RESUMEN
Corneal epithelial defects and excessive wound healing might lead to severe complications. As stem cells can self-renew infinitely, they are a promising solution for regenerating the corneal epithelium and treating severe corneal epithelial injury. The chemical and biophysical properties of biological scaffolds, such as the amniotic membrane, fibrin, and hydrogels, can provide the necessary signals for stem cell proliferation and differentiation. Multiple researchers have conducted investigations on these scaffolds and evaluated them as potential therapeutic interventions for corneal disorders. These studies have identified various inherent benefits and drawbacks associated with these scaffolds. In this study, we provided a comprehensive overview of the history and use of various stem cells in corneal repair. We mainly discussed biological scaffolds that are used in stem cell transplantation and innovative materials that are under investigation.
Asunto(s)
Córnea , Lesiones de la Cornea , Trasplante de Células Madre , Ingeniería de Tejidos , Andamios del Tejido , Cicatrización de Heridas , Trasplante de Células Madre/métodos , Córnea/fisiología , Córnea/cirugía , Andamios del Tejido/efectos adversos , Andamios del Tejido/química , Lesiones de la Cornea/cirugía , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/fisiología , Humanos , AnimalesRESUMEN
Temporomandibular joint (TMJ) Meniscus removal is an option for the patient to regain full range of motion if the disc is irreversibly damaged or unable to be reduced. However, this procedure leaves the joint vulnerable to condylar remodeling and degeneration. We have shown that extracellular matrix (ECM) scaffolds remodel into a tissue with near native TMJ meniscus in previous studies. The next step towards clinical translation is to manufacture the ECM scaffold as a device under good manufacturing practices (GMP) and test it in a pre-clinical animal study under good laboratory practices (GLP). The primary objective of this study was to evaluate the in-vivo histopathological response to a Prototype GMP manufactured device made of decellularized porcine small intestinal submucosa (SIS), by observing for signs of surrounding tissue reaction to the device that are indicative of an adverse host response in comparison to an empty control at 21 days post-surgical implantation in a canine TMJ meniscus removal and implant model in a GLP setting. The conclusive findings were that the ECM device is safe for placement in the TMJ. After 21 days post implantation, histology of tissue surrounding the device and draining lymph nodes showed that the Prototype GMP device had no negative effects compared to the empty site (as evaluated by the board-certified veterinary pathologist). Furthermore, there was a lack of negative findings for clinical pathology (hematology and clinical chemistry), mortality, and body weight/weight change. Future studies will go to one year after implantation to show that the remodel device remains as a viable tissue with near native mechanical properties.
Asunto(s)
Menisco , Disco de la Articulación Temporomandibular , Animales , Perros , Matriz Extracelular/química , Intestino Delgado , Prótesis e Implantes , Porcinos , Articulación Temporomandibular , Disco de la Articulación Temporomandibular/fisiología , Disco de la Articulación Temporomandibular/cirugía , Ingeniería de Tejidos/métodos , Andamios del Tejido/efectos adversosRESUMEN
The host immune response to an implanted biomaterial, particularly the phenotype of infiltrating macrophages, is a key determinant of biocompatibility and downstream remodeling outcome. The present study used a subcutaneous rat model to compare the tissue response, including macrophage phenotype, remodeling potential, and calcification propensity of a biologic scaffold composed of glutaraldehyde-fixed bovine pericardium (GF-BP), the standard of care for heart valve replacement, with those of an electrospun polycarbonate-based supramolecular polymer scaffold (ePC-UPy), urinary bladder extracellular matrix (UBM-ECM), and a polypropylene mesh (PP). The ePC-UPy and UBM-ECM materials induced infiltration of mononuclear cells throughout the thickness of the scaffold within 2 days and neovascularization at 14 days. GF-BP and PP elicited a balance of pro-inflammatory (M1-like) and anti-inflammatory (M2-like) macrophages, while UBM-ECM and ePC-UPy supported a dominant M2-like macrophage phenotype at all timepoints. Relative to GF-BP, ePC-UPy was markedly less susceptible to calcification for the 180 day duration of the study. UBM-ECM induced an archetypical constructive remodeling response dominated by M2-like macrophages and the PP caused a typical foreign body reaction dominated by M1-like macrophages. The results of this study highlight the divergent macrophage and host remodeling response to biomaterials with distinct physical and chemical properties and suggest that the rat subcutaneous implantation model can be used to predict in vivo biocompatibility and regenerative potential for clinical application of cardiovascular biomaterials.
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Matriz Extracelular , Macrófagos , Animales , Materiales Biocompatibles/farmacología , Bovinos , Matriz Extracelular/química , Reacción a Cuerpo Extraño , Fenotipo , Ratas , Andamios del Tejido/efectos adversos , Andamios del Tejido/químicaRESUMEN
Hematopoietic stem cell (HSC) transplantation is successfully applied since the late 1950s. However, its efficacy can be impaired by insufficient numbers of donor HSCs. A promising strategy to overcome this hurdle is the use of an advanced ex vivo culture system that supports the proliferation and, at the same time, maintains the pluripotency of HSCs. Therefore, we have developed artificial 3D bone marrow-like scaffolds made of polydimethylsiloxane (PDMS) that model the natural HSC niche in vitro. These 3D PDMS scaffolds in combination with an optimized HSC culture medium allow the amplification of high numbers of undifferentiated HSCs. After 14 days in vitro cell culture, we performed transcriptome and proteome analysis. Ingenuity pathway analysis indicated that the 3D PDMS cell culture scaffolds altered PI3K/AKT/mTOR pathways and activated SREBP, HIF1α and FOXO signaling, leading to metabolic adaptations, as judged by ELISA, Western blot and metabolic flux analysis. These molecular signaling pathways can promote the expansion of HSCs and are involved in the maintenance of their pluripotency. Thus, we have shown that the 3D PDMS scaffolds activate key molecular signaling pathways to amplify the numbers of undifferentiated HSCs ex vivo effectively.
Asunto(s)
Materiales Biomiméticos/química , Dimetilpolisiloxanos/química , Células Madre Hematopoyéticas/metabolismo , Andamios del Tejido/química , Transcriptoma , Adulto , Materiales Biomiméticos/efectos adversos , Proliferación Celular , Células Cultivadas , Dimetilpolisiloxanos/efectos adversos , Femenino , Factores de Transcripción Forkhead/metabolismo , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/fisiología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Masculino , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Proteínas de Unión a los Elementos Reguladores de Esteroles/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Andamios del Tejido/efectos adversosRESUMEN
Efficient design for bone tissue engineering requires an understanding of the appropriate selection of biomimetic natural or synthetic materials and scalable fabrication technologies. In this research, poly (3-hydroxybutyrate) (PHB) and starch (5-15 wt%) as biological macromolecules were used to fabricate novel biomimetic scaffolds by electrospinning method. SEM results of electrospun scaffolds revealed bead-free nanofibers and three-dimensional homogenous structures with highly interconnected pores. Results of FTIR and Raman demonstrated that there were hydrogen bonds between the two polymers. The tensile strength of scaffolds was significantly improved by adding starch up to 10 wt%, from 3.05 to 15.54 MPa. In vitro degradation and hydrophilicity of the scaffolds were improved with the presence of starch. The viability and proliferation of MG-63 cells and alkaline phosphatase (ALP) activity were remarkably increased in the PHB-starch scaffolds compared to the PHB and control samples. The mineralization and calcium deposition of MG-63 cells were confirmed by alizarin red staining. It is concluded that PHB/starch electrospun scaffold could be a good candidate for bone tissue engineering applications.
Asunto(s)
Hidroxibutiratos/química , Almidón/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Fosfatasa Alcalina/metabolismo , Regeneración Ósea , Calcio/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Enlace de Hidrógeno , Resistencia a la Tracción , Andamios del Tejido/efectos adversosAsunto(s)
Tracto Gastrointestinal/cirugía , Neoplasias de Cabeza y Cuello/terapia , Medicina Regenerativa/métodos , Sistema Respiratorio/cirugía , Hueso Temporal/cirugía , Bioingeniería/métodos , Trasplante de Células/métodos , Disección/métodos , Femenino , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/historia , Historia del Siglo XX , Humanos , Inyecciones , Procedimientos Quírurgicos Nasales/métodos , Publicaciones Periódicas como Asunto , Fitoquímicos/administración & dosificación , Medicina Regenerativa/educación , Andamios del Tejido/efectos adversos , Apoyo a la Formación Profesional/métodosRESUMEN
Data on how the immune system reacts to decellularized scaffolds after implantation is scarce and difficult to interpret due to many heterogeneous parameters such as tissue-type match, decellularization method and treatment application. The engraftment of these scaffolds must prove safe and that they remain inert to the recipient's immune system to enable successful translational approaches and potential future clinical evaluation. Herein, we investigated the immune response after the engraftment of three decellularized scaffold types that previously showed potential to repair a uterine injury in the rat. Protocol (P) 1 and P2 were based on Triton-X100 and generated scaffolds containing 820 ng mg-1and 33 ng mg-1donor DNA per scaffold weight, respectively. Scaffolds obtained with a sodium deoxycholate-based protocol (P3) contained 160 ng donor DNA per mg tissue. The total number of infiltrating cells, and the population of CD45+leukocytes, CD4+T-cells, CD8a+cytotoxic T-cells, CD22+B-cells, NCR1+NK-cells, CD68+and CD163+macrophages were quantified on days 5, 15 and 30 after a subcutaneous allogenic (Lewis to Sprague Dawley) transplantation. Gene expression for the pro-inflammatory cytokines INF-γ, IL-1ß, IL-2, IL-6 and TNF were also examined. P1 scaffolds triggered an early immune response that may had been negative for tissue regeneration but it was stabilized after 30 d. Conversely, P3 initiated a delayed immune response that appeared negative for scaffold survival. P2 scaffolds were the least immunogenic and remained similar to autologous tissue implants. Hence, an effective decellularization protocol based on a mild detergent was advantageous from an immunological perspective and appears the most promising for futurein vivouterus bioengineering applications.
Asunto(s)
Matriz Extracelular Descelularizada , Andamios del Tejido , Trasplante Homólogo , Útero , Animales , Bioingeniería , Proliferación Celular/efectos de los fármacos , Citocinas/metabolismo , Matriz Extracelular Descelularizada/efectos adversos , Matriz Extracelular Descelularizada/química , Femenino , Inflamación/inducido químicamente , Inflamación/metabolismo , Ratas , Ratas Endogámicas Lew , Ratas Sprague-Dawley , Andamios del Tejido/efectos adversos , Andamios del Tejido/química , Trasplante Homólogo/efectos adversos , Trasplante Homólogo/métodos , Útero/citología , Útero/trasplanteRESUMEN
This study describes the development of scaffolds based on carboxyethyl chitosan (CEC) and different oxidized cashew gums (CGOx) for tissue engineering (TE) applications. After the physico-chemical characterizations of CEC and CGOx (oxidation degree of 20, 35 and 50%), these macromolecules were used for producing the CGOx-CEC hydrogels through a Schiff base reaction, in the absence of any crosslinking agent. The CGOx-CEC scaffolds obtained after a freeze-drying process were characterized for their morphology, mechanical properties, swelling ability, degradation, and porosity. Those revealed to be highly porous (25-65%), and showed a stable swelling behavior, as well as degradation properties in the absence of enzymes. The use of the cashew gum with higher degree of oxidation led to scaffolds with higher crosslinking densities and increased compressive modulus. None of the hydrogels show cytotoxicity during the 14 days of incubation. Considering all the properties mentioned, these scaffolds are excellent candidates for soft tissue regeneration, owing to the use of eco-friendly starting materials and the easy tuning of their properties.
Asunto(s)
Quitosano/análogos & derivados , Gomas de Plantas/química , Andamios del Tejido/química , Anacardium/química , Animales , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/química , Materiales Biocompatibles/toxicidad , Fenómenos Biomecánicos , Línea Celular , Quitosano/síntesis química , Quitosano/química , Fuerza Compresiva , Reactivos de Enlaces Cruzados , Hidrogeles , Ensayo de Materiales , Ratones , Microscopía Electrónica de Rastreo , Estructura Molecular , Oxidación-Reducción , Gomas de Plantas/síntesis química , Gomas de Plantas/toxicidad , Porosidad , Ingeniería de Tejidos , Andamios del Tejido/efectos adversosRESUMEN
It is well known that living cells interact mechanically with their microenvironment. Many basic cell functions, like migration, proliferation, gene expression, and differentiation, are influenced by external forces exerted on the cell. That is why it is extremely important to study how mechanical properties of the culture substrate influence the cellular molecular regulatory pathways. Optical microscopy is one of the most common experimental method used to visualize and study cellular processes. Confocal microscopy allows to observe changes in the 3D organization of the cytoskeleton in response to a precise mechanical stimulus applied with, for example, a bead trapped with optical tweezers. Optical tweezers-based method (OT) is a microrheological technique which employs a focused laser beam and polystyrene or latex beads to study mechanical properties of biological systems. Latex beads, functionalized with a specific protein, can interact with proteins located on the surface of the cellular membrane. Such interaction can significantly affect the cell's behavior. In this work, we demonstrate that beads alone, placed on the cell surface, significantly change the architecture of actin, microtubule, and intermediate filaments. We also show that the observed molecular response to such stimulus depends on the duration of the cell-bead interaction. Application of cytoskeletal drugs: cytochalasin D, jasplakinolide, and docetaxel, abrogates remodeling effects of the cytoskeleton. More important, when cells are plated on elastic substrates, which mimic the mechanical properties of physiological cellular environment, we observe formation of novel, "cup-like" structures formed by the microtubule cytoskeleton upon interaction with latex beads. These results provide new insights into the function of the microtubule cytoskeleton. Based on these results, we conclude that rigidity of the substrate significantly affects the cellular processes related to every component of the cytoskeleton, especially their architecture.
Asunto(s)
Adhesión Celular/fisiología , Citoesqueleto/metabolismo , Fibroblastos/metabolismo , Estrés Mecánico , Actinas/metabolismo , Animales , Adhesión Celular/efectos de los fármacos , Comunicación Celular/efectos de los fármacos , Comunicación Celular/fisiología , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Citoesqueleto/efectos de los fármacos , Citoesqueleto/ultraestructura , Elasticidad/fisiología , Fibroblastos/efectos de los fármacos , Fibroblastos/fisiología , Fibroblastos/ultraestructura , Dureza/fisiología , Ratones , Microscopía Confocal , Microesferas , Microtúbulos/metabolismo , Células 3T3 Swiss , Andamios del Tejido/efectos adversos , Andamios del Tejido/químicaRESUMEN
OBJECTIVE: Bioresorbable vascular scaffolds (BVSs) have been a disappointment in the evolution of drug-eluting stents used in percutaneous coronary intervention because an excessive number of thrombotic complications have been reported. The aim of this study was to evaluate long-term clinical outcomes of the Absorb BVS in patients treated using a predilation, proper sizing, and post-dilation implantation technique. METHODS: The records of 110 patients who had a total of 150 Absorb BVSs implanted were retrospectively analyzed. The rate of major adverse cardiovascular events (MACEs), defined as the composite of cardiac death, target vessel myocardial infarction (MI), and target-lesion revascularization were studied using quantitative coronary angiography. RESULTS: Of the study population, 80% were male and the mean age was 60±11.3 years. The most common diagnosis was stable angina (84%). The median length of follow-up was 53 months (range: 46-59 months). The rate of predilation and postdilation was 100%, and 95%, respectively. The 4-year rate of MACEs was 20%: cardiac death in 3 patients (2.7%), target vessel MI in 9 (8.2%), and target lesion revascularization in 20 (18.2%). Definite device thrombosis occurred in 6 of 110 patients (5.5%). One case of very late scaffold thrombosis was observed at 47 months. A small BVS diameter (2.5 mm) was found to be the most powerful independent predictor of a MACE (p=0.05). CONCLUSION: The Absorb BVS was associated with an increased risk of adverse events, including late and very late device thrombosis, despite the use of a good implementation protocol.
Asunto(s)
Implantes Absorbibles/efectos adversos , Enfermedad de la Arteria Coronaria/terapia , Intervención Coronaria Percutánea/efectos adversos , Andamios del Tejido/efectos adversos , Angiografía Coronaria/métodos , Dilatación/estadística & datos numéricos , Stents Liberadores de Fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Intervención Coronaria Percutánea/métodos , Estudios Retrospectivos , Trombosis/etiología , Factores de Tiempo , Resultado del TratamientoRESUMEN
A prosthetic scaffold development using fluorescent nanofiber is reported for an enhanced reepithelialization in wistar albino rats. In this study, a novel approach was followed to construct the biocompatible fluorescent nanofiber that will be helpful to monitor the tissue regeneration process. Here, a multifunctional carbon quantum dots (CQDs)-embedded electrospun polyacrylonitrile (PAN) nanofiber was fabricated and characterized using standard laboratory techniques. The biodegradation ability was assessed by simulated body fluid thereby analyzing porosity and water absorption capacity of the material. The fluorescent scaffold was tested for cytotoxicity and antimicrobial activity using bacterial and fibroblast cells and fluorescent stability was analyzed by bioimaging of animal and bacterial cells. Tissue regeneration capability of the developed scaffold was evaluated using wistar albino rats. Unlike biomicking scaffolds, the CQDs-embedded PAN-based substrate has given dual support by enhancing reepithelialization without growth factors and acted as an antimicrobial agent to provide contamination free tissue regeneration. Scaffolds were examined by using histostaining techniques and scanning electron microscopy to observe the reepithelialization in the regenerated tissues. The novel approach for developing infection free soft tissue regeneration was found to be phenomenal in scaffold development.
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Materiales Biocompatibles , Carbono , Regeneración Tisular Dirigida , Puntos Cuánticos/uso terapéutico , Repitelización/efectos de los fármacos , Andamios del Tejido , Resinas Acrílicas , Animales , Materiales Biocompatibles/efectos adversos , Adhesión Celular , Línea Celular , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Fibroblastos/efectos de los fármacos , Implantes Experimentales/efectos adversos , Implantes Experimentales/microbiología , Ensayo de Materiales , Ratones , Microscopía Electrónica de Rastreo , Nanofibras , Puntos Cuánticos/administración & dosificación , Ratas , Ratas Wistar , Piel/lesiones , Propiedades de Superficie , Andamios del Tejido/efectos adversos , HumectabilidadRESUMEN
As a member of the polyhydroxyalkanoate (PHAs) family, Poly(3-hydroxybutyrate) (PHB) has attracted much attention for a variety of medical applications because of its desirable properties such as high biocompatibility, nontoxic degradation products and high mechanical strength in comparison to other polymers in different fields including tissue engineering. There are different approaches such as making PHB alloy scaffolds, using PHB as a coating for ceramic-based scaffolds and producing composite scaffolds by using a mixture of PHB with ceramic particles utilized to improve hydrophobicity, degradation rate and brittleness. In this review, different applications of PHB, its alloys and composites in tissue engineering are explained based on the common methods of fabrication such as polymeric sponge replication, electrospinning and salt leaching.
Asunto(s)
Hidroxibutiratos/química , Poliésteres/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Cerámica/química , Humanos , Nanocompuestos/química , Neuronas/citología , Neuronas/efectos de los fármacos , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Prohibitinas , Piel/citología , Piel/efectos de los fármacos , Andamios del Tejido/efectos adversosRESUMEN
Poly(ethylene glycol) (PEG) hydrogels have been extensively used as scaffolds for tissue engineering applications, owing to their biocompatibility, chemical versatility, and tunable mechanical properties. However, their bio-inert properties require them to be associated with additional functional moieties to interact with cells. To circumvent this need, we propose here to reticulate PEG molecules with poly(L-lysine) dendrigrafts (DGL) to provide intrinsic cell functionalities to PEG-based hydrogels. The physico-chemical characteristics of the resulting hydrogels were studied in regard of the concentration of each component. With increasing amounts of DGL, the cross-linking time and swelling ratio could be decreased, conversely to mechanical properties, which could be tailored from 7.7 ± 0.7 to 90 ± 28.8 kPa. Furthermore, fibroblasts adhesion, viability, and morphology on hydrogels were then assessed. While cell adhesion significantly increased with the concentration of DGL, cell viability was dependant of the ratio of DGL and PEG. Cell morphology and proliferation; however, appeared mainly related to the overall hydrogel rigidity. To allow cell infiltration and cell growth in 3D, the hydrogels were rendered porous. The biocompatibility of resulting hydrogels of different compositions and porosities was evaluated by 3 week subcutaneous implantations in mice. Hydrogels allowed an extensive cellular infiltration with a mild foreign body reaction, histological evidence of hydrogel degradation, and neovascularization.
Asunto(s)
Materiales Biocompatibles/química , Polietilenglicoles/química , Polilisina/química , Andamios del Tejido , Animales , Materiales Biocompatibles/efectos adversos , Adhesión Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Reactivos de Enlaces Cruzados , Reacción a Cuerpo Extraño , Humanos , Hidrogeles , Fenómenos Mecánicos , Ratones , Neovascularización Fisiológica/efectos de los fármacos , Polietilenglicoles/efectos adversos , Polilisina/efectos adversos , Porosidad , Andamios del Tejido/efectos adversosRESUMEN
Bioengineered scaffolds composed of synthetic materials and extracellular matrix (ECM) components can offer a tissue-specific microenvironment capable of regulating cells to regenerate the structure and function of the native cartilage. Here, given the potential preservation of biomechanical and biochemical cues found in the native cartilage, particulate decellularized ECM (DC-ECM) was utilized for immobilization on the surface of nanofibrous scaffolds. Afterward, the chondro-inductive potential and ectopic cartilage formation after subcutaneous implantation of bioengineered DC-ECM scaffolds were investigated in mice model. Eight weeks post-implantation, no growth of considerable inflammatory response and neovascularization was observed in histological images of bioengineered DC-ECM scaffolds. Pre-seeded bioengineered scaffolds with human adipose-derived stem cells exhibited high levels of chondro-induction capability, indicated with immunohistochemical and gene expression results. In both interval times, we also observed chondrogenesis and tissue formation after implanting unseeded bioengineered scaffolds, which denote that the presence of DC-ECM particles can even enhance attachment and migration of the host cells and induce chondrogenesis to them. To sum up, the incorporation of DC-ECM materials to tissue engineered constructs is a promising avenue to mimic the native tissue environment for regulation of cartilage regeneration in both in vivo and in vitro settings.
Asunto(s)
Células Madre Adultas/citología , Condrogénesis/efectos de los fármacos , Matriz Extracelular Descelularizada/farmacología , Andamios del Tejido , Tejido Adiposo/citología , Adolescente , Adulto , Animales , Animales no Consanguíneos , Diferenciación Celular , Matriz Extracelular Descelularizada/toxicidad , Femenino , Reacción a Cuerpo Extraño/etiología , Humanos , Masculino , Ratones , Persona de Mediana Edad , Cartílagos Nasales , Factor de Transcripción SOX9/biosíntesis , Tejido Subcutáneo , Andamios del Tejido/efectos adversos , Adulto JovenRESUMEN
INTRODUCTION: Development of a tissue-engineered construct for hepatic regeneration remains a challenging task due to the lack of an optimum environment that support the growth of hepatocytes. Hydrogel systems possess many similarities with tissues and have the potential to provide the microenvironment essential for the cells to grow, proliferate, and remain functionally active. METHODS: In this work, fibrin (FIB) incorporated injectable alginate dialdehyde (ADA) - gelatin (G) hydrogel was explored as a matrix for liver tissue engineering. ADA was prepared by periodate oxidation of sodium alginate. An injectable formulation of ADA-G-FIB hydrogel was prepared and characterized by FTIR spectroscopy, Scanning Electron Microscopy, and Micro-Computed Tomography. HepG2 cells were cultured on the hydrogel system; cellular growth and functions were analyzed using various functional markers. RESULTS: FTIR spectra of ADA-G-FIB depicted the formation of Schiff's base at 1608.53 cm-1 with a gelation time of 3 min. ADA-G-FIB depicted a 3D surface topography with a pore size in the range of 100-200 µm. The non-cytotoxic nature of the scaffold was demonstrated using L929 cells and more than 80 % cell viability was observed. Functional analysis of cultured HepG2 cells demonstrated ICG uptake, albumin synthesis, CYP-P450 expression, and ammonia clearance. CONCLUSION: ADA-G-FIB hydrogel can be used as an effective 3D scaffold system for liver tissue engineering.
Asunto(s)
Alginatos/química , Fibrina/análogos & derivados , Hidrogeles/síntesis química , Regeneración Hepática , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Aldehídos/química , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Gelatina/química , Células Hep G2 , Humanos , Hidrogeles/efectos adversos , Ratones , Andamios del Tejido/efectos adversosRESUMEN
Amine-coated biodegradable materials based on synthetic polymers have a great potential for tissue remodeling and regeneration because of their excellent processability and bioactivity. In the present study, we have investigated the influence of various chemical compositions of amine plasma polymer (PP) coatings and the influence of the substrate morphology, represented by polystyrene culture dishes and polycaprolactone nanofibers (PCL NFs), on the behavior of vascular smooth muscle cells (VSMCs). Although all amine-PP coatings improved the initial adhesion of VSMCs, 7-day long cultivation revealed a clear preference for the coating containing about 15 at.% of nitrogen (CPA-33). The CPA-33 coating demonstrated the ideal combination of good water stability, a sufficient amine group content, and favorable surface wettability and morphology. The nanostructured morphology of amine-PP-coated PCL NFs successfully slowed the proliferation rate of VSMCs, which is essential in preventing restenosis of vascular replacements in vivo. At the same time, CPA-33-coated PCL NFs supported the continuous proliferation of VSMCs during 7-day long cultivation, with no significant increase in cytokine secretion by RAW 264.7 macrophages. The CPA-33 coating deposited on biodegradable PCL NFs therefore seems to be a promising material for manufacturing small-diameter vascular grafts, which are still lacking on the current market.
Asunto(s)
Aminas/química , Materiales Biocompatibles Revestidos/farmacología , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Nanofibras/química , Plasma/química , Polímeros/química , Aminas/efectos adversos , Aminas/inmunología , Aminas/farmacología , Animales , Adhesión Celular/efectos de los fármacos , Adhesión Celular/inmunología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Materiales Biocompatibles Revestidos/efectos adversos , Materiales Biocompatibles Revestidos/química , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Músculo Liso Vascular/citología , Músculo Liso Vascular/crecimiento & desarrollo , Miocitos del Músculo Liso/metabolismo , Nanofibras/efectos adversos , Espectroscopía de Fotoelectrones , Plasma/inmunología , Poliésteres/química , Polímeros/efectos adversos , Polímeros/farmacología , Células RAW 264.7 , Ratas , Propiedades de Superficie/efectos de los fármacos , Andamios del Tejido/efectos adversos , Andamios del Tejido/químicaRESUMEN
SUMMARY: Biologic mesh is preferred over synthetic mesh for complex and contaminated abdominal wall repairs; however, there are very little data on the risks and complications associated with its use. We report the case of a 67-year-old man with failed synthetic mesh repair for recurrent ventral hernia, who subsequently required an abdominal wall reconstruction (AWR), including the intraperitoneal sublay of noncrosslinked biologic mesh. His postoperative course was complicated with catastrophic sepsis and sustained hemodynamic instability, responding only to mesh explantation. The biologic mesh was subsequently noted to be histologically infected with invasive Candida albicans. Although noncrosslinked biologic mesh is a valuable adjunct to AWR, it is not infection-resistant. Although it is rare, infection of any foreign tissue, including biologic mesh, can occur in the setting of complex ventral abdominal wall repairs. Clinicians should be watchful for such infections in complex repairs as they may require biologic mesh explantation for clinical recovery.
Asunto(s)
Pared Abdominal/cirugía , Candida albicans/aislamiento & purificación , Candidiasis Invasiva/cirugía , Remoción de Dispositivos , Procedimientos de Cirugía Plástica/efectos adversos , Infección de la Herida Quirúrgica/cirugía , Andamios del Tejido/microbiología , Anciano , Animales , Candidiasis Invasiva/diagnóstico , Candidiasis Invasiva/microbiología , Hernia Ventral/cirugía , Herniorrafia/efectos adversos , Humanos , Masculino , Procedimientos de Cirugía Plástica/instrumentación , Recurrencia , Infección de la Herida Quirúrgica/diagnóstico , Infección de la Herida Quirúrgica/microbiología , Porcinos , Andamios del Tejido/efectos adversosRESUMEN
Poly(l-lactide-co-glycolide) (PLGA) porous scaffolds were modified with collagen type I (PLGA/coll) or hydroxyapatite (PLGA/HAp) and implanted in rabbits osteochondral defects to check their biocompatibility and bone tissue regeneration potential. The scaffolds were fabricated using solvent casting/particulate leaching method. Their total porosity was 85% and the pore size was in the range of 250-320 µm. The physico-chemical properties of the scaffolds were evaluated using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), sessile drop, and compression tests. Three types of the scaffolds (unmodified PLGA, PLGA/coll, and PLGA/HAp) were implanted into the defects created in New Zealand rabbit femoral trochlears; empty defect acted as control. Samples were extracted after 1, 4, 12, and 26 weeks from the implantation, evaluated using micro-computed tomography (µCT), and stained by Masson-Goldner and hematoxylin-eosin. The results showed that the proposed method is suitable for fabrication of highly porous PLGA scaffolds. Effective deposition of both coll and HAp was confirmed on all surfaces of the pores through the entire scaffold volume. In the in vivo model, PLGA and PLGA/HAp scaffolds enhanced tissue ingrowth as shown by histological and morphometric analyses. Bone formation was the highest for PLGA/HAp scaffolds as evidenced by µCT. Neo-tissue formation in the defect site was well correlated with degradation kinetics of the scaffold material. Interestingly, around PLGA/coll extensive inflammation and inhibited tissue healing were detected, presumably due to immunological response of the host towards collagen of bovine origin. To summarize, PLGA scaffolds modified with HAp are the most promising materials for bone tissue regeneration.
Asunto(s)
Osteocondrosis/cirugía , Poliglactina 910/química , Andamios del Tejido/química , Animales , Regeneración Ósea , Colágeno/química , Hidroxiapatitas/química , Porosidad , Conejos , Andamios del Tejido/efectos adversosRESUMEN
The effective management of tissue integration and immunological responses to transplants decisively co-determines the success of soft and hard tissue reconstruction. The aim of this in vivo study was to evaluate the eligibility of extracorporeal shock wave therapy (ESWT) with respect to its ability to modulate angiogenesis and immune response to a collagen matrix (CM) for tissue engineering in the chorioallantoic membrane (CAM) assay, which is performed with fertilized chicken eggs. CM were placed on the CAM on embryonic development day (EDD) 7; at EDD-10, ESWT was conducted at 0.12 mJ/mm2 with 500 impulses each. One and four days later, angiogenesis represented by vascularized area, vessel density, and vessel junctions as well as HIF-1α and VEGF gene expression were evaluated. Furthermore, immune response (iNOS2, MMP-9, and MMP-13 via qPCR) was assessed and compared between ESWT- and non-ESWT-groups. At EDD-14, the vascularized area (+115% vs. +26%) and the increase in vessel junctions (+751% vs. +363%) were significantly higher in the ESWT-group. ESWT significantly increased MMP-9 gene expression at EDD-11 and significantly decreased MMP-13 gene expression at EDD-14 as compared to the controls. Using the CAM assay, an enhanced angiogenesis and neovascularization in CM after ESWT were observed. Furthermore, ESWT could reduce the inflammatory activity after a latency of four days.