrous Scaffold Loaded with Asiaticoside for Rapid Diabetic Wound Healing.

Diabetes mellitus is a chronic disease with a high mortality rate and many complications. A non-healing diabetic foot ulcer (DFU) is one the most serious complications, leading to lower-extremity amputation in 15% of diabetic patients. Nanofibers are emerging as versatile wound dressing due to their unique wound healing properties, such as a high surface area to volume ratio, porosity, and ability to maintain a moist wound environment capable of delivering sustained drug release and oxygen supply to a wound. The present study was aimed to prepare and evaluate a polyvinyl alcohol (PVA)–sodium alginate (SA)–silk fibroin (SF)-based multifunctional nanofibrous scaffold loaded with asiaticoside (AT) in diabetic rats. The SEM findings showed that fibers’ diameters ranged from 100–200 nm, and tensile strengths ranged from 12.41–16.80 MPa. The crosslinked nanofibers were sustained AT over an extended period. The MTT and scratch assay on HaCat cells confirmed low cytotoxicity and significant cell migration, respectively. Antimicrobial tests revealed an excellent anti-microbial efficacy against P. aeruginosa and S. aureus bacteria. In-vivo study demonstrated better wound healing efficacy in diabetic rats. In addition, the histopathological studies showed its ability to restore the normal structure of the skin. The present study concluded that developed multifunctional nanofibers have a great potential for diabetic wound healing applications.

Design and development of biomimetic electrospun sulphonated polyether ether ketone nanofibrous scaffold for bone tissue regeneration applications: in vitro and in vivo study

Bone defect restoration remains challenging in orthopedic medical practices. In this study an attempt is carried out to probe the use of new biomimetic SPEEK (sulfonated polyether ether ketone) based nanofibrous scaffold to deliver amine functionalized hydroxyapatite nanoparticles loaded resveratrol for its potent functionality in osteogenic differentiation. SPEEK polymer with reactive functional group SO3H was synthesized through process of sulphonation reaction. Amine functionalized nanoparticles with protonated amino groups revamp the molecular interaction by the formation of hydrogen bonds that in turn intensify the bioactivity of the nanofibrous scaffold. Osteoconductive functionalized nanohydroxyapatite enhances the cell proliferation and osteogenicity with improved cell attachment and spreading. The results of FT-IR, XRD, Carbon-Silica NMR and EDX analysis confirmed the amine functionalization of the hydroxyapatite nanoparticles. Surface morphological analysis of the fabricated nanofibers through SEM and AFM analysis shows vastly interconnected porous structure that mimics the bone extracellular matrix, which enhances the cell compatibility. Cell adhesion and live dead assay of the nanoscaffolds express less cytotoxicity. Mineralization and alkaline phosphatase assay establish the osteogenic differentiation of the nanofibrous scaffold. The in vitro biocompatibility studies reveal that the fabricated scaffold was osteo-compatible with MG63 cell lines. Hemocompatibility study further proved that the designed biomimetic nanofibrous scaffold was highly suitable for bone tissue engineering. The results of in vivo analysis in zebrafish model for the fabricated nanofibers demonstrated significant increase in the caudal fin regeneration indicating mineralization of osteoblast. Thus, the commending results obtained instigate the potentiality of the composite nanofibrous scaffold as an effective biomimetic substrate for bone tissue regeneration.

Driving Osteocytogenesis from Mesenchymal Stem Cells in Osteon-Like Biomimetic Nanofibrous Scaffolds

Driving Osteocytogenesis from Mesenchymal Stem Cells in Osteon-Like Biomimetic Nanofibrous Scaffolds

Electrospun scaffold for bone regeneration

The growing trend of bone disorders often caused by accidental injury coupled with aging increasing aging population demands more effective therapeutic intervention. Bone tissue engineering is considered a unique method that provides functional bone grafts by combining biomaterial, cells, and signaling factors and can be a promising alternative to the conventional bone grafts used for bone defect treatment. However, the fabrication of a scaffold matrix with nanofeature architecture mimicking bone tissue is one of the significant challenges that limits its clinical application so far. In this context, electrospinning generating biomimetic nanofibrous scaffold structures is a potential technique that results in an excellent micro-environment for the cells to attach, migrate, proliferate, and finally differentiate in comparison to scaffolds fabricated by traditional methods and hence widely used mainly in the last decade. Although having several advantages of electrospun scaffolds, cell infiltration and mechanical strength of the scaffolds are the significant issues that need to be addressed for bone tissue engineering. Numerous concepts or strategies applied during or after electrospinning to overcome these limitations are the main focus points of the current review. This review highlights the current research related to electrospinning techniques used to fabricate bone scaffold and the influence of critical process parameters on nanofiber formation. The various recently reported advanced scaffold fabrication techniques and their advantages when combined with electrospinning process has been presented to address the limitation associated with the bone tissue engineered scaffold fabrication, which may pave the way for the fabrication of scaffold for clinical grade bone graft development in future.

Preparation and characterization of aspirin-loaded polylactic acid/graphene oxide biomimetic nanofibrous scaffolds

The combination of biomimetic scaffolds and nano drug delivery has been proposed to be an effective solution to the inherent limitations of the former in regulating cell behavior and bone tissue regeneration. Herein, a series of three-dimensional (3D) aspirin-loaded polylactic acid/graphene oxide (PLA/GO) porous biomimetic nanofibrous composite scaffolds (PBNCSs) was successfully prepared by phase separation. Results showed that the PLA/GO scaffolds have a biomimetic nanofibrous porous structure and a thin GO film covering the PLA nanofibers, which endows the latter with significantly improved hydrophilicity. Close interactions were noted in the GO–PLA interface. GO reduced the mechanical properties of the composite scaffolds but increased their thermal stability. The water absorption rate increased from 12.5% to 206.81% as the GO content increased from 0 to 5%. Addition of GO improved the deposition rate and amount of hydroxyapatite on the scaffolds. Overall, the PLA/GO PBNCSs demonstrated good cytocompatibility and sustained-release performance.

Biomimetic Nanofibrous 3D Materials for Craniofacial Bone Tissue Engineering.

Repair of large bone defects using biomaterials-based strategies has been a significant challenge due to the complex characteristics required for tissue regeneration, especially in the craniofacial region. Tissue engineering strategies aimed at restoration of function face challenges in material selection, synthesis technique, and choice of bioactive factor release in combination with all aforementioned facets. Biomimetic nanofibrous (NF) scaffolds are attractive vehicles for tissue engineering due to their ability to promote endogenous bone regeneration by mimicking the shape and chemistry of natural bone extracellular matrix (ECM). To date, several techniques for generation of biomimetic NF scaffolds have been discovered, each possessing several advantages and drawbacks. This spotlight highlights two of the more popular techniques for biomimetic NF scaffold synthesis: electrospinning and thermally-induced phase separation (TIPS), covering development from inception in each technique as well as discussing the most recent innovations in each fabrication method.

Fabrication and characterization of P(3HB-co-4HB)/gelatine biomimetic nanofibrous scaffold for tissue engineering application

This study focussed on developing a hybrid P(3HB-co-4HB)/gelatine nanofibre with an enhanced wettability and biocompatibility properties while retaining its desired properties as biodegradable patch for tissue engineering application through electrospinning technique. Both copolymer and gelatine were individually optimized for its concentration, process parameter and voltage. Upon optimization, two versions of hybrid P(3HB-co-4HB)/gelatine nanofibre scaffolds were prepared by layering the copolymer and gelatine, namely PG (double - layer) and PGP (triple - layer). These hybrid scaffolds produced were further crosslink using glutaraldehyde vapour and were characterized for its fibre morphology, wettability, chemical and biological properties. The nanofibre diameter obtained was in between 330 nm to 250 nm for P(3HB-co-4HB) and both hybrid P(3HB-co-4HB)/gelatine. The expression of amino acid, carbonyl group and presence of glutaraldehyde on nanofibre was detected using ATR-FTIR analysis. The PG shows to exhibit better hydrophilic property compared to PGP and P(3HB-co-4HB). However, based on the stability testing was carried out, it revealed that PG has low solution stability compared to PGP which indicates PGP nanofibre scaffolds reaffirms a good water-resistant property. Meanwhile, the MTS assay has shown that mouse fibroblast cell L929 proliferated well on both PG and PGP compared to pure P(3HB-co-4HB) nanofibre scaffolds, evidenced by an increased cell number from 3.04 × 105 cells/mL to 3.37 × 105 cells/mL. The results have collectively shown the incorporation of small amount of fish gelatine has improved the overall properties of hybrid nanofibre scaffolds. The PGP shows the potential candidates for medical application due to its stability property in solution and has comparable property with PG.

Nanofibrous vascular scaffold prepared from miscible polymer blend with heparin/stromal cell-derived factor-1 alpha for enhancing anticoagulation and endothelialization

There is an urgent clinical demand to develop a functional small diameter vascular graft with long-term patency, which mainly relies on the anticoagulation and endothelialization of the vascular graft. In addition, improved degradation of vascular graft provides more space for cell infiltration and facilitates remodeling of blood vessel. In this study, an elastic and biomimetic nanofibrous vascular scaffold with improved degradability was prepared by adding poly(lactic-co-glycolic acid) (PLGA) into the poly(L-lactic acid) (PLLA)/poly(L-lactide-co-ε-caprolactone) (PLCL) blend using thermally induced phase separation (TIPS) technique. The incorporation of PLGA also improved the hydrophilicity of the composite scaffold. Then the vascular scaffold was surface modified by combination of heparin and stromal cell-derived factor-1 alpha (SDF-1α). The results of whole blood clotting kinetics and plasma recalcification profiles indicated that heparinized modification significantly enhanced the anticoagulation of vascular scaffold. In vitro cell culture assays demonstrated the immobilized SDF-1α facilitated recruitment of endothelial progenitor cells (EPCs), migration and proliferation of mature endothelial cells, human umbilical vein endothelial cells (HUVECs), and expression of VE-cadherin/CD144 and endothelial nitric oxide synthase (eNOS) genes in HUVECs, thereby accelerating the endothelialization of the modified vascular scaffold. Besides, the nanofibrous vascular scaffold modified with heparin and SDF-1α inhibited the proliferation of human vascular smooth muscle cells (HVSMCs). Therefore, the phase separated nanofibrous vascular scaffold modified with heparin and SDF-1α shows the promising in vitro performance as a functional small diameter vascular graft.

Electrospun polycaprolactone/hydroxyapatite/ZnO nanofibers as potential biomaterials for bone tissue regeneration.

Fabricating a bioartificial bone graft possessing structural, mechanical and biological properties mimicking the real bone matrix is a major challenge in bone tissue engineering. Moreover, the developed materials are prone to microbial invasion leading to biomaterial centered infections which might limit their clinical translation. In the present study, biomimetic nanofibrous scaffolds of Poly ɛ-caprolactone (PCL)/nano-hydroxyapatite (nHA) were electrospun with 1wt%, 5wt%, 10wt%, 15wt% and 30wt% of zinc oxide (ZnO) nanoparticles in order to understand the optimal concentration range of (ZnO) nanoparticles balancing both biocompatibility and osteoregeneration. The developed nanofibrous scaffolds were successfully characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDAX), contact angle, fourier transform infrared spectroscopy (FTIR), wide-angle X-Ray diffraction (WAXD), brunaueremmett Teller (BET) surface area and tensile testing. Biocompatibility of the developed scaffolds at in vitro level was evaluated by culturing MG-63 cells and investigating the impact on cell viability, proliferation, protein adsorption, alkaline phosphatase (ALP) activity and biomineralization. The PCL/nHA scaffolds exhibited a 1.2-fold increase in cell viability and proliferation, while incorporation of ZnO nanoparticles to PCL/nHA imparted antimicrobial activity to the scaffolds with a progressive increase in the antimicrobial efficacy with increasing ZnO concentration. The results of cell viability were supported by ALP activity and mineralization assay, wherein, PCL/nHA/ZnO scaffolds showed higher ALP activity and better mineralization capacity as compared to pristine PCL. Although, the PCL/nHA/ZnO scaffolds with 10, 15 and 30wt% of ZnO particles exhibited superior antimicrobial efficacy against both gram-negative (E. coli) and gram-positive (S. aureus) bacteria, a significant decrease in the cell viability and mechanical properties was observed at higher concentrations of ZnO namely 15 and 30%. Amongst the various ZnO concentrations studied optimal cell viability, antimicrobial effect and mechanical strength were observed at 10wt.% ZnO concentration. Thus, the present study revealed that the biomimetic tri-component PCL/nHA/ZnO scaffolds with ZnO concentration range of ≤ 10% could be ideal for achieving optimal biocompatibility (cell proliferation, biomineralization, and antimicrobial capacity) and mechanical stability thus making it a promising biomaterial substrate for bone tissue regeneration.

The potential of biomimetic nanofibrous electrospun scaffold comprising dual component for bone tissue engineering

Oils play a putative choice for alleviating various symptoms associated with bone-related disorders. In this present study, polyurethane (PU) scaffold encompassing with Mahua oil (MO) and propolis (PP) were developed using the electrospinning technique. Morphological analysis showed the reduction in the diameter of the electrospun scaffold with blending of MO and MO/PP into the PU matrix. The strong interactions between PU, MO, and PP were evident through the infrared spectrum and thermal analysis. The wettability results showed the hydrophobic nature in electrospun PU/MO scaffold and hydrophilic behavior in electrospun PU/MO/PP scaffold. Mechanical testing indicated the enhancement in the strength of the PU due to the addition of MO and PP. Moreover, the fabricated scaffolds exhibited nontoxicity, low hemoglobin release and improved blood clotting time as evident in the coagulation studies. The cell proliferation studies showed the enhanced fibroblast cell adhesion in the developed nanocomposites than the pristine PU. Hence, the fabricated PU scaffolds blended with MO and PP having desirable properties can serve as a valuable candidate for bone tissue repair.

Type I collagen peptides and nitric oxide releasing electrospun silk fibroin scaffold: A multifunctional approach for the treatment of ischemic chronic wounds.

Biomimetic nanofibrous scaffolds targeting multiple dysfunctional processes provide a multi-pronged strategy to restore functions and regenerate the damaged tissue. This study investigates a strategy of combining a regenerative component, Type I collagen Peptide (CP), along with a nitric oxide donor, S-Nitrosoglutathione (GSNO), in the form of nanofibrous scaffold to address the non-healing diabetic ulcer. Silk Fibroin-Polyvinyl alcohol (SF-PVA) nanofibrous scaffold is used as a carrier for delivering functional moieties. The developed nanofibrous electrospun mats (SF-PVA, CP-SF-PVA, and CP-GSNO-SF-PVA) showed continuous, bead-less and randomly oriented fibers with highly porous morphology. The in vitro biocompatibility was assessed by MTT assay, DAPI-Rhodamine 123 and FITC-Phalloidin imaging studies. CP-GSNO-SF-PVA nanofibrous scaffold showed a high degree of cell attachment, spreading of F-actin with viable cell morphology and appreciable inter-cellular connection. Thus the study showed that the proliferation of fibroblast cells are mainly facilitated by the presence of collagen peptide in the nanofibrous matrix. Griess assay demonstrated immediate release of NO for a day from the developed multifunctional scaffold. These results demonstrate the in vitro efficacy of CP-GSNO and indicate the opportunity of CP-GSNO-SF-PVA nanofibrous scaffold for the treatment of ischemic non-healing ulcers.

Hybrid scaffolds enhanced by nanofibers improve in vitro cell behavior for tissue regeneration

To construct a biomimetic scaffold with a nanoscale structure similar to that of natural tissue, the objective of this work was to prepare three-dimensional (3D) porous hybrid scaffolds based on gelatin and bacterial cellulose nanofibers for tissue regeneration. The nanofibrous structure, water absorption, and compressive mechanical properties of the scaffolds were studied. The hybrid scaffolds not only give a sufficiently porous structure for efficient nutrient transport and vascularization, but also provide the nanofibrous structure and improve the roughness of the scaffold pore walls. The hybrid scaffolds also exhibit higher modulus as stiffness compared to the pure gelatin scaffold. The viability and morphology of Pig iliac endothelial cells (PIECs) cultured on the 3D scaffolds were examined. PIECs adhered and proliferated better on the stiff hybrid scaffold with nanofibers compared to the soft gelatin scaffold without nanofibers. The results addressed the effect of the nanofibers and the stiffness of scaffolds on cell behavior, and the biomimetic nanofibrous hybrid scaffolds would be highly favorable/desired for tissue regeneration, e.g., skin and urethral regeneration.

Differentiation of Menstrual Blood Stem Cells into Keratinocyte-Like Cells on Bilayer Nanofibrous Scaffold.

Skin tissue engineering is a high-throughput technology to heal the wounds. Already, considerable advances have been achieved using stem cells for wound healing applications. Menstrual blood stem cell (MenSC) is an available and accessible source of stem cells that have differentiation potential into a wide range of lineages like keratinocytes. Extracellular matrix like substratum plays an impressive role in skin regeneration as an attachment site for stem cells by transmitting the bioactive signals and provoking stem cells to differentiate into keratinocyte lineage. The biomimetic nanofibrous scaffold especially in bilayer format has been extensively utilized to develop skin equivalents. This chapter explains detailed protocols of keratinocyte differentiation of MenSCs on bilayer scaffold comprising amniotic membrane and fibroin nanofibers. The isolated MenSCs are seeded on the nanofibers and subsequently differentiated into keratinocyte lineage in co-culture with foreskin-derived keratinocytes. Immunofluorescence staining is used to evaluate the development of seeded MenSCs in bilayer scaffold into keratinocyte-like cells.