Displaying publications 21 - 40 of 97 in total

Abstract:
Sort:
  1. Fulltext Synergistic Effect of Laminin and Epidermal Growth Factor on Biological and Morphological Properties of Co-Cultured Myoblasts and Fibroblasts
    Mat Afandi MA, Maarof M, Chowdhury SR, Bt Hj Idrus R
    Tissue Eng Regen Med, 2020 12;17(6):835-845.
    PMID: 32767029 DOI: 10.1007/s13770-020-00283-3
    BACKGROUND: One of the long-standing problems of myoblasts in vitro expansion is slow cell migration and this causes fibroblast population to exceed myoblasts. In this study, we investigated the synergistic effect of laminin and epidermal growth factor (EGF) on co-cultured myoblasts and fibroblasts for cell attachment, proliferation and migration.

    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.

  2. Ovine tendon collagen: Extraction, characterisation and fabrication of thin films for tissue engineering applications
    Fauzi MB, Lokanathan Y, Aminuddin BS, Ruszymah BHI, Chowdhury SR
    Mater Sci Eng C Mater Biol Appl, 2016 Nov 01;68:163-171.
    PMID: 27524008 DOI: 10.1016/j.msec.2016.05.109
    Collagen is the most abundant extracellular matrix (ECM) protein in the human body, thus widely used in tissue engineering and subsequent clinical applications. This study aimed to extract collagen from ovine (Ovis aries) Achilles tendon (OTC), and to evaluate its physicochemical properties and its potential to fabricate thin film with collagen fibrils in a random or aligned orientation. Acid-solubilized protein was extracted from ovine Achilles tendon using 0.35M acetic acid, and 80% of extracted protein was measured as collagen. SDS-PAGE and mass spectrometry analysis revealed the presence of alpha 1 and alpha 2 chain of collagen type I (col I). Further analysis with Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) confirms the presence of triple helix structure of col I, similar to commercially available rat tail col I. Drying the OTC solution at 37°C resulted in formation of a thin film with randomly orientated collagen fibrils (random collagen film; RCF). Introduction of unidirectional mechanical intervention using a platform rocker prior to drying facilitated the fabrication of a film with aligned orientation of collagen fibril (aligned collagen film; ACF). It was shown that both RCF and ACF significantly enhanced human dermal fibroblast (HDF) attachment and proliferation than that on plastic surface. Moreover, cells were distributed randomly on RCF, but aligned with the direction of mechanical intervention on ACF. In conclusion, ovine tendon could be an alternative source of col I to fabricate scaffold for tissue engineering applications.
  3. Human Amniotic Membrane with Aligned Electrospun Fiber as Scaffold for Aligned Tissue Regeneration
    Hasmad H, Yusof MR, Mohd Razi ZR, Hj Idrus RB, Chowdhury SR
    Tissue Eng Part C Methods, 2018 06;24(6):368-378.
    PMID: 29690856 DOI: 10.1089/ten.TEC.2017.0447
    Fabrication of composite scaffolds is one of the strategies proposed to enhance the functionality of tissue-engineered scaffolds for improved tissue regeneration. By combining multiple elements together, unique biomimetic scaffolds with desirable physical and mechanical properties can be tailored for tissue-specific applications. Despite having a highly porous structure, the utility of electrospun fibers (EF) as scaffold is usually hampered by their insufficient mechanical strength. In this study, we attempted to produce a mechanically competent scaffold with cell-guiding ability by fabricating aligned poly lactic-co-glycolic acid (PLGA) fibers on decellularized human amniotic membrane (HAM), known to possess favorable tensile and wound healing properties. Decellularization of HAM in 18.75 μg/mL of thermolysin followed by a brief treatment in 0.25 M sodium hydroxide efficiently removed the amniotic epithelium and preserved the ultrastructure of the underlying extracellular matrix. The electrospinning of 20% (w/v) PLGA 50:50 polymer on HAM yielded beadless fibers with straight morphology. Subsequent physical characterization revealed that EF-HAM scaffold with a 3-min fabrication had the most aligned fibers with the lowest fiber diameter in comparison with EF-HAM 5- and 7-min scaffolds. Hydrated EF-HAM scaffolds with 3-min deposition had a greater tensile strength than the other scaffolds despite having thinner fibers. Nevertheless, wet HAM and EF-HAMs regardless of the fiber thicknesses had a significantly lower Young's modulus, and hence, a higher elasticity compared with dry HAM and EF-HAMs. Biocompatibility analysis showed that the viability and migration rate of skeletal muscle cells on EF-HAMs were similar to control and HAM alone. Skeletal muscle cells seeded on HAM were shown to display random orientation, whereas cells on EF-HAM scaffolds were oriented along the alignment of the electrospun PLGA fibers. In summary, besides having good mechanical strength and elasticity, EF-HAM scaffold design decorated with aligned fiber topography holds a promising potential for use in the development of aligned tissue constructs.
  4. Development of an In Vitro Cardiac Ischemic Model Using Primary Human Cardiomyocytes
    Hafez P, Chowdhury SR, Jose S, Law JX, Ruszymah BHI, Mohd Ramzisham AR, et al.
    Cardiovasc Eng Technol, 2018 09;9(3):529-538.
    PMID: 29948837 DOI: 10.1007/s13239-018-0368-8
    Developing experimental models to study ischemic heart disease is necessary for understanding of biological mechanisms to improve the therapeutic approaches for restoring cardiomyocytes function following injury. The aim of this study was to develop an in vitro hypoxic/re-oxygenation model of ischemia using primary human cardiomyocytes (HCM) and define subsequent cytotoxic effects. HCM were cultured in serum and glucose free medium in hypoxic condition with 1% O2 ranging from 30 min to 12 h. The optimal hypoxic exposure time was determined using Hypoxia Inducible Factor 1α (HIF-1α) as the hypoxic marker. Subsequently, the cells were moved to normoxic condition for 3, 6 and 9 h to replicate the re-oxygenation phase. Optimal period of hypoxic/re-oxygenation was determined based on 50% mitochondrial injury via 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide assay and cytotoxicity via lactate dehydrogenase (LDH) assay. It was found that the number of cells expressing HIF-1α increased with hypoxic time and 3 h was sufficient to stimulate the expression of this marker in all the cells. Upon re-oxygenation, mitochondrial activity reduced significantly whereas the cytotoxicity increased significantly with time. Six hours of re-oxygenation was optimal to induce reversible cell injury. The injury became irreversible after 9 h as indicated by > 60% LDH leakage compared to the control group cultured in normal condition. Under optimized hypoxic reoxygenation experimental conditions, mesenchymal stem cells formed nanotube with ischemic HCM and facilitated transfer of mitochondria suggesting the feasibility of using this as a model system to study molecular mechanisms of myocardial injury and rescue.
  5. Rapid treatment of full-thickness skin loss using ovine tendon collagen type I scaffold with skin cells
    Mh Busra F, Rajab NF, Tabata Y, Saim AB, B H Idrus R, Chowdhury SR
    J Tissue Eng Regen Med, 2019 05;13(5):874-891.
    PMID: 30811090 DOI: 10.1002/term.2842
    The full-thickness skin wound is a common skin complication affecting millions of people worldwide. Delayed treatment of this condition causes the loss of skin function and integrity that could lead to the development of chronic wounds or even death. This study was aimed to develop a rapid wound treatment modality using ovine tendon collagen type I (OTC-I) bio-scaffold with or without noncultured skin cells. Genipin (GNP) and carbodiimide (EDC) were used to cross-link OTC-I scaffold to improve the mechanical strength of the bio-scaffold. The physicochemical, biomechanical, biodegradation, biocompatibility, and immunogenicity properties of OTC-I scaffolds were investigated. The efficacy of this treatment approach was evaluated in an in vivo skin wound model. The results demonstrated that GNP cross-linked OTC-I scaffold (OTC-I_GNP) had better physicochemical and mechanical properties compared with EDC cross-linked OTC-I scaffold (OTC-I_EDC) and noncross-link OTC-I scaffold (OTC-I_NC). OTC-I_GNP and OTC-I_NC demonstrated no toxic effect on cells as it promoted higher cell attachment and proliferation of both primary human epidermal keratinocytes and human dermal fibroblasts compared with OTC-I_EDC. Both OTC-I_GNP and OTC-I_NC exhibited spontaneous formation of bilayer structure in vitro. Immunogenic evaluation of OTC-I scaffolds, in vitro and in vivo, revealed no sign of immune response. Finally, implantation of OTC-I_NC and OTC-I_GNP scaffolds with noncultured skin cells demonstrated enhanced healing with superior skin maturity and microstructure features, resembling native skin in contrast to other treatment (without noncultured skin cells) and control group. The findings of this study, therefore, suggested that both OTC-I scaffolds with noncultured skin cells could be promising for the rapid treatment of full-thickness skin wound.
  6. Fulltext Current Progress in Tendon and Ligament Tissue Engineering
    Lim WL, Liau LL, Ng MH, Chowdhury SR, Law JX
    Tissue Eng Regen Med, 2019 Dec;16(6):549-571.
    PMID: 31824819 DOI: 10.1007/s13770-019-00196-w
    BACKGROUND: Tendon and ligament injuries accounted for 30% of all musculoskeletal consultations with 4 million new incidences worldwide each year and thus imposed a significant burden to the society and the economy. Damaged tendon and ligament can severely affect the normal body movement and might lead to many complications if not treated promptly and adequately. Current conventional treatment through surgical repair and tissue graft are ineffective with a high rate of recurrence.

    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.

  7. Fulltext Attachment, Proliferation, and Morphological Properties of Human Dermal Fibroblasts on Ovine Tendon Collagen Scaffolds: A Comparative Study
    Busra FM, Lokanathan Y, Nadzir MM, Saim A, Idrus RBH, Chowdhury SR
    Malays J Med Sci, 2017 Mar;24(2):33-43.
    PMID: 28894402 DOI: 10.21315/mjms2017.24.2.5
    INTRODUCTION: Collagen type I is widely used as a biomaterial for tissue-engineered substitutes. This study aimed to fabricate different three-dimensional (3D) scaffolds using ovine tendon collagen type I (OTC-I), and compare the attachment, proliferation and morphological features of human dermal fibroblasts (HDF) on the scaffolds.

    METHODS: This study was conducted between the years 2014 to 2016 at the Tissue Engineering Centre, UKM Medical Centre. OTC-I was extracted from ovine tendon, and fabricated into 3D scaffolds in the form of sponge, hydrogel and film. A polystyrene surface coated with OTC-I was used as the 2D culture condition. Genipin was used to crosslink the OTC-I. A non-coated polystyrene surface was used as a control. The mechanical strength of OTC-I scaffolds was evaluated. Attachment, proliferation and morphological features of HDF were assessed and compared between conditions.

    RESULTS: The mechanical strength of OTC-I sponge was significantly higher than that of the other scaffolds. OTC-I scaffolds and the coated surface significantly enhanced HDF attachment and proliferation compared to the control, but no differences were observed between the scaffolds and coated surface. In contrast, the morphological features of HDF including spreading, filopodia, lamellipodia and actin cytoskeletal formation differed between conditions.

    CONCLUSION: OTC-I can be moulded into various scaffolds that are biocompatible and thus could be suitable as scaffolds for developing tissue substitutes for clinical applications and in vitro tissue models. However, further study is required to determine the effect of morphological properties on the functional and molecular properties of HDF.

  8. One-Step Purification of Human Skeletal Muscle Myoblasts and Subsequent Expansion Using Laminin-Coated Surface
    Chowdhury SR, binti Ismail A, Chee SC, bin Laupa MS, binti Jaffri F, Saberi SE, et al.
    Tissue Eng Part C Methods, 2015 Nov;21(11):1135-42.
    PMID: 26061720 DOI: 10.1089/ten.TEC.2015.0015
    Skeletal myoblasts have been extensively used to study muscle growth and differentiation, and were recently tested for their application as cell therapy and as a gene delivery system to treat muscle and nonmuscle diseases. However, contamination of fibroblasts in isolated cells from skeletal muscle is one of the long-standing problems for routine expansion. This study aimed to establish a simple one-step process to purify myoblasts and maintain their purity during expansion. Mixed cells were preplated serially on laminin- and collagen type I-coated surfaces in a different array for 5, 10, and 15 min. Immunocytochemical staining with antibodies specific to myoblasts was performed to evaluate myoblast attachment efficiency, purity, and yield. It was found that laminin-coated surface favors the attachment of myoblasts. Highest myoblast purity of 78.9% ± 6.8% was achieved by 5 min of preplating only on the laminin-coated surface with a yield of 56.9% ± 3.3%. Primary cells, isolated from skeletal muscle (n = 4), confirm the enhancement of purity through preplating on laminin-coated surface for 5 min. Subsequent expansion after preplating enhanced myoblast purity due to an increase in myoblast growth than fibroblasts. Myoblast purity of ∼ 98% was achieved when another preplating was performed during passaging. In conclusion, myoblasts can be purified and efficiently expanded in one step by preplating on laminin-coated surface, which is a simple and robust technique.
  9. Large-Scale Expansion of Human Mesenchymal Stem Cells
    Hassan MNFB, Yazid MD, Yunus MHM, Chowdhury SR, Lokanathan Y, Idrus RBH, et al.
    Stem Cells Int, 2020;2020:9529465.
    PMID: 32733574 DOI: 10.1155/2020/9529465
    Mesenchymal stem cells (MSCs) are multipotent stem cells with strong immunosuppressive property that renders them an attractive source of cells for cell therapy. MSCs have been studied in multiple clinical trials to treat liver diseases, peripheral nerve damage, graft-versus-host disease, autoimmune diseases, diabetes mellitus, and cardiovascular damage. Millions to hundred millions of MSCs are required per patient depending on the disease, route of administration, frequency of administration, and patient body weight. Multiple large-scale cell expansion strategies have been described in the literature to fetch the cell quantity required for the therapy. In this review, bioprocessing strategies for large-scale expansion of MSCs were systematically reviewed and discussed. The literature search in Medline and Scopus databases identified 26 articles that met the inclusion criteria and were included in this review. These articles described the large-scale expansion of 7 different sources of MSCs using 4 different bioprocessing strategies, i.e., bioreactor, spinner flask, roller bottle, and multilayered flask. The bioreactor, spinner flask, and multilayered flask were more commonly used to upscale the MSCs compared to the roller bottle. Generally, a higher expansion ratio was achieved with the bioreactor and multilayered flask. Importantly, regardless of the bioprocessing strategies, the expanded MSCs were able to maintain its phenotype and potency. In summary, the bioreactor, spinner flask, roller bottle, and multilayered flask can be used for large-scale expansion of MSCs without compromising the cell quality.
  10. Collagen Type I: A Versatile Biomaterial
    Chowdhury SR, Mh Busra MF, Lokanathan Y, Ng MH, Law JX, Cletus UC, et al.
    Adv Exp Med Biol, 2018 10 26;1077:389-414.
    PMID: 30357700 DOI: 10.1007/978-981-13-0947-2_21
    Collagen type I is the most abundant matrix protein in the human body and is highly demanded in tissue engineering, regenerative medicine, and pharmaceutical applications. To meet the uprising demand in biomedical applications, collagen type I has been isolated from mammalians (bovine, porcine, goat and rat) and non-mammalians (fish, amphibian, and sea plant) source using various extraction techniques. Recent advancement enables fabrication of collagen scaffolds in multiple forms such as film, sponge, and hydrogel, with or without other biomaterials. The scaffolds are extensively used to develop tissue substitutes in regenerating or repairing diseased or damaged tissues. The 3D scaffolds are also used to develop in vitro model and as a vehicle for delivering drugs or active compounds.
  11. Fulltext 3D Culture of MSCs on a Gelatin Microsphere in a Dynamic Culture System Enhances Chondrogenesis
    Sulaiman S, Chowdhury SR, Fauzi MB, Rani RA, Yahaya NHM, Tabata Y, et al.
    Int J Mol Sci, 2020 Apr 13;21(8).
    PMID: 32294921 DOI: 10.3390/ijms21082688
    Recent advancement in cartilage tissue engineering has explored the potential of 3D culture to mimic the in vivo environment of human cartilaginous tissue. Three-dimensional culture using microspheres was described to play a role in driving the differentiation of mesenchymal stem cells to chondrocyte lineage. However, factors such as mechanical agitation on cell chondrogenesis during culture on the microspheres has yet to be elucidated. In this study, we compared the 2D and 3D culture of bone-marrow-derived mesenchymal stem cells (BMSCs) on gelatin microspheres (GMs) in terms of MSC stemness properties, immune-phenotype, multilineage differentiation properties, and proliferation rate. Then, to study the effect of mechanical agitation on chondrogenic differentiation in 3D culture, we cultured BMSCs on GM (BMSCs-GM) in either static or dynamic bioreactor system with two different mediums, i.e., F12: DMEM (1:1) + 10% FBS (FD) and chondrogenic induction medium (CIM). Our results show that BMSCs attached to the GM surface and remained viable in 3D culture. BMSCs-GM proliferated faster and displayed higher stemness properties than BMSCs on a tissue culture plate (BMSCs-TCP). GMs also enhanced the efficiency of in-vitro chondrogenesis of BMSCs, especially in a dynamic culture with higher cell proliferation, RNA expression, and protein expression compared to that in a static culture. To conclude, our results indicate that the 3D culture of BMSCs on gelatin microsphere was superior to 2D culture on a standard tissue culture plate. Furthermore, culturing BMSCs on GM in dynamic culture conditions enhanced their chondrogenic differentiation.
  12. Comparison of three different skin substitutes in promoting wound healing in an ovine model
    Subramaniam T, Shaiful Hadi N, Sulaiman S, Fauzi MB, Hj Idrus RB, Chowdhury SR, et al.
    Burns, 2021 Aug 20.
    PMID: 34893370 DOI: 10.1016/j.burns.2021.08.012
    Skin substitutes are designed dressings intended to promote wound closure. In previous in vitro and in vivo studies on small animal, an acellular skin patch made of collagen hydrogel with dermal fibroblast conditioned medium (Col-DFCM), a collagen sponge scaffold with freshly harvested skin cells (OTC), and a platelet-rich-plasma gel with freshly harvested skin cells (PRP) have been developed and tested for immediate treatment of full-thickness wound. However, to determine the safety and efficacy of these skin patches for clinical applications, further study in a large animal model is needed. The aim of this study is to evaluate the potential of Col-DFCM, OTC and PRP in treating full-thickness wound in an ovine model via histological analysis and immunohistochemistry staining were performed, with the untreated (NT) group serving as the control. Gross examination was conducted on day 7, 14 and 21 to determine the wound closure rate. The findings of percentage of wound size reduction showed that the wound healed fastest in the presence of Col-DFCM (91.34 ± 23.35%) followed by OTC (84.49 ± 23.13%), PRP (77.73 ± 20.9%) and NT group (73.94 ± 23.71%). Histological evaluation with Hematoxylin & Eosin (H & E) and Masson's trichrome staining was used to study the structure of the wound area. The results showed that OTC treated wound was more mature as indicated by the presence of a thinner epidermis followed by the Col-DFCM, PRP and NT group. Immunohistochemistry analysis also confirmed the integrity and maturity of the regenerated skin, with positive expression of cytokeratin 10 (CK10) and involucrin in the epidermal layer. In conclusion, Col-DFCM, OTC and PRP treatments promote healing of full-thickness wound and have the potential to be used clinically for rapid treatment of full-thickness wound.
  13. Fibroblast-derived matrices-based human skin equivalent as an in vitro psoriatic model for drug testing
    Yap WH, Cheah TY, Yong LC, Chowdhury SR, Ng MH, Kwan Z, et al.
    J Biosci, 2021;46.
    PMID: 34475316
    Psoriasis is a chronic skin disease characterized by thickening and disorganization of the skin's protective barrier. Although current models replicate some aspects of the disease, development of therapeutic strategies have been hindered by absence of more relevant models. This study aimed to develop and characterize an in vitro psoriatic human skin equivalent (HSE) using human keratinocytes HaCat cell line grown on fibroblasts-derived matrices (FDM). The constructed HSEs were treated with cytokines (IL-1α, TNF-α, IL-6, and IL22) to allow controlled induction of psoriasis-associated features. Histological stainings showed that FDMHSE composed of a fully differentiated epidermis and fibroblast-populated dermis comparable to native skin and rat tail collagen-HSE. Hyperproliferation (CK16 and Ki67) and inflammatory markers (TNF-α and IL-6) expression were significantly enhanced in the cytokine-induced FDM- and rat tail collagen HSEs compared to non-treated HSE counterparts. The characteristics were in line with those observed in psoriasis punch biopsies. Treatment with all-trans retinoic acid (ATRA) has shown to suppress these effects, where HSE models treated with both ATRA and cytokines exhibit histological characteristics, hyperproliferation and differentiation markers expression like non-treated control HSEs. Cytokine-induced FDM-HSE, constructed entirely from human cell lines, provides an excellent opportunity for psoriasis research and testing new therapeutics.
  14. Fulltext Effect of Different Collection Times of Dermal Fibroblast Conditioned Medium (DFCM) on In Vitro Re-Epithelialisation Process
    Abdul Ghani N', Razali RA, Chowdhury SR, Fauzi MB, Bin Saim A, Ruszymah BHI, et al.
    Biomedicines, 2022 Dec 09;10(12).
    PMID: 36551960 DOI: 10.3390/biomedicines10123203
    A key event in wound healing is re-epithelialisation, which is mainly regulated via paracrine signalling of cytokines, chemokines, and growth factors secreted by fibroblasts. Fibroblast-secreted factors can be collected from the used culture medium, known as dermal fibroblast conditioned medium (DFCM). The goal of this study was to optimise the culture condition to acquire DFCM and evaluate its effect on keratinocyte attachment, proliferation, migration, and differentiation. Confluent fibroblasts were cultured with serum-free keratinocyte-specific (DFCM-KM) and fibroblast-specific (DFCM-FM) medium at different incubation times (Days 1, 2, and 3). DFCM collected after 3 days of incubation (DFCM-KM-3 and DFCM-FM-3) contained a higher protein concentration compared to other days. Supplementation of DFCM-KM-3 enhanced keratinocyte attachment, while DFCM-FM-3 significantly increased the keratinocyte wound-healing rate, with an increment of keratinocyte area and collective cell migration, which was distinctly different from DFCM-KM-3 or control medium. Further analysis confirmed that the presence of calcium at higher concentrations in DFCM-FM facilitated the changes. The confluent dermal fibroblasts after 3 days of incubation with serum-free culture medium produced higher proteins in DFCM, resulting in enhanced in vitro re-epithelialisation. These results suggest that the delivery of DFCM could be a potential treatment strategy for wound healing.
  15. The effects of human serum to the morphology, proliferation and gene expression level of the respiratory epithelium in vitro
    Yunus MH, Siang KC, Hashim NI, Zhi NP, Zamani NF, Sabri PP, et al.
    Tissue Cell, 2014 Aug;46(4):233-40.
    PMID: 24973262 DOI: 10.1016/j.tice.2014.05.003
    The culture of human airway epithelial cells has played an important role in advancing our understanding of the metabolic and molecular mechanisms underlying normal function and disease pathology of airway epithelial cells. The present study focused on investigating the effects of human serum (HS) on the qualitative and quantitative properties of the human respiratory epithelium compared to the fetal bovine serum (FBS), as a supplement in culture. Respiratory epithelial (RE) cells derived from human nasal turbinate were co-cultured with fibroblasts, subsequently separated at 80-90% confluency by differential trypsinization. RE cells were then sub-cultured into 2 different plates containing 5% allogenic HS and FBS supplemented media respectively up to passage 1 (P1). Cell morphology, growth rate, cell viability and population doubling time were assessed under light microscope, and levels of gene expression were measured via real time reverse transcriptase-polymerase chain reaction (qRT-PCR). RE cells appeared as polygonal shape and expanded when cultured in HS whereas RE cells in FBS were observed to be easily matured thus limit the RE cells expansion. Proliferation rate of RE cells in HS supplemented media (7673.18 ± 1207.15) was 3 times higher compared to RE in FBS supplemented media (2357.68 ± 186.85). Furthermore, RE cells cultured in HS-supplemented media required fewer days (9.15 ± 1.10) to double in numbers compared to cells cultured in FBS-supplemented media (13.66 ± 0.81). Both the differences were significant (p<0.05). However, there were no significant differences in the viability of RE cells in both groups (p=0.105). qRT-PCR showed comparable expressions of gene Cytokeratin-14 (CK-14), Cytokeratin-18 (CK-18) and Mucin-5 subtype B (MUC5B) in RE cells cultured in both groups (p>0.05). In conclusion, HS is a comparatively better choice of media supplement in accelerating growth kinetics of RE cells in vitro thus producing a better quality of respiratory epithelium for future tracheal reconstruction.
  16. Cytotoxic evaluation of biomechanically improved crosslinked ovine collagen on human dermal fibroblasts
    Awang MA, Firdaus MA, Busra MB, Chowdhury SR, Fadilah NR, Wan Hamirul WK, et al.
    Biomed Mater Eng, 2014;24(4):1715-24.
    PMID: 24948455 DOI: 10.3233/BME-140983
    Earlier studies in our laboratory demonstrated that collagen extracted from ovine tendon is biocompatible towards human dermal fibroblast. To be able to use this collagen as a scaffold in skin tissue engineering, a mechanically stronger scaffold is required that can withstand manipulation before transplantation. This study was conducted to improve the mechanical strength of this collagen sponge using chemical crosslinkers, and evaluate their effect on physical, chemical and biocompatible properties. Collagen sponge was crosslinked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and glutaraldehyde (GA). Tensile test, FTIR study and mercury porosimetry were used to evaluate mechanical properties, chemical property and porosity, respectively. MTT assay was performed to evaluate the cytotoxic effect of crosslinked collagen sponge on human dermal fibroblasts. The FTIR study confirmed the successful crosslinking of collagen sponge. Crosslinking with EDC and GA significantly increased the mechanical strength of collagen sponge, with GA being more superior. Crosslinking of collagen sponge significantly reduced the porosity and the effect was predominant in GA-crosslinked collagen sponge. The GA-crosslinked collagen showed significantly lower, 60% cell viability towards human dermal fibroblasts compared to that of EDC-crosslinked collagen, 80% and non-crosslinked collagen, 100%. Although the mechanical strength was better when using GA but the more toxic effect on dermal fibroblast makes EDC a more suitable crosslinker for future skin tissue engineering.
  17. Fulltext Safety and Efficacy of Human Wharton's Jelly-Derived Mesenchymal Stem Cells Therapy for Retinal Degeneration
    Leow SN, Luu CD, Hairul Nizam MH, Mok PL, Ruhaslizan R, Wong HS, et al.
    PLoS One, 2015;10(6):e0128973.
    PMID: 26107378 DOI: 10.1371/journal.pone.0128973
    To investigate the safety and efficacy of subretinal injection of human Wharton's Jelly-derived mesenchymal stem cells (hWJ-MSCs) on retinal structure and function in Royal College of Surgeons (RCS) rats.
  18. Fulltext Type II Collagen-Conjugated Mesenchymal Stem Cells Micromass for Articular Tissue Targeting
    Sulaiman SB, Chowdhury SR, Busra MFBM, Abdul Rani RB, Mohamad Yahaya NHB, Tabata Y, et al.
    Biomedicines, 2021 Jul 23;9(8).
    PMID: 34440084 DOI: 10.3390/biomedicines9080880
    The tissue engineering approach in osteoarthritic cell therapy often requires the delivery of a substantially high cell number due to the low engraftment efficiency as a result of low affinity binding of implanted cells to the targeted tissue. A modification towards the cell membrane that provides specific epitope for antibody binding to a target tissue may be a plausible solution to increase engraftment. In this study, we intercalated palmitated protein G (PPG) with mesenchymal stem cells (MSCs) and antibody, and evaluated their effects on the properties of MSCs either in monolayer state or in a 3D culture state (gelatin microsphere, GM). Bone marrow MSCs were intercalated with PPG (PPG-MSCs), followed by coating with type II collagen antibody (PPG-MSC-Ab). The effect of PPG and antibody conjugation on the MSC proliferation and multilineage differentiation capabilities both in monolayer and GM cultures was evaluated. PPG did not affect MSC proliferation and differentiation either in monolayer or 3D culture. The PPG-MSCs were successfully conjugated with the type II collagen antibody. Both PPG-MSCs with and without antibody conjugation did not alter MSC proliferation, stemness, and the collagen, aggrecan, and sGAG expression profiles. Assessment of the osteochondral defect explant revealed that the PPG-MSC-Ab micromass was able to attach within 48 h onto the osteochondral surface. Antibody-conjugated MSCs in GM culture is a potential method for targeted delivery of MSCs in future therapy of cartilage defects and osteoarthritis.
  19. Fulltext Micro-Computed Tomography Detection of Gold Nanoparticle-Labelled Mesenchymal Stem Cells in the Rat Subretinal Layer
    Mok PL, Leow SN, Koh AE, Mohd Nizam HH, Ding SL, Luu C, et al.
    Int J Mol Sci, 2017 Feb 08;18(2).
    PMID: 28208719 DOI: 10.3390/ijms18020345
    Mesenchymal stem cells are widely used in many pre-clinical and clinical settings. Despite advances in molecular technology; the migration and homing activities of these cells in in vivo systems are not well understood. Labelling mesenchymal stem cells with gold nanoparticles has no cytotoxic effect and may offer suitable indications for stem cell tracking. Here, we report a simple protocol to label mesenchymal stem cells using 80 nm gold nanoparticles. Once the cells and particles were incubated together for 24 h, the labelled products were injected into the rat subretinal layer. Micro-computed tomography was then conducted on the 15th and 30th day post-injection to track the movement of these cells, as visualized by an area of hyperdensity from the coronal section images of the rat head. In addition, we confirmed the cellular uptake of the gold nanoparticles by the mesenchymal stem cells using transmission electron microscopy. As opposed to other methods, the current protocol provides a simple, less labour-intensive and more efficient labelling mechanism for real-time cell tracking. Finally, we discuss the potential manipulations of gold nanoparticles in stem cells for cell replacement and cancer therapy in ocular disorders or diseases.
  20. Fulltext Search for supersymmetry in events with a photon, jets, b -jets, and missing transverse momentum in proton-proton collisions at 13 Te
    Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.
    Eur Phys J C Part Fields, 2019;79(5):444.
    PMID: 31265003 DOI: 10.1140/epjc/s10052-019-6926-x
    A search for supersymmetry is presented based on events with at least one photon, jets, and large missing transverse momentum produced in proton-proton collisions at a center-of-mass energy of 13



    Te



    . The data correspond to an integrated luminosity of 35.9



    fb

    -
    1



    and were recorded at the LHC with the CMS detector in 2016. The analysis characterizes signal-like events by categorizing the data into various signal regions based on the number of jets, the number of
    b
    -tagged jets, and the missing transverse momentum. No significant excess of events is observed with respect to the expectations from standard model processes. Limits are placed on the gluino and top squark pair production cross sections using several simplified models of supersymmetric particle production with gauge-mediated supersymmetry breaking. Depending on the model and the mass of the next-to-lightest supersymmetric particle, the production of gluinos with masses as large as 2120



    Ge



    and the production of top squarks with masses as large as 1230



    Ge



    are excluded at 95% confidence level.
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links