Acellular Scaffolds Research Articles

A scalable corneal xenograft platform: simultaneous opportunities for tissue engineering and circular economic sustainability by repurposing slaughterhouse waste.

Introduction: Corneal disease is a leading cause of blindness globally that stems from various etiologies. High-throughput platforms that can generate substantial quantities of corneal grafts will be invaluable in addressing the existing global demand for keratoplasty. Slaughterhouses generate substantial quantities of underutilized biological waste that can be repurposed to reduce current environmentally unfriendly practices. Such efforts to support sustainability can simultaneously drive the development of bioartificial keratoprostheses. Methods: Scores of discarded eyes from the prominent Arabian sheep breeds in our surrounding region of the United Arab Emirates (UAE) were repurposed to generate native and acellular corneal keratoprostheses. Acellular corneal scaffolds were created using a whole-eye immersion/agitation-based decellularization technique with a widely available, eco-friendly, and inexpensive 4% zwitterionic biosurfactant solution (Ecover, Malle, Belgium). Conventional approaches like DNA quantification, ECM fibril organization, scaffold dimensions, ocular transparency and transmittance, surface tension measurements, and Fourier-transform infrared (FTIR) spectroscopy were used to examine corneal scaffold composition. Results: Using this high-throughput system, we effectively removed over 95% of the native DNA from native corneas while retaining the innate microarchitecture that supported substantial light transmission (over 70%) after reversing opacity, a well-established hallmark of decellularization and long-term native corneal storage, with glycerol. FTIR data revealed the absence of spectral peaks in the frequency range 2849cm-1 to 3075cm-1, indicating the effective removal of the residual biosurfactant post-decellularization. Surface tension studies confirmed the FTIR data by capturing the surfactant's progressive and effectual removal through tension measurements ranging from approximately 35mN/m for the 4% decellularizing agent to 70mN/m for elutes highlighting the effective removal of the detergent. Discussion: To our knowledge, this is the first dataset to be generated outlining a platform that can produce dozens of ovine acellular corneal scaffolds that effectively preserve ocular transparency, transmittance, and ECM components using an eco-friendly surfactant. Analogously, decellularization technologies can support corneal regeneration with attributes comparable to native xenografts. Thus, this study presents a simplified, inexpensive, and scalable high-throughput corneal xenograft platform to support tissue engineering, regenerative medicine, and circular economic sustainability.

Proliferation kinetics and mineralization properties of MC3T3‐E1 cells on whey protein isolate scaffolds for bone tissue regeneration

AbstractThe purpose of the study is to assess the influence of scaffold composition and properties on the cellular proliferation and scaffold mineralization on a whey protein isolate (WPI) scaffold. Scaffolds of varying concentrations of WPI, calcium chloride, and amylopectin are seeded with cells, and growth curves are constructed from cell density measurements following incubation. Non‐linear regression yields kinetic growth parameters which are compared for quantitative assessment of scaffold performance. Scaffolds show biocompatibility and the ability to sustain a culture for the length of the study. For up to 14 days, the data are well described by exponential growth. Thereafter, saturation behavior appears, and the data fit well to a sigmoidal model. The seeding efficiency improves with increasing WPI concentration, peaking at 5 mM CaCl2, and decreases with added amylopectin. The growth constant is almost independent of scaffold composition, with possible increases with added CaCl2 and amylopectin. The retardation constant is independent of composition. Scaffolds cultured in differentiation and mineralization conditions, shows development of a mineralized matrix both on acellular scaffold surfaces and in osteoblast cultures. The ability of the unmodified WPI gel surfaces to promote the growth and differentiation of a model preosteoblast provides valuable trends and concentration effects for further scaffold design.

A Decellularized Uterine Endometrial Scaffold Enhances Regeneration of the Endometrium in Rats.

Partial or whole regeneration of the uterine endometrium using extracellular matrix (ECM)-based scaffolds is a therapeutic strategy for uterine infertility due to functional and/or structural endometrial defects. Here, we examined whether the entire endometrium can be regenerated circumferentially using an acellular ECM scaffold (decellularized endometrial scaffold, DES) prepared from rat endometrium. We placed a silicone tube alone to prevent adhesions or a DES loaded with a silicone tube into a recipient uterus in which the endometrium had been surgically removed circumferentially. Histological and immunofluorescent analyses of the uteri one month after tube placement revealed more abundant regenerated endometrial stroma in the uterine horns treated with tube-loaded DES compared to those treated with a tube alone. Luminal and glandular epithelia, however, were not fully recapitulated. These results suggest that DES can enhance the regeneration of endometrial stroma but additional intervention(s) are needed to induce epithelization. Furthermore, the prevention of adhesions alone allowed the endometrial stroma to regenerate circumferentially even without a DES, but to a lesser degree than that with a DES. The use of a DES together with the prevention of adhesions may be beneficial for efficient endometrial regeneration in the uterus that is largely deficient of endometrium.

Decellularization of the human urethra for tissue engineering applications.

Recently, several scaffolds have been introduced for urethral tissue engineering. However, acellular human urethral scaffold harvested from deceased donors may provide significant advantages compared to synthetic, composite, or other biological scaffolds. This study aims to develop the protocol for decellularization of the human urethra that preserves substantial extracellular matrix (ECM) components, which are essential for subsequent recellularization mimicking the natural environment of the native ECM. A total of 12 human urethras were harvested from deceased donors. An equal part of every harvested urethra was used as a control sample for analyses. The protocol design was based on the enzyme-detergent-enzyme method. Trypsin and Triton X-100 were used to remove cells, followed by DNase treatment to remove DNA residues. Subsequently, the specimens were continually rinsed in deionized water for seven days. The efficiency of decellularization was determined by histochemistry, immunohistochemical staining, scanning electron microscopy (SEM), and DNA quantification. Histological analysis confirmed cell removal and preservation of urethral structure after decellularization. The preservation of collagen IV and fibronectin was confirmed by histologic examination and immunohistochemical staining. SEM confirmed the maintenance of the ultrastructural architecture of ECM and fibers. DNA content in decellularized urethra was significantly lower compared to the native sample (P < 0.001), and so the criteria for decellularized tissue were met. Cytotoxicity analysis data showed that the matrix-conditioned medium did not contain soluble toxins and had no significant inhibitory effect on cell proliferation, providing evidence that the decellularized samples are not toxic. This study demonstrates the feasibility of the enzyme-detergent-enzyme-based decellularization protocol for removing cellular components and maintaining urethral ECM and its ultrastructure. Moreover, obtained results provide solid ground for recellularization and urethral tissue engineering, which will follow.

Development and In Vivo Assessment of an Injectable Cross-Linked Cartilage Acellular Matrix-PEG Hydrogel Scaffold Derived from Porcine Cartilage for Tissue Engineering.

The cartilage acellular matrix (CAM) derived from porcine cartilage, which does not induce significant inflammation and provides an environment conducive for cell growth and differentiation, is a promising biomaterial candidate for scaffold fabrication. However, the CAM has a short period in vivo, and the in vivo maintenance is not controlled. Therefore, this study is aimed at developing an injectable hydrogel scaffold using a CAM. The CAM is cross-linked with a biocompatible polyethylene glycol (PEG) cross-linker to replace typically used glutaraldehyde (GA) cross-linker. The cross-linking degree of cross-linked CAM by PEG cross-linker (Cx-CAM-PEG) according to the ratios of the CAM and PEG cross-linker is confirmed by contact angle and heat capacities measured by differential scanning calorimetry. The injectable Cx-CAM-PEG suspension exhibits controllable rheological properties and injectability. Additionally, injectable Cx-CAM-PEG suspensions with no free aldehyde group are formed in the in vivo hydrogel scaffold almost simultaneously with injection. In vivo maintenance of Cx-CAM-PEG is realized by the cross-linking ratio. The in vivo formed Cx-CAM-PEG hydrogel scaffold exhibits certain host-cell infiltration and negligible inflammation within and near the transplanted Cx-CAM-PEG hydrogel scaffold. These results suggest that injectable Cx-CAM-PEG suspensions, which are safe and biocompatible in vivo, represent potential candidates for (pre-)clinical scaffolds.

2023 TERMIS – AMERICAS Conference &amp; Exhibition Boston Marriott Copley Place April 11–14, 2023

2023 TERMIS – AMERICAS Conference &amp; Exhibition Boston Marriott Copley Place April 11–14, 2023

Evaluation of decellularization process for developing osteogenic bovine cancellous bone scaffolds in-vitro.

Current immunological issues in bone grafting regarding the transfer of xenogeneic donor bone cells into the recipient are challenging the industry to produce safer acellular natural matrices for bone regeneration. The aim of this study was to investigate the efficacy of a novel decellularization technique for producing bovine cancellous bone scaffold and compare its physicochemical, mechanical, and biological characteristics with demineralized cancellous bone scaffold in an in-vitro study. Cancellous bone blocks were harvested from a bovine femoral head (18-24 months old) subjected to physical cleansing and chemical defatting, and further processed in two ways. Group I was subjected to demineralization, while Group II underwent decellularization through physical, chemical, and enzymatic treatments. Both were then freeze-dried, and gamma radiated, finally producing a demineralized bovine cancellous bone (DMB) scaffold and decellularized bovine cancellous bone (DCC) scaffold. Both DMB and DCC scaffolds were subjected to histological evaluation, scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), fourier-transform infrared spectroscopy (FTIR), quantification of lipid, collagen, and residual nucleic acid content, and mechanical testing. The osteogenic potential was investigated through the recellularization of scaffolds with human osteoblast cell seeding and examined for cell attachment, proliferation, and mineralization by Alizarin staining and gene expression. DCC produced a complete acellular extracellular matrix (ECM) with the absence of nucleic acid content, wider pores with extensive interconnectivity and partially retaining collagen fibrils. DCC demonstrated a higher cell proliferation rate, upregulation of osteogenic differentiation markers, and substantial mineralized nodules production. Our findings suggest that the decellularization technique produced an acellular DCC scaffold with minimal damage to ECM and possesses osteogenic potential through the mechanisms of osteoconduction, osteoinduction, and osteogenesis in-vitro.

Cirrhotic Liver Sustains In Situ Regeneration of Acellular Liver Scaffolds after Transplantation into G-CSF-Treated Animals.

Acellular liver scaffolds (ALS) produced by decellularization have been successfully explored for distinct regenerative purposes. To date, it is unknown whether transplanted ALSs are affected by cirrhotic livers, either becoming cirrhotic themselves or instead remaining as a robust template for healthy cell growth after transplantation into cirrhotic rats. Moreover, little is known about the clinical course of recipient cirrhotic livers after ALS transplantation. To address these questions, we transplanted ALSs into cirrhotic rats previously treated with the granulocyte colony-stimulating factor. Here, we report successful cellular engraftment within the transplanted ALSs at 7, 15, and 30 days after transplantation. Recellularization was orchestrated by liver tissue cell activation, resident hepatocytes and bile duct proliferation, and an immune response mediated by the granulocyte components. Furthermore, we showed that transplanted ALSs ensured a pro-regenerative and anti-inflammatory microenvironment, attracted vessels from the host cirrhotic tissue, and promoted progenitor cell recruitment. ALS transplantation induced cirrhotic liver regeneration and extracellular matrix remodeling. Moreover, the transplanted ALS sustained blood circulation and attenuated alterations in the ultrasonographic and biochemical parameters in cirrhotic rats. Taken together, our results confirm that transplanted ALSs are not affected by cirrhotic livers and remain a robust template for healthy cell growth and stimulated cirrhotic liver regeneration.

Effect of different decellularization protocols on reendothelialization with human cells for a perfused renal bioscaffold of the rat

BackgroundScaffolds for tissue engineering can be received by whole organ decellularization while maintaining the site-specific extracellular matrix and the vascular tree. One among other decellularization techniques is the perfusion-based method using specific agents e.g. SDS for the elimination of cellular components. While SDS can disrupt the composition of the extracellular matrix and impair the adherence and growth of site-specific cells there are indications that xenogeneic cell types may benefit from protein denaturation by using higher detergent concentrations. The aim of this work is to investigate the effect of two different SDS-concentrations (i.e. 0.66% and 3%) on the ability of human endothelial cells to adhere and proliferate in an acellular rat kidney scaffold.Material and methodsAcellular rat kidney scaffold was obtained by perfusion-based decellularization through the renal artery using a standardized protocol including SDS at concentrations of 0.66% or 3%. Subsequently cell seeding was performed with human immortalized endothelial cells EA.hy 926 via the renal artery. Recellularized kidneys were harvested after five days of pressure-controlled dynamic culture followed sectioning, histochemical and immunohistochemical staining as well as semiquantitative analysis.ResultsEfficacy of decellularization was verified by absence of cellular components as well as preservation of ultrastructure and adhesive proteins of the extracellular matrix. In semiquantitative analysis of recellularization, cell count after five days of dynamic culture more than doubled when using the gentle decellularization protocol with a concentration of SDS at 0.66% compared to 3%. Detectable cells maintained their endothelial phenotype and presented proliferative behavior while only a negligible fraction underwent apoptosis.ConclusionRecellularization of acellular kidney scaffold with endothelial cells EA.hy 926 seeded through the renal artery benefits from gentle decellularization procedure. Because of that, decellularization with a SDS concentration at 0.66% should be preferred in further studies and coculture experiments.

Acellular fish skin for wound healing.

Fish skin grafting as a new skin substitute is currently being used in clinical applications. Acceleration of the wound healing, lack of disease transmission, and low cost of the production process can introduce fish skin as a potential alternative to other grafts. An appropriate decellularization process allows the design of 3D acellular scaffolds for skin regeneration without damaging the morphology and extracellular matrix content. Therefore, the role of decellularization processes is very important to maintain the properties of fish skin. In this review article, recent studies on various decellularization processes as well as biological, physical, and mechanical properties of fish skin and its applications with therapeutic effects in wound healing were investigated.

Accelular nanofibrous bilayer scaffold intrapenetrated with polydopamine network and implemented into a full-thickness wound of a white-pig model affects inflammation and healing process

Treatment of complete loss of skin thickness requires expensive cellular materials and limited skin grafts used as temporary coverage. This paper presents an acellular bilayer scaffold modified with polydopamine (PDA), which is designed to mimic a missing dermis and a basement membrane (BM). The alternate dermis is made from freeze-dried collagen and chitosan (Coll/Chit) or collagen and a calcium salt of oxidized cellulose (Coll/CaOC). Alternate BM is made from electrospun gelatin (Gel), polycaprolactone (PCL), and CaOC. Morphological and mechanical analyzes have shown that PDA significantly improved the elasticity and strength of collagen microfibrils, which favorably affected swelling capacity and porosity. PDA significantly supported and maintained metabolic activity, proliferation, and viability of the murine fibroblast cell lines. The in vivo experiment carried out in a domestic Large white pig model resulted in the expression of pro-inflammatory cytokines in the first 1–2 weeks, giving the idea that PDA and/or CaOC trigger the early stages of inflammation. Otherwise, in later stages, PDA caused a reduction in inflammation with the expression of the anti-inflammatory molecule IL10 and the transforming growth factor β (TGFβ1), which could support the formation of fibroblasts. Similarities in treatment with native porcine skin suggested that the bilayer can be used as an implant for full-thickness skin wounds and thus eliminate the use of skin grafts.

What's New in Sports Medicine.

What's New in Sports Medicine.

Angiogenesis and Re-endothelialization in decellularized scaffolds: Recent advances and current challenges in tissue engineering.

Decellularization of tissues and organs has recently become a promising approach in tissue engineering and regenerative medicine to circumvent the challenges of organ donation and complications of transplantations. However, one main obstacle to reaching this goal is acellular vasculature angiogenesis and endothelialization. Achieving an intact and functional vascular structure as a vital pathway for supplying oxygen and nutrients remains the decisive challenge in the decellularization/re-endothelialization procedure. In order to better understand and overcome this issue, complete and appropriate knowledge of endothelialization and its determining variables is required. Decellularization methods and their effectiveness, biological and mechanical characteristics of acellular scaffolds, artificial and biological bioreactors, and their possible applications, extracellular matrix surface modification, and different types of utilized cells are factors affecting endothelialization consequences. This review focuses on the characteristics of endothelialization and how to optimize them, as well as discussing recent developments in the process of re-endothelialization.

Easy-to-Assembly System for Decellularization and Recellularization of Liver Grafts in a Bioreactor.

Decellularization of organs creates an acellular scaffold, ideal for being repopulated by cells. In this work, a low-cost perfusion system was created to be used in the process of liver decellularization and as a bioreactor after recellularization. It consists of a glass chamber to house the organ coupled to a peristaltic pump to promote liquid flow through the organ vascular tree. The rats' liver decellularization was made with a solution of sodium dodecyl sulfate. The recellularization was made with 108 mesenchymal stromal/stem cells and cultivated for seven days. The decellularized matrices showed an absence of DNA while preserving the collagen and glycosaminoglycans quantities, confirming the efficiency of the process. The functional analyses showed a rise in lactate dehydrogenase levels occurring in the first days of the cultivation, suggesting that there is cell death in this period, which stabilized on the seventh day. Histological analysis showed conservation of the collagen web and some groups of cells next to the vessels. It was possible to establish a system for decellularization and a bioreactor to use for the recellularization method. It is easy to assemble, can be ready to use in little time and be easily sterilized.

Bioactive photocrosslinkable resin solely based on refined decellularized small intestine submucosa for vat photopolymerization of in vitro tissue mimics

Three-dimensionally (3D) printed tissue mimics are unique in vitro platforms for studying human pathophysiology in a more physiologically relevant manner compared to oversimplified 2D cell cultures and complex animal models. However, their 3D printing requires an availability of materials that at the same time show a high level of biomimicry and also have a suitable viscosity profile and crosslinking kinetics for the desired printing technique. We developed a new biomimetic material for vat photopolymerization by solubilizing and functionalizing porcine small intestine submucosa (dSIS) into photocrosslinkable dSIS methacryloyl (dSIS-MA) and by subsequently formulating it into a bioactive 3D printing resin. The concentration of 1.5 wt% of dSIS-MA yielded desired viscosity and photocrosslinking kinetics, and the 3D printing of the resin resulted in fully transparent and highly swelling dSIS-MA hydrogels with a stiffness resembling native intestinal tissue. The new dSIS-MA resin was successfully 3D printed into acellular intestine-mimicking scaffolds that desirably guided the seeded human intestinal cells to grow along the 3D villi mimics. Human small intestinal organoid-derived undifferentiated primary cells grew to confluency on the dSIS-MA hydrogels and formed continuous tight junctions, thereby demonstrating the suitability of the 3D printing material for growing intestinal epithelium mimics. Furthermore, a small fraction of the human primary intestinal cells produced mucin 5AC, demonstrating early differentiation of these cells on the dSIS-MA hydrogels. The excellent cell compatibility of the dSIS-MA material combined with its high printability and biomimicry indicated that this new resin can be a great help in modelling and reproducing native tissue architectures where enhanced physiological relevancy is desired.

M2 macrophages-derived exosomes combined with acellular cartilage matrix scaffolds promote osteochondral regeneration via modulatory microenvironment

Articular cartilage (AC) regeneration has always been a difficult problem for clinicians. Anti-inflammatory (M2) macrophages have anti-inflammatory and tissue repair effects. Exosomes are reported to have multiple complicated biological functions. It has been shown that M2 macrophages-derived exosomes (M2D-Exo) can influence the course of certain diseases, but their effect on the repair of cartilage defects has not been reported. The aim of this study was to verify whether M2D-Exo could enhance the repair of acellular cartilage extracellular matrix (ACECM) scaffolds. Here, we characterized the ACECM scaffolds and identified the M2D-Exo by transmission electron microscopy (TEM), Western blotting (WB), and nanoparticle tracking analysis (NTA). In vitro, the results showed that M2D-Exo could promote the migration, proliferation and chondrogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). It was also found that M2D-Exo could reduce the expression of proinflammatory factors and promote M2 polarization, which ultimately protected chondrocytes and inhibited chondrocyte apoptosis. In vivo results confirmed that M2D-Exo could promote the repair effect of ACECM scaffolds, promote osteochondral regeneration and regulate the joint cavity inflammatory microenvironment. In conclusion, this study confirms that M2D-Exo can be used as a new therapeutic strategy for osteochondral regenerative repair.

Recellularization of Acellular Xeno Kidney Scaffold: An In Vivo Method to Generate Bioartificial Kidney.

A significant hurdle for kidney tissue engineering is reproducing the complex three-dimensional structure of the kidney. In our study, a stepwise approach of generating a reproducible Xeno kidney scaffold from a goat kidney is described, which can be implanted and recellularized by host cells. We have proposed a combination of sodium dodecyl sulfate and Triton-X-100-based protocol to generate a reproducible Xeno kidney scaffold, which was then analyzed by histology, DNA quantification, SEM, and renal angiography. Further, a small portion from the cortico-medullar region of the acellular scaffold was implanted in the rat's kidney subcapsular pocket for a period of 1 month, to check the recruitment of host cells into the scaffold. Post implantation, the extracellular matrix of the scaffold was well preserved and it did not induce any damage or inflammation in the native kidney. Implantation of the Xeno scaffold resulted in apparent early vascularization which helped in the recruitment of the host cells, which was characterized by histology, immunohistochemistry, and scanning electron microscopy. Implanted Xeno scaffold showed AQP-1, Nephrin, α-SMA, and VEGF expression in proximal tubules and renal glomerulus. Importantly, Ki-67 and WTAP-expressing cells were also observed near proximal tubules suggesting a high level of proliferation in the scaffold. Thus, showing the potential of Xeno kidney development that can be recellularized by the host cell to engineer into a functional kidney.

Combinational Treatment Involving Decellularized Extracellular Matrix Hydrogels With Mesenchymal Stem Cells Increased the Efficacy of Cell Therapy in Pancreatitis

Cell transplantation using mesenchymal stem cells (MSCs) has emerged as a promising approach to repairing and regenerating injured or impaired organs. However, the survival and retention of MSCs following transplantation remain a challenge. Therefore, we investigated the efficacy of co-transplantation of MSCs and decellularized extracellular matrix (dECM) hydrogels, which have high cytocompatibility and biocompatibility. The dECM solution was prepared by enzymatic digestion of an acellular porcine liver scaffold. It could be gelled and formed into porous fibrillar microstructures at physiological temperatures. MSCs expanded three-dimensionally in the hydrogel without cell death. Compared to the 2-dimensional cell culture, MSCs cultured in the hydrogel showed increased secretion of hepatocyte growth factor (HGF) and tumor necrosis factor-inducible gene 6 protein (TSG-6), both of which are major anti-inflammatory and anti-fibrotic paracrine factors of MSCs, under TNFα stimulation. In vivo experiments showed that the co-transplantation of MSCs with dECM hydrogel improved the survival rate of engrafted cells compared to those administered without the hydrogel. MSCs also demonstrated therapeutic effects in improving inflammation and fibrosis of pancreatic tissue in a dibutyltin dichloride (DBTC)-induced rat pancreatitis model. Combinational use of dECM hydrogel with MSCs is a new strategy to overcome the challenges of cell therapy using MSCs and can be used for treating chronic inflammatory diseases in clinical settings.

A Combination of Physical and Chemical Treatments Is More Effective in The Preparation of Acellular Uterine Scaffolds.

Decellularized uterine scaffold, as a new achievement in tissue engineering, enables recellularization and regeneration of uterine tissues and supports pregnancy in a fashion comparable to the intact uterus. The acellular methods are methods preferred in many respects due to their similarity to normal tissue, so it is necessary to try to introduce an acellularization protocol with minimum disadvantages and maximum advantages. Therefore, this study aimed to compare different protocols to achieve the optimal uterus decellularization method for future in vitro and in vivo bioengineering experiments. In this experimental study, rat uteri were decellularized by four different protocols (P) using sodium dodecyl sulfate (SDS), with different doses and time incubations (P1 and P2), SDS/Triton-X100 sequentially (P3), and a combination of physical (freeze/thaw) and chemical reagents (SDS/Triton X-100). The scaffolds were examined by histopathological staining, DNA quantification, MTT assay, blood compatibility assay, FESEM, and mechanical studies. Histology assessment showed that only in P4, cell residues were completely removed. Masson's trichrome staining demonstrated that in P3, collagen fibers were decreased; however, no damage was observed in the collagen bundles using other protocols. In indirect MTT assays, cell viabilities achieved by all used protocols were significantly higher than the native samples. The percentage of red blood cell (RBC) hemolysis in the presence of prepared scaffolds from all 4 protocols was less than 2%. The mechanical properties of none of the obtained scaffolds were significantly different from the native sample except for P3. Uteri decellularized with a combination of physical and chemical treatments (P4) was the most favorable treatment in our study with the complete removal of cell residue, preservation of the three-dimensional structure, complete removal of detergents, and preservation of the mechanical property of the scaffolds.

Retraction: Acellularized spinal cord scaffolds incorporating bpV(pic)/PLGA microspheres promote axonal regeneration and functional recovery after spinal cord injury.

[This retracts the article DOI: 10.1039/D0RA02661A.].