Methods: The genes were transferred into chondrocytes at passage-1 (P1) via lipofection. The post-transfected chondrocytes (SOX9-, TERT- and SOX9/TERT) were analysed at P1, P2 and P3. The non-transfected group was used as control. The 3D culture was established using the chondrocytes seeded in a disc-shaped PLGA/fibrin and PLGA scaffolds. The resulting 3D "cells-scaffolds" constructs were analysed at week-1, -2 and -3. The histoarchitecture was evaluated using haematoxylin and eosin, alcian blue and safranin o stains. The quantitative sulphated glycosaminoglycan (sGAG) content was measured using biochemical assay. The cartilage-specific markers expression were analysed via real-time polymerase chain reaction.
Results: All monolayer cultured chondrocytes showed flattened, fibroblast-like appearance throughout passages. Proteoglycan and sGAG were not detected at the pericellular matrix region of the chondrocytes. The sGAG content assay indicated the matrix production depletion in the culture. The cartilage-specific markers, COL2A1 and ACAN, were downregulated. However, the dedifferentiation marker, COL1A1 was upregulated. In 3D "cells-scaffolds" constructs, regardless of transfection groups, chondrocytes seeded in PLGA/fibrin showed a more uniform distribution and produced denser matrix than the PLGA group especially at week-3. Both sGAG and proteoglycan were clearly visualised in the constructs, supported by the increment of sGAG content, quantitatively. Both COL2A1 and ACAN were upregulated in SOX9/TERT-PLGA and SOX9/TERT-PLGA/fibrin respectively. While, COL1A1 was downregulated in SOX9/TERT-PLGA.
Conclusion: These findings indicated that the SOX9/TERT-transfected chondrocytes incorporation into 3D scaffolds facilitates the cartilage regeneration which is viable structurally and functionally.
METHODS: Full-thickness surgical ablation of the medial-tibial cartilage was performed in New Zealand white (NZW) rabbits. Control rabbits (Group-I) received no treatment; Animals in other groups were treated as follows. Group-II: BM-MSCs (1 × 106 cells) + HyalofastTM; Group-III: BMMSCs (1 × 106 cells) + cartilage pellet (CP); and Group-IV: BM-MSCs (1 × 106 cells) + HyalofastTM + CP. Animals were sacrificed at 12 weeks and cartilage regeneration analyzed using histopathology, International Cartilage Repair Society (ICRS-II) score, magnetic resonance observation of cartilage repair tissue (MOCART) score and biomechanical studies.
RESULTS: Gross images showed good tissue repair (Groups IV > III > Group II) and histology demonstrated intact superficial layer, normal chondrocyte arrangement, tidemark and cartilage matrix staining (Groups III and IV) compared to the untreated control (Group I) respectively. ICRS-II score was 52.5, 65.0, 66 and 75% (Groups I-IV) and the MOCART score was 50.0, 73.75 and 76.25 (Groups II-IV) respectively. Biomechanical properties of the regenerated cartilage tissue in Group IV closed resembled that of a normal cartilage.
CONCLUSION: HyalofastTM together with BM-MSCs and CP led to efficient cartilage regeneration following full thickness surgical ablation of tibial articular cartilage in vivo in rabbits. Presence of hyaluronic acid in the scaffold and native microenvironment cues probably facilitated differentiation and integration of BM-MSCs.
Electronic Supplementary Material: Supplementary material is available for this article at 10.1007/s13770-016-9093-2 and is accessible for authorized users.
METHODs: Data collection was based on the key articles published in English language in years between 2006 and 2018 using the searching terms of urethral stricture and tissue engineering on PubMed database.
RESULTS: Differentiation of mesenchymal stem cells into urothelial and smooth muscle cells to be used for urologic application does not offer any advantage over autologous urothelial and smooth muscle cells. Among studied scaffolds, synthetic scaffolds with proper porosity and mechanical strength is the best option to be used for urethral tissue engineering.
CONCLUSION: Hypoxia-preconditioned mesenchymal stem cells in combination with autologous cells seeded on a pre-vascularized synthetic and biodegradable scaffold can be said to be the best combinatory strategy in engineering of human urethra.
METHODS: Nerve conduit was developed using decellularised artery seeded with C. asiatica-neurodifferentiated MSCs (ndMSCs). A 1.5 cm sciatic nerve injury in Sprague-Dawley rat was bridged with reversed autograft (RA) (n = 3, the gold standard treatment), MSC-seeded conduit (MC) (n = 4) or ndMSC-seeded conduit (NC) (n = 4). Pinch test and nerve conduction study were performed every 2 weeks for a total of 12 weeks. At the 12th week, the conduits were examined by histology and transmission electron microscopy.
RESULTS: NC implantation improved the rats' sensory sensitivity in a similar manner to RA. At the 12th week, nerve conduction velocity was the highest in NC compared with that of RA and MC. Axonal regeneration was enhanced in NC and RA as shown by the expression of myelin basic protein (MBP). The average number of myelinated axons was significantly higher in NC than in MC but significantly lower than in RA. The myelin sheath thickness was higher in NC than in MC but lower than in RA.
CONCLUSION: NC showed promising effects on nerve regeneration and functional restoration similar to those of RA. These findings revealed the neuroregenerative properties of C. asiatica and its potential as an alternative strategy for the treatment of critical size nerve defect.
METHODS: Human adipose-derived stem cells isolated from fat tissues were differentiated into smooth muscle cells and then seeded onto a triple-layered PLGA sheet to form a bladder construct. Adult athymic rats underwent subtotal urinary bladder resection and were divided into three treatment groups (n = 3): Group 1 ("sham") underwent anastomosis of the remaining basal region, Group 2 underwent reconstruction with the cell-free scaffold, and Group 3 underwent reconstruction with the tissue-engineered bladder construct. Animals were monitored on a daily basis and euthanisation was performed whenever a decline in animal health was detected.
RESULTS: All animals in Groups 1, 2 and 3 survived for at least 7 days and were followed up to a maximum of 12 weeks post-operation. It was found that by Day 14, substantial ingrowth of smooth muscle and urothelial cells had occurred in Group 2 and 3. In the long-term follow up of group 3 (tissue-engineered bladder construct group), it was found that the urinary bladder wall was completely regenerated and bladder function was fully restored. Urodynamic and radiological evaluations of the reconstructed bladder showed a return to normal bladder volume and function.Histological analysis revealed the presence of three muscular layers and a urothelium similar to that of a normal bladder. Immunohistochemical staining using human-specific myocyte markers (myosin heavy chain and smoothelin) confirmed the incorporation of the seeded cells in the newly regenerated muscular layers.
CONCLUSION: Implantation of PLGA construct seeded with smooth muscle cells derived from human adipose stem cells can lead to regeneration of the muscular layers and urothelial ingrowth, leading to formation of a completely functional urinary bladder.
METHODS: This animal protocol has been approved by Universiti Kebangsaan Malaysia Animal Ethical Committee. The TEHB scaffold prepared from hydroxyapatite using gel casting method. A total of six adolescent female sheep were chosen for this study. Later, all the sheep were euthanized in a proper manner and the bone harvested for biomechanical study. Bone marrow was collected from iliac crest of the sheep and bone marrow stem cells (BMSCs) isolated and cultured. BMSCs then cultured in osteogenic medium for osteoprogenitor cells development and the plasma collected was seeded with osteoprogenitor cells mixed with calcium chloride. Bone defect of 3 cm length of tibia bone created from each sheep leg and implanted with autologous and TEHB scaffold in 2 different groups of sheep. Wound site was monitored weekly until the wound completely healed and conventional X-ray performed at week 1 and 24. Shear test was conducted to determine the shear force on the autologous bone and TEHB scaffold after implantation for 24 weeks.
RESULTS: All of the sheep survived without any complications during the study period and radiograph showed new bone formation. Later, the bone harvested was for biomechanical study. The highest shear force for the autologous group was 13 MPa and the lowest was 5 MPa while for the scaffold group, the highest was 10 MPa and the lowest was 3 MPa. Although, proximal and distal interface of autologous bone graft shows higher shear strength compared to the TEHB scaffold but there is no significant difference in both groups, p value > 0.05. Histologically in both proximal and distal interface in both arms shows bone healing and woven bone formation.
CONCLUSION: TEHB scaffold impregnated with osteoprogenitor cells has the potential to be developed as a bone substitute in view of its strength and capability to promote bone regeneration.
METHODS: Skeletal human muscle cells were cultured in four different conditions; control, EGF, laminin (Lam) and laminin EGF (Lam + EGF). Using live imaging system, their cellular properties; attachment, migration and growth were exposed to Rho kinase inhibitor, Y-27632, and EGF-receptor (EGF-R) inhibitor, gefitinib were measured.
RESULTS: Myoblast migration and proliferation was enhanced significantly by synergistic stimulation of laminin and EGF (0.61 ± 0.14 µm/min, 0.008 ± 0.001 h-1) compare to that by EGF alone (0.26 ± 0.13 µm/min, 0.004 ± 0.0009 h-1). However, no changes in proliferation and migration were observed for fibroblasts among the culture conditions. Inhibition of Rho kinase resulted in the increase of the myoblast migration on the laminin-coated surface with EGF condition (0.64 ± 0.18 µm/min). Compared to the untreated conditions, myoblasts cultured on the laminin-coated surface and EGF demonstrated elongated morphology, and average cell length increase significantly. In contrast, inhibition of EGF-R resulted in the decrease of myoblast migration on the laminin coated surface with EGF supplemented condition (0.43 ± 0.05 µm/min) in comparison to the untreated control (0.53 ± 0.05 µm/min).
CONCLUSION: Laminin and EGF preferentially enhance the proliferation and migration of myoblasts, and Rho kinase and EGF-R play a role in this synergistic effect. These results will be beneficial for the propagation of skeletal muscle cells for clinical applications.
METHODS: Three groups of Sprague Dawley rats were used: intervention, vehicle group and negative control groups (n = 6 in each). Intravenous injection of 60 mg/kg sodium iodate (day 0) induced retinal degeneration. On day 4 post-injection of sodium iodate, the rats in the intervention group received intravenous DPSC and subretinal DPSC in the right eye; rats in the vehicle group received subretinal Hank's balance salt solution and intravenous normal saline; while negative control group received nothing. Electroretinogram (ERG) was performed to assess the retinal function at day 0 (baseline), day 4, day 11, day 18, day 26, and day 32. By the end of the study at day 32, the rats were euthanized, and both their enucleated eyes were sent for histology.
RESULTS: No significant difference in maximal ERG a-wave (p = 0.107) and b-wave, (p = 0.153) amplitude was seen amongst the experimental groups. However, photopic 30 Hz flicker amplitude of the study eye showed significant differences in the 3 groups (p = 0.032). Within the intervention group, there was an improvement in 30 Hz flicker ERG response of all 6 treated right eyes, which was injected with subretinal DPSC; while the 30 Hz flicker ERG of the non-treated left eyes remained flat. Histology showed improved outer nuclear layer thickness in intervention group; however, findings were not significant compared to the negative and vehicle groups.
CONCLUSION: Combination of subretinal and intravenous injection of DPSCs may have potential to rescue cone function from a NaIO3-induced retinal injury model.
METHODS: In this review, we first discussed the anatomy, physiology and pathophysiology of tendon and ligament injuries and its current treatment. Secondly, we explored the current role of tendon and ligament tissue engineering, describing its recent advances. After that, we also described stem cell and cell secreted product approaches in tendon and ligament injuries. Lastly, we examined the role of the bioreactor and mechanical loading in in vitro maturation of engineered tendon and ligament.
RESULTS: Tissue engineering offers various alternative ways of treatment from biological tissue constructs to stem cell therapy and cell secreted products. Bioreactor with mechanical stimulation is instrumental in preparing mature engineered tendon and ligament substitutes in vitro.
CONCLUSIONS: Tissue engineering showed great promise in replacing the damaged tendon and ligament. However, more study is needed to develop ideal engineered tendon and ligament.
METHODS: Electronic databases including PubMed, Google Scholar and Cochrane were searched for years 2004-2017. The keywords used were leukaemia, allogenic stem cell transplantation, prevalence, side effects, long term, delayed, adverse effects, complications and outcome.
RESULTS: A total of ten articles were included for analysis. There were 5 prospective studies, 3 retrospective studies and 2 cross sectional studies. A total of 40,069 patients, (20,189 males and 17,191 females) participated in these 10 studies. The gender of 2689 patients were not disclosed. Most common late complications and prevalence were chronic graft versus host disease (43% at 5 years post HSCT), secondary tumor (21% at 20 years post HSCT), hypothyroidism (11% at 15 years), bronchiolitis obliterans (9.7% at 122 days), cardiovascular disease (7.5% at 15 years) and avascular necrosis (5.4% at 10 years). The prevalence of azoospermia was 71.1% and depression, 18%. For the latter two conditions no time limit was available. Follow up duration ranged from 2 years till 30 years post HSCT.
CONCLUSION: While allogenic stem cell transplantation is an effective cure for leukaemia, the procedure is associated with complications that can have their onset many years after the procedure.
METHODS: The effective dose of Ecklonia cava phlorotannins (ECP) for hyperglycaemic wound healing was determined prior to phlorotannin nanofibre fabrication using polyvinyl-alcohol (PVA), polyvinylpyrrolidone (PVP), and ECP. Vapour glutaraldehyde was used for crosslinking of the PVA/PVP nanofibres. The phlorotannin nanofibres were characterised, and their safety and cytocompatibility were validated. Next, the wound healing effect of phlorotannin nanofibres was determined with 2D wound scratch assay, whereas immunofluorescence staining of Collagen-I (Col-I) and Cytokeratin-14 (CK-14) was performed in human dermal fibroblasts (HDF) and human epidermal keratinocytes (HEK), respectively.
RESULTS: Our results demonstrated that 0.01 μg/mL ECP significantly improved hyperglycaemic wound healing without compromising cell viability and proliferation. Among all nanofibres, PVA/PVP/0.01 wt% ECP nanofibres exhibited the best hyperglycaemic wound healing effect. They displayed a diameter of 334.7 ± 10.1 nm, a porosity of 40.7 ± 3.3%, and a WVTR of 1718.1 ± 32.3 g/m2/day. Besides, the FTIR spectra and phlorotannin release profile validated the successful vapour glutaraldehyde crosslinking and ECP incorporation. We also demonstrated the potential of phlorotannin nanofibres as a non-cytotoxic wound dressing as they support the viability and proliferation of both HDF and HEK. Furthermore, phlorotannin nanofibres significantly ameliorated the impaired hyperglycaemic wound healing and restored the hyperglycaemic-induced Col-I reduction in HDF.
CONCLUSION: Taken together, our findings show that phlorotannin nanofibres have the potential to be used as a diabetic wound dressing.
METHODS: MEDLINE/PubMed and Google scholar databases were used for the selection of literature. The keywords used were mesenchymal stem cells, extracellular vesicles, clinical application of EVs and challenges EVs production.
RESULTS: These EVs have demonstrated robust capabilities in transporting intracellular cargo, playing a critical role in facilitating cell-to-cell communication by carrying functional molecules, including proteins, RNA species, DNAs, and lipids. Utilizing EVs as an alternative to stem cells offers several benefits, such as improved safety, reduced immunogenicity, and the ability to traverse biological barriers. Consequently, EVs have emerged as an increasingly attractive option for clinical use.
CONCLUSION: From this perspective, this review delves into the advantages and challenges associated with employing MSC-EVs in clinical settings, with a specific focus on their potential in treating conditions like lung diseases, cancer, and autoimmune disorders.