scholarly journals Characterization and cytocompatibility of 3D porous biomimetic scaffold derived from rabbit nucleus pulposus tissue in vitro

2021 ◽  
Vol 32 (1) ◽  
Author(s):  
Yu Zhang ◽  
Wei Tan ◽  
Mingxin Wu ◽  
Jin Sun ◽  
Wei Cao ◽  
...  
Keyword(s):  
Nucleus Pulposus ◽  
Porous Scaffold ◽  
Experimental Treatment ◽  
Mechanical Tests ◽  
Control Group ◽  
Porous Scaffolds ◽  
High Porosity ◽  
Marrow Mesenchymal Stem Cells ◽  
Biomimetic Scaffold

Abstract Intervertebral disc (IVD) degeneration is one of the most important causes of lower back pain. Tissue engineering provides a new method for the experimental treatment of degenerative disc diseases. This study aims to develop a natural, acellular, 3D interconnected porous scaffold derived from the extracellular matrix (ECM) of nucleus pulposus. The nucleus pulposus (NP) was decellularized by sequential detergent-nuclease methods, including physical crushing, freeze-drying and cross-linking. These 3D porous scaffolds were fabricated with a high porosity of (81.28 ± 4.10)%, an ideal pore size with appropriate mechanical properties. Rabbit bone marrow mesenchymal stem cells (rBMSCs) were seeded and cultured on the scaffolds. And the mechanical tests showed the compressive elastic modulus of the scaffolds cultured for 4 weeks reached 0.12 MPa, which was better than that of the scaffolds cultured for 2 weeks (0.07 MPa) and that of the control group (0.04 MPa). Scanning electron microscopy (SEM), histological assays, molecular biology assays revealed that the scaffolds could provide an appropriate microstructure and environment for the adhesion, proliferation, migration and secretion of seeded cells in vitro. As assays like histology, immunohistochemistry and the real-time qRT-PCR showed, NP-like tissues were preliminarily formed. In conclusion, the 3D porous scaffold derived from NP ECM is a potential biomaterial for the regeneration of NP tissues.

scholarly journals Porous Geometry Guided Micro-mechanical Environment Within Scaffolds for Cell Mechanobiology Study in Bone Tissue Engineering

2021 ◽  
Vol 9 ◽  
Author(s):  
Feihu Zhao ◽  
Yi Xiong ◽  
Keita Ito ◽  
Bert van Rietbergen ◽  
Sandra Hofmann
Keyword(s):  
Porous Scaffold ◽  
Mechanical Strain ◽  
Three Dimensional ◽  
Pore Geometry ◽  
Cell Physiology ◽  
Porous Scaffolds ◽  
Mechanical Environment ◽  
Functional Features ◽  
Future Work

Mechanobiology research is for understanding the role of mechanics in cell physiology and pathology. It will have implications for studying bone physiology and pathology and to guide the strategy for regenerating both the structural and functional features of bone. Mechanobiological studies in vitro apply a dynamic micro-mechanical environment to cells via bioreactors. Porous scaffolds are commonly used for housing the cells in a three-dimensional (3D) culturing environment. Such scaffolds usually have different pore geometries (e.g. with different pore shapes, pore dimensions and porosities). These pore geometries can affect the internal micro-mechanical environment that the cells experience when loaded in the bioreactor. Therefore, to adjust the applied micro-mechanical environment on cells, researchers can tune either the applied load and/or the design of the scaffold pore geometries. This review will provide information on how the micro-mechanical environment (e.g. fluid-induced wall shear stress and mechanical strain) is affected by various scaffold pore geometries within different bioreactors. It shall allow researchers to estimate/quantify the micro-mechanical environment according to the already known pore geometry information, or to find a suitable pore geometry according to the desirable micro-mechanical environment to be applied. Finally, as future work, artificial intelligent – assisted techniques, which can achieve an automatic design of solid porous scaffold geometry for tuning/optimising the micro-mechanical environment are suggested.

scholarly journals FSTL1 aggravates OVA-induced allergic airway inflammation by activating NLRP3 inflammasome

2020 ◽  
Author(s):  
Yan Wang ◽  
Tian Liu ◽  
Jun-fei Wang ◽  
Bao-yi Liu ◽  
Jin-xiang Wu ◽  
...  
Keyword(s):  
Airway Inflammation ◽  
Nlrp3 Inflammasome ◽  
Allergic Airway Inflammation ◽  
Experimental Treatment ◽  
Underlying Mechanism ◽  
Whole Body ◽  
Control Group ◽  
Asthmatic Patients

Abstract Background Asthma is a common respiratory disease characterized by chronic airway inflammation. As a novel inflammatory mediator, follistatin-like protein 1 (FSTL1) can activate immune reaction, suggesting that it may contribute to inflammatory disorders such as asthma. Besides, there are growing evidences that nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) / Interleukin (IL)-1β axis participates in asthma. In this study, we investigated the role of FSTL1 in allergic airway inflammation and its underlying mechanism of activating NLRP3 inflammasome. Methods Circulating FSTL1 and IL-1β levels were quantified in serum of asthmatic patients and controls. Whole-body ablation Fstl1 heterozygous mice (Fstl1 +/- ) and control group were assessed after the experimental treatment. The effects of FSTL1 on NLRP3 inflammasome were also tested in primary macrophages of mice in vitro. Results The concentration of FSTL1 and IL-1β in serum of asthmatic patients were elevated compared with controls and were positively correlated. FSTL1 deficiency ameliorated infiltration of inflammatory cells,corresponding pathological changes,cytokine responses (IL-1β, IL-5,IL-13), mucous hypersecretion and hyper-responsiveness of airway after Ovalbumin (OVA) exposure in the mouse model. Additionally, inhibition of NLRP3 with MCC950 attenuated FSTL1-induced activation of NLRP3 inflammasome and airway inflammation in vivo and vitro. Conclusions Our data showed that FSTL1 played an important role in allergic airway inflammation by activating NLRP3 inflammasome, providing the possibility that FSTL1 could be applied as a therapeutic strategy on asthma.

Development of HA-PLGA Scaffold Encapsulating Intact BMP-2 Using Solid Freeform Fabrication Technology

2011 ◽  
Author(s):  
Jin-Hyung Shim ◽  
Jong Young Kim ◽  
Kyung Shin Kang ◽  
Jung Kyu Park ◽  
Sei Kwang Hahn ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Bone Regeneration ◽  
Porous Scaffold ◽  
Solid Freeform Fabrication ◽  
Three Dimensional ◽  
Porous Scaffolds ◽  
Prolonged Release ◽  
Cellular Activity ◽  
Freeform Fabrication

Tissue engineering is an interdisciplinary field that focuses on restoring and repairing tissues or organs. Cells, scaffolds, and biomolecules are recognized as three main components of tissue engineering. Solid freeform fabrication (SFF) technology is required to fabricate three-dimensional (3D) porous scaffolds to provide a 3D environment for cellular activity. SFF technology is especially advantageous for achieving a fully interconnected, porous scaffold. Bone morphogenic protein-2 (BMP-2), an important biomolecule, is widely used in bone tissue engineering to enhance bone regeneration activity. However, methods for the direct incorporation of intact BMP-2 within 3D scaffolds are rare. In this work, 3D porous scaffolds with poly(lactic-co-glycolic acid) chemically grafted hyaluronic acid (HA-PLGA), in which intact BMP-2 was directly encapsulated, were successfully fabricated using SFF technology. BMP-2 was previously protected by poly(ethylene glycol) (PEG), and the BMP-2/PEG complex was incorporated in HA-PLGA using an organic solvent. The HAPLGA/PEG/BMP-2 mixture was dissolved in chloroform and deposited via a multi-head deposition system (MHDS), one type of SFF technology, to fabricate a scaffold for tissue engineering. An additional air blower system and suction were installed in the MHDS for the solvent-based fabrication method. An in vitro evaluation of BMP-2 release was conducted, and prolonged release of intact BMP-2, for up to 28 days, was confirmed. After confirmation of advanced proliferation of pre osteoblasts, a superior differentiation effect of the HA-PLGA/PEG/BMP-2 scaffold was validated by measuring high expression levels of bone-specific markers, such as alkaline phosphatase (ALP) and osteocalcin (OC). We show that our solvent-based fabrication is a non-toxic method for restoring cellular activity. Moreover, the HAPLGA/PEG/BMP-2 scaffold was effective for bone regeneration.

37 Healthy Foals Produced Using Bone Marrow-Mesenchymal Stem Cells as Nuclear Donors in Horse Cloning

2018 ◽  
Vol 30 (1) ◽  
pp. 158
Author(s):  
R. Olivera ◽  
L. Moro ◽  
R. Jordan ◽  
C. Luzzani ◽  
S. Miriuka ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Mesenchymal Stem Cells ◽  
Umbilical Cord ◽  
Donor Cell ◽  
Control Group ◽  
Nuclear Reprogramming ◽  
Marrow Mesenchymal Stem Cells

Somatic cell nuclear transfer efficiency is based on the capacity of the donor cell to be reset and reprogrammed to an embryonic state. So, the less differentiated the donor cells are, the more easily they could be reprogrammed by a recipient cytoplasm. Failures on appropriate nuclear reprogramming frequently lead to abnormalities associated with the placenta, umbilical cord, birthweight, and limbs. In the present study, we evaluated the efficiency of bone marrow mesenchymal stem cells (BM-MSC) compared with adult fibroblasts (AF) as nuclear donors in horse cloning and evaluated both in vitro and in vivo development of the embryos generated. Moreover, we focused on comparing the health of the foals generated and on the presence of anatomical abnormalities in foals produced from the different treatments. Embryos produced by AI, recovered by uterine flushing, and transferred to recipient mares were used as controls. All variables were analysed by Fisher test (P < 0.05). The cloning procedure was performed according to Olivera et al. (2016 PLoS One 11, e0164049, 10.1371/journal.pone.0164049). Both cleavage and blastocyst rates were higher when MSC were used as nuclear donors (P < 0.05). Cleavage rates were 85.6% (3875/4527) v. 90.2% (3095/3432) and blastocyst rates were 10.9% (492/4527) and 18.1% (622/3432) for AF and MSC groups, respectively. In the AF group, 476 blastocysts were transferred to recipient mares (232 transfers), and in the MSC group, 594 blastocysts were transferred 297 transfers). In the AI control group, 88 embryos were transferred. Pregnancies were diagnosed by transrectal ultrasonography 15 days after embryo transfer in all the groups. Pregnancy rates were similar between both cloning groups (41/232, 17.7% and 37/297, 12.5%for AF and MSC, respectively), but higher in the AI group (71/88, 80.7%). However, significant differences were observed in the birth of viable offsprings among the cloning groups. Despite similar rates of foal delivery (AF, 17/41, 41.5%; MSC, 21/37, 56.7%), a higher proportion of viable foals were obtained from the MSC group (20/37, 54.1%) compared with the AF group (9/41, 22%; P < 0.05). Surprisingly, as in the AI group (63/63, 100%), all of the viable foals obtained using MSC (20/20, 100%) were considered normal and did not show abnormalities associated with cloning. In contrast, in the AF group, only 4/9 (44.4%) were considered normal foals. The defects present in the other 5 foals were related to flexural and angular limb deformities and umbilical cord malformations. These were corrected rapidly with standard treatments or, in the case of the umbilical cords, minor surgery. This study shows for the first time that BM-MSC can be used as nuclear donors in horse cloning and that the foals obtained are as healthy as those produced by AI, showing no abnormalities related to deficiencies in nuclear reprogramming.

Fabrication and evaluation of a warp knitted polypropylene/polylactic acid composite mesh for pelvic floor repair

2017 ◽  
Vol 88 (10) ◽  
pp. 1099-1111 ◽  
Author(s):  
Yao Lu ◽  
Pei-hua Zhang
Keyword(s):  
Polylactic Acid ◽  
Tissue Growth ◽  
Control Group ◽  
Growth Speed ◽  
High Porosity ◽  
Composite Mesh ◽  
Factors Affecting ◽  
Knitted Structure

Surgical mesh for repairing pelvic defects is expected to be stiff to improve surgical convenience, as well as be soft and flexible to relieve foreign body sensation. This paper aims to develop a new composite mesh (PA) consisted of polypropylene (PP) monofilaments and polylactic acid (PLA) monofilaments according to this expectation. The PA mesh was designed by the two-bar warp knitting technique to have a knitted structure with light weight (19.9 g/m2) and high porosity (porosity). A commercial lightweight PP mesh—Surgimesh® Prolapse mesh—was used as the control group. The mechanical property, in vitro degradation, and in vivo biocompatibility were then measured. The results revealed that the addition of stiffer, stronger PLA monofilaments did not significantly strengthen PA mesh, but made the mesh stiff. The warp knitted structure, porosity and pore size are vital factors affecting mesh mechanical properties. PLA monofilaments in PA mesh were degraded in 74 weeks, with a maximum weight loss reaching 62.4%. PA mesh was demonstrated to have better biocompatibility with evidences of lower shrinkage (13.1%) and faster tissue growth speed.

scholarly journals Effects of Concentrated Growth Factor on the Proliferation, Migration, and Osteogenic Differentiation of Rat Bone Marrow Mesenchymal Stem Cells: An in vitro study

2020 ◽  
Author(s):  
Xiang Yu ◽  
Hui Ren ◽  
Qi Shang ◽  
Gengyang Shen ◽  
Kai Tang ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Osteogenic Differentiation ◽  
Control Group ◽  
Elisa Assay ◽  
Alizarin Red ◽  
Expression Levels ◽  
Marrow Mesenchymal Stem Cells ◽  
Mrna Expression Levels

Abstract Background Concentrated growth factor (CGF) has been reported to be effective in bone formation or soft/hard tissue healing in recent years. Despite a few studies regarding the effects of CGF on the proliferation, migration, and osteogenic differentiation of BMSCs, their underlying mechanisms are not fully understood. The purpose of this study is to investigate the effects and possible mechanisms of CGF on the proliferation, migration, and osteogenic differentiation of rat-derived bone marrow mesenchymal stem cells (BMSCs) in vitro. Methods CGF was extracted from the Sprague Dawley (SD) rats by venipuncture of the abdominal aortic vein, and scanning electron microscopy (SEM) was used for the structural characterization. The release of bone morphogenetic protein 2 (BMP-2) from CGF was measured over the periods of 1 ~ 14 days, using the enzyme-linked immunosorbent (Elisa) assay. Cell Counting Kit-8 (CCK-8) assay was used to measure cell proliferation. Migration capacity was analyzed using the transwell assay. The osteogenic differentiation and mineralization ability were determined by Alkaline phosphatase activity (ALP) staining and Alizarin Red staining respectively. Quantitative real-time PCR (RT-qPCR), was used to evaluate the mRNA expression levels of Runx2, Ocn, Smad1, and Smad5 after culture for 14 days. Further, the protein expression of BMP-2, phosphorylated-Smad1/5 (p-Smad1/5), and Smad1/5/8 was determined by Western blot after a 14-day cell culture. Results The SEM analysis showed a porous and dense three-dimensional fibrin network in CGF. The Elisa assay showed that BMP-2 was released from CGF extract for more than 14d, and it reached a peak at the time point of 5d. The cell densities of the CGF group at the different concentrations (5%, 10%, and 20%) were significantly higher than that of the control group at the periods of day 1 to day 5 (p < 0.05). Moreover, the number of migratory cells of the CGF group was greater than that of the control group at 24 h. ALP activity analysis and Alizarin Red staining results demonstrated that CGF may successfully induce osteogenic differentiation of BMSCs. Moreover, the RT-qPCR results showed that CGF extracts dramatically enhanced the mRNA expression levels of Runx2, Ocn, Smad1, and Smad5 in BMSCs at days 14 (p < 0.05). Furthermore, Western blot results showed that CGF extracts markedly up-regulated the protein expression levels of BMP-2, p-Smad1/5, and Smad1/5/8. Conclusions CGF can promote the proliferation, migration, and promote the osteogenic differentiation potential of BMSCs in vitro. The BMP-2/Smad signaling pathway was involved in the osteogenic differentiation and mineralization of BMSCs induced by CGF. Therefore, CGF has good application potential in tissue engineering for bone regeneration and repair.

scholarly journals Characterization and in vitro assessment of three-dimensional extrusion Mg-Sr codoped SiO2-complexed porous microhydroxyapatite whisker scaffolds for biomedical engineering

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Chengyong Li ◽  
Tingting Yan ◽  
Zhenkai Lou ◽  
Zhimin Jiang ◽  
Zhi Shi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Cell Proliferation ◽  
Pore Size ◽  
Osteogenic Differentiation ◽  
Bone Repair ◽  
Porous Scaffold ◽  
Porous Scaffolds ◽  
Sprague Dawley ◽  
Active Elements

Abstract Background Large bone defects have always been a great challenge for orthopedic surgeons. The use of a good bone substitute obtained by bone tissue engineering (BTE) may be an effective treatment method. Artificial hydroxyapatite, a commonly used bone defect filler, is the main inorganic component of bones. Because of its high brittleness, fragility, and lack of osteogenic active elements, its application is limited. Therefore, its fragility should be reduced, its osteogenic activity should be improved, and a more suitable scaffold should be constructed. Methods In this study, a microhydroxyapatite whisker (mHAw) was developed, which was doped with the essential trace active elements Mg2+ and Sr2+ through a low-temperature sintering technique. After being formulated into a slurry, a bionic porous scaffold was manufactured by extrusion molding and freeze drying, and then SiO2 was used to improve the mechanical properties of the scaffold. The hydrophilicity, pore size, surface morphology, surface roughness, mechanical properties, and release rate of the osteogenic elements of the prepared scaffold were detected and analyzed. In in vitro experiments, Sprague–Dawley (SD) rat bone marrow mesenchymal stem cells (rBMSCs) were cultured on the scaffold to evaluate cytotoxicity, cell proliferation, spreading, and osteogenic differentiation. Results Four types of scaffolds were obtained: mHAw-SiO2 (SHA), Mg-doped mHAw-SiO2 (SMHA), Sr-doped mHAw-SiO2 (SSHA), and Mg-Sr codoped mHAw-SiO2 (SMSHA). SHA was the most hydrophilic (WCA 5°), while SMHA was the least (WCA 8°); SMHA had the smallest pore size (247.40 ± 23.66 μm), while SSHA had the largest (286.20 ± 19.04 μm); SHA had the smallest Young's modulus (122.43 ± 28.79 MPa), while SSHA had the largest (188.44 ± 47.89 MPa); and SHA had the smallest compressive strength (1.72 ± 0.29 MPa), while SMHA had the largest (2.47 ± 0.25 MPa). The osteogenic active elements Si, Mg, and Sr were evenly distributed and could be sustainably released from the scaffolds. None of the scaffolds had cytotoxicity. SMSHA had the highest supporting cell proliferation and spreading rate, and its ability to promote osteogenic differentiation of rBMSCs was also the strongest. Conclusions These composite porous scaffolds not only have acceptable physical and chemical properties suitable for BTE but also have higher osteogenic bioactivity and can possibly serve as potential bone repair materials.

A Finite Element Prediction of Strain on Cells in a Highly Porous Collagen-Glycosaminoglycan Scaffold

2008 ◽  
Vol 130 (6) ◽  
Author(s):  
A. J. F. Stops ◽  
L. A. McMahon ◽  
D. O’Mahoney ◽  
P. J. Prendergast ◽  
P. E. McHugh
Keyword(s):  
Tissue Engineering ◽  
Finite Element ◽  
Load Transfer ◽  
Porous Scaffold ◽  
Computational Prediction ◽  
Element Model ◽  
Porous Scaffolds ◽  
Wide Range ◽  
A Cell

Tissue engineering often involves seeding cells into porous scaffolds and subjecting the scaffold to mechanical stimulation. Current experimental techniques have provided a plethora of data regarding cell responses within scaffolds, but the quantitative understanding of the load transfer process within a cell-seeded scaffold is still relatively unknown. The objective of this work was to develop a finite element representation of the transient and heterogeneous nature of a cell-seeded collagen-GAG-scaffold. By undertaking experimental investigation, characteristics such as scaffold architecture and shrinkage, cellular attachment patterns, and cellular dimensions were used to create a finite element model of a cell-seeded porous scaffold. The results demonstrate that a very wide range of microscopic strains act at the cellular level when a sample value of macroscopic (apparent) strain is applied to the collagen-GAG-scaffold. An external uniaxial strain of 10% generated a cellular strain as high as 49%, although the majority experienced less than ∼5% strain. The finding that the strain on some cells could be higher than the macroscopic strain was unexpected and proves contrary to previous in vitro investigations. These findings indicate a complex system of biophysical stimuli created within the scaffolds and the difficulty of inducing the desired cellular responses from artificial environments. Future in vitro studies could also corroborate the results from this computational prediction to further explore mechanoregulatory mechanisms in tissue engineering.

scholarly journals Three dimensional porous scaffolds derived from collagen, elastin and fibrin proteins orchestrate adipose tissue regeneration

2021 ◽  
Vol 12 ◽  
pp. 204173142110192
Author(s):  
Prasad Sawadkar ◽  
Nandin Mandakhbayar ◽  
Kapil D Patel ◽  
Jennifer Olmas Buitrago ◽  
Tae Hyun Kim ◽  
...  
Keyword(s):  
Stem Cells ◽  
Soft Tissue ◽  
Porous Scaffold ◽  
Pathological Condition ◽  
Donor Site ◽  
Porous Scaffolds ◽  
Adipose Derived Stem Cells ◽  
Natural Polymers

Current gold standard to treat soft tissue injuries caused by trauma and pathological condition are autografts and off the shelf fillers, but they have inherent weaknesses like donor site morbidity, immuno-compatibility and graft failure. To overcome these limitations, tissue-engineered polymers are seeded with stem cells to improve the potential to restore tissue function. However, their interaction with native tissue is poorly understood so far. To study these interactions and improve outcomes, we have fabricated scaffolds from natural polymers (collagen, fibrin and elastin) by custom-designed processes and their material properties such as surface morphology, swelling, wettability and chemical cross-linking ability were characterised. By using 3D scaffolds, we comprehensive assessed survival, proliferation and phenotype of adipose-derived stem cells in vitro. In vivo, scaffolds were seeded with adipose-derived stem cells and implanted in a rodent model, with X-ray microtomography, histology and immunohistochemistry as read-outs. Collagen-based materials showed higher cell adhesion and proliferation in vitro as well as higher adipogenic properties in vivo. In contrast, fibrin demonstrated poor cellular and adipogenesis properties but higher angiogenesis. Elastin formed the most porous scaffold, with cells displaying a non-aggregated morphology in vitro while in vivo elastin was the most degraded scaffold. These findings of how polymers present in the natural polymers mimicking ECM and seeded with stem cells affect adipogenesis in vitro and in vivo can open avenues to design 3D grafts for soft tissue repair.

Sign in / Sign up

Export Citation Format

Share Document