Displaying publications 121 - 140 of 3311 in total

Abstract:
Sort:
  1. Fulltext A comparison study of dental pulp stem cells derived from healthy and orthodontically intruded human permanent teeth for mesenchymal stem cell characterisation
    Lau MN, Kunasekaran W, On YY, Tan LJ, Zaharin NA, H A Ghani S, et al.
    PLoS One, 2022;17(12):e0279129.
    PMID: 36574419 DOI: 10.1371/journal.pone.0279129
    The objective of this study was to compare the characteristics of Dental Pulp Stem Cells (DPSCs) derived from healthy human permanent teeth with those that were orthodontically-intruded to serve as potential Mesenchymal Stem Cells (MSC). Recruited subjects were treated with orthodontic intrusion on one side of the maxillary first premolar while the opposite side served as the control for a period of six weeks before the dental pulp was extracted. Isolated DPSCs from both the control and intruded samples were analyzed, looking at the morphology, growth kinetics, cell surface marker profile, and multilineage differentiation for MSC characterisation. Our study showed that cells isolated from both groups were able to attach to the cell culture flask, exhibited fibroblast-like morphology under light microscopy, able to differentiate into osteogenic, adipogenic and chondrogenic lineages as well as tested positive for MSCs cell surface markers CD90 and CD105 but negative for haematopoietic cell surface markers CD34 and HLA-DR. Both groups displayed a trend of gradually increasing population doubling time from passage 1 to passage 5. Viable DPSCs from both groups were successfully recovered from their cryopreserved state. In conclusion, DPSCs in the dental pulp of upper premolar not only remained viable after 6 weeks of orthodontic intrusion using fixed appliances but also able to develop into MSCs.
    Matched MeSH terms: Cells, Cultured; Mesenchymal Stromal Cells*
  2. The evaluation expression of non-coding RNAs in response to HSV-G47∆ oncolytic virus infection in glioblastoma multiforme cancer stem cells
    Vazifehmand R, Ali DS, Othman Z, Chau DM, Stanslas J, Shafa M, et al.
    J Neurovirol, 2022 Dec;28(4-6):566-582.
    PMID: 35951174 DOI: 10.1007/s13365-022-01089-w
    Glioblastoma multiforme is the most aggressive astrocytes brain tumor. Glioblastoma cancer stem cells and hypoxia conditions are well-known major obstacles in treatment. Studies have revealed that non-coding RNAs serve a critical role in glioblastoma progression, invasion, and resistance to chemo-radiotherapy. The present study examined the expression levels of microRNAs (in normoxic condition) and long non-coding RNAs (in normoxic and hypoxic conditions) in glioblastoma stem cells treated with the HSV-G47∆. The expression levels of 43 miRNAs and 8 lncRNAs isolated from U251-GBM-CSCs were analyzed using a miRCURY LNA custom PCR array and a quantitative PCR assay, respectively. The data revealed that out of 43 miRNAs that only were checked in normoxic condition, the only 8 miRNAs, including miR-7-1, miR-let-7b, miR-130a, miR-137, miR-200b, miR-221, miR-222, and miR-874, were markedly upregulated. The expression levels of lncRNAs, including LEF1 antisense RNA 1 (LEF1-AS1), metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), long intergenic non-protein coding RNA 470 (LINC00470), tumor suppressor candidate 7 (TUSC7), HOX transcript antisense RNA (HOTAIR), nuclear paraspeckle assembly transcript 1 (NEAT1), and X inactive specific transcript (XIST), were markedly downregulated in the hypoxic microenvironment, and H19-imprinted maternally expressed transcript (H19) was not observed to be dysregulated in this environment. Under normoxic conditions, LEF1-AS1, MALAT1, LINC00470, H19, HOTAIR, NEAT1, and XIST were downregulated and TUSC7 was not targeted by HSV-G47∆. Overall, the present data shows HSVG47Δ treatment deregulates non-coding RNA expression in GBM-CSC tumor microenvironments.
    Matched MeSH terms: Neoplastic Stem Cells/metabolism; Neoplastic Stem Cells/pathology
  3. Fulltext A Three-Dimensional Xeno-Free Culture Condition for Wharton's Jelly-Mesenchymal Stem Cells: The Pros and Cons
    Koh B, Sulaiman N, Fauzi MB, Law JX, Ng MH, Yuan TL, et al.
    Int J Mol Sci, 2023 Feb 13;24(4).
    PMID: 36835154 DOI: 10.3390/ijms24043745
    Xeno-free three-dimensional cultures are gaining attention for mesenchymal stem cell (MSCs) expansion in clinical applications. We investigated the potential of xeno-free serum alternatives, human serum and human platelet lysate, to replace the current conventional use of foetal bovine serum for subsequent MSCs microcarrier cultures. In this study, Wharton's Jelly MSCs were cultured in nine different media combinations to identify the best xeno-free culture media for MSCs culture. Cell proliferation and viability were identified, and the cultured MSCs were characterised in accordance with the minimal criteria for defining multipotent mesenchymal stromal cells by the International Society for Cellular Therapy (ISCT). The selected culture media was then used in the microcarrier culture of MSCs to determine the potential of a three-dimensional culture system in the expansion of MSCs for future clinical applications, and to identify the immunomodulatory potential of cultured MSCs. Low Glucose DMEM (LG) + Human Platelet (HPL) lysate media appeared to be good candidates for replacing conventional MSCs culture media in our monolayer culture system. MSCs cultured in LG-HPL achieved high cell yield, with characteristics that remained as described by ISCT, although the overall mitochondrial activity of the cells was lower than the control and the subsequent effects remained unknown. MSC microcarrier culture, on the other hand, showed comparable cell characteristics with monolayer culture, yet had stagnated cell proliferation, which is potentially due to the inactivation of FAK. Nonetheless, both the MSCs monolayer culture and the microcarrier culture showed high suppressive activity on TNF-α, and only the MSC microcarrier culture has a better suppression of IL-1 secretion. In conclusion, LG-HPL was identified as a good xeno-free media for WJMSCs culture, and although further mechanistic research is needed, the results show that the xeno-free three-dimensional culture maintained MSC characteristics and improved immunomodulatory activities, suggesting the potential of translating the monolayer culture into this culture system in MSC expansion for future clinical application.
    Matched MeSH terms: Cells, Cultured; Mesenchymal Stromal Cells*
  4. Fulltext Evaluating Nuclear Membrane Irregularity for the Classification of Cervical Squamous Epithelial Cells
    Tang JR, Mat Isa NA, Ch'ng ES
    PLoS One, 2016;11(10):e0164389.
    PMID: 27741266 DOI: 10.1371/journal.pone.0164389
    Pap test involves searching of morphological changes in cervical squamous epithelial cells by pathologists or cytotechnologists to identify potential cancerous cells in the cervix. Nuclear membrane irregularity is one of the morphological changes of malignancy. This paper proposes two novel techniques for the evaluation of nuclear membrane irregularity. The first technique, namely, penalty-driven smoothing analysis, introduces different penalty values for nuclear membrane contour with different degrees of irregularity. The second technique, which can be subdivided into mean- or median-type residual-based analysis, computes the number of points of nuclear membrane contour that deviates from the mean or median of the nuclear membrane contour. Performance of the proposed techniques was compared to three state-of-the-art techniques, namely, radial asymmetric, shape factor, and rim difference. Friedman and post hoc tests using Holm, Shaffer, and Bergmann procedures returned significant differences for all the three classes, i.e., negative for intraepithelial lesion or malignancy (NILM) versus low grade squamous intraepithelial lesion (LSIL), NILM versus high grade squamous intraepithelial lesion (HSIL), and LSIL versus HSIL when the span value equaled 3 was employed with linear penalty function. When span values equaled 5, 7, and 9, NILM versus LSIL and HSIL showed significant differences regardless of the penalty functions. In addition, the results of penalty-driven smoothing analysis were comparable with those of other state-of-the-art techniques. Residual-based analysis returned significant differences for the comparison among the three diagnostic classes. Findings of this study proved the significance of nuclear membrane irregularity as one of the features to differentiate the different diagnostic classes of cervical squamous epithelial cells.
    Matched MeSH terms: Epithelial Cells/classification; Epithelial Cells/pathology*
  5. Fulltext Derivation and long-term culture of an embryonic stem cell-like line from zebrafish blastomeres under feeder-free condition
    Ho SY, Goh CW, Gan JY, Lee YS, Lam MK, Hong N, et al.
    Zebrafish, 2014 Oct;11(5):407-20.
    PMID: 24967707 DOI: 10.1089/zeb.2013.0879
    Existing zebrafish embryonic stem (ES) cell lines are derived and maintained using feeder layers. We describe here the derivation and long-term culture of an ES cell-like line derived from zebrafish blastomeres without the use of feeder cells. This line, designated as ZES1, has been maintained for more than 800 days in defined Dulbecco's modified Eagle's medium supplemented with fetal bovine serum, zebrafish embryo extract, trout serum, and human basic fibroblast growth factor. ZES1 cells possessed a morphology typical of ES cells, being round or polygonal in shape with a large nucleus and sparse cytoplasm and were mostly diploid. The cells formed individual colonies consisting of tightly packed cells that stained positively for alkaline phosphatase. ZES1 cells also formed embryoid bodies when transferred onto uncoated wells. The pluripotent nature of ZES1 cells was confirmed when they could be induced to differentiate in vitro into several cell types, through low- or high-density culture conditions. Treatment with retinoic acid also induced the differentiation of ZES1 cells into primarily neuronal cells. Using immunostaining and real-time polymerase chain reaction, we showed that Sox2, a known pluripotent marker in mammalian ES cells, was also present in ZES1 cells. Chimera experiments revealed that fluorescent-labeled ZES1 cells microinjected into zebrafish blastulas participated in the formation of all three germ layers. Using GFP-labeled ZES1 cells, chimera germline transmission was also demonstrated at the F1 generation. In conclusion, ZES1 cells possess both in vitro and in vivo pluripotency characteristics, indicating that nonmammalian ES cells can be readily derived and maintained for a long term under feeder-free culture conditions.
    Matched MeSH terms: Embryonic Stem Cells/cytology; Embryonic Stem Cells/metabolism*
  6. Insulinotropic Activity of Standardized Methanolic Extracts of Ficus deltoidea from Seven Varieties
    Yahaya N, Mohd Dom NS, Adam Z, Hamid M
    Evid Based Complement Alternat Med, 2018;2018:3769874.
    PMID: 30046337 DOI: 10.1155/2018/3769874
    Ficus deltoidea is a traditional medicinal plant that has been proven to show antidiabetic effects. This study focus is to assess the insulin secretion activity of Ficus deltoidea standardized methanolic extracts from seven independent varieties and mechanisms that underlie the insulin secretion action of the extracts. The cytotoxicity of Ficus deltoidea extracts was tested using viability assay. The insulin secretion assay was carried out by treating clonal BRIN BD11 cell line with standardized methanolic Ficus deltoidea extracts or glybenclamide. The clonal BRIN BD11 cell was also treated with insulin agonist and antagonist to elucidate the insulin secretion mechanism. Only the viability percentage for Ficus deltoidea var. kunstleri and intermedia was identified to be toxic at 500 and 1000 μg/ml (P<0.001). The insulin secretion for Ficus deltoidea var. deltoidea, angustifolia, and motleyana was dose-dependent; further evaluation suggested that Ficus deltoidea var. trengganuensis was involved in KATP-independent pathway. This study suggests that standardized methanolic extracts of Ficus deltoidea varieties have an insulinotropic effect on clonal BRIN BD11 cell line and can be utilized as a modern candidate of antidiabetic agents targeting the escalation for insulin secretion from pancreatic beta cells.
    Matched MeSH terms: Cells, Cultured; Clone Cells; Insulin-Secreting Cells
  7. Fulltext Induction of apoptosis and cell cycle blockade by helichrysetin in a549 human lung adenocarcinoma cells
    Ho YF, Karsani SA, Yong WK, Abd Malek SN
    Evid Based Complement Alternat Med, 2013;2013:857257.
    PMID: 23533528 DOI: 10.1155/2013/857257
    Researchers are looking into the potential development of natural compounds for anticancer therapy. Previous studies have postulated the cytotoxic effect of helichrysetin towards different cancer cell lines. In this study, we investigated the cytotoxic effect of helichrysetin, a naturally occurring chalcone on four selected cancer cell lines, A549, MCF-7, Ca Ski, and HT-29, and further elucidated its biochemical and molecular mechanisms in human lung adenocarcinoma, A549. Helichrysetin showed the highest cytotoxic activity against Ca Ski followed by A549. Changes in the nuclear morphology of A549 cells such as chromatin condensation and nuclear fragmentation were observed in cells treated with helichrysetin. Further evidence of apoptosis includes the externalization of phosphatidylserine and the collapse of mitochondrial membrane potential which are both early signs of apoptosis. These signs of apoptosis are related to cell cycle blockade at the S checkpoint which suggests that the alteration of the cell cycle contributes to the induction of apoptosis in A549. These results suggest that helichrysetin has great potentials for development as an anticancer agent.
    Matched MeSH terms: HT29 Cells; MCF-7 Cells; A549 Cells
  8. Fulltext Evaluation of in vitro osteoblast and osteoclast differentiation from stem cell: a systematic review of morphological assays and staining techniques
    Zainal Ariffin SH, Megat Abdul Wahab R, Abdul Razak M, Yazid MD, Shahidan MA, Miskon A, et al.
    PeerJ, 2024;12:e17790.
    PMID: 39071131 DOI: 10.7717/peerj.17790
    BACKGROUND: Understanding human stem cell differentiation into osteoblasts and osteoclasts is crucial for bone regeneration and disease modeling. Numerous morphological techniques have been employed to assess this differentiation, but a comprehensive review of their application and effectiveness is lacking.

    METHODS: Guided by the PRISMA framework, we conducted a rigorous search through the PubMed, Web of Science and Scopus databases, analyzing 254 articles. Each article was scrutinized against pre-defined inclusion criteria, yielding a refined selection of 14 studies worthy of in-depth analysis.

    RESULTS: The trends in using morphological approaches were identified for analyzing osteoblast and osteoclast differentiation. The three most used techniques for osteoblasts were Alizarin Red S (mineralization; six articles), von Kossa (mineralization; three articles) and alkaline phosphatase (ALP; two articles) followed by one article on Giemsa staining (cell morphology) and finally immunochemistry (three articles involved Vinculin, F-actin and Col1 biomarkers). For osteoclasts, tartrate-resistant acid phosphatase (TRAP staining) has the highest number of articles (six articles), followed by two articles on DAPI staining (cell morphology), and immunochemistry (two articles with VNR, Cathepsin K and TROP2. The study involved four stem cell types: peripheral blood monocyte, mesenchymal, dental pulp, and periodontal ligament.

    CONCLUSION: This review offers a valuable resource for researchers, with Alizarin Red S and TRAP staining being the most utilized morphological procedures for osteoblasts and osteoclasts, respectively. This understanding provides a foundation for future research in this rapidly changing field.

    Matched MeSH terms: Stem Cells/cytology; Stem Cells/metabolism
  9. Functionalization of poly (lactic-co-glycolic acid) nano‑calcium sulphate and fucoidan 3D scaffold using human bone marrow mesenchymal stromal cells for bone tissue engineering application
    Shaz N, Maran S, Genasan K, Choudhary R, Alias R, Swamiappan S, et al.
    Int J Biol Macromol, 2024 Jan;256(Pt 1):128059.
    PMID: 37989428 DOI: 10.1016/j.ijbiomac.2023.128059
    This study aimed to functionalize a novel porous PLGA (Poly lactic-co-glycolic acid) composite scaffold in combination with nano‑calcium sulphate (nCS) and/or fucoidan (FU) to induce osteogenic differentiation of human bone marrow stromal cells. The composite scaffolds (PLGA-nCS-FU, PLGA-nCS or PLGA-FU) were fabricated and subjected to characterization using Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), Scanning electron microscopy (SEM) and Energy Dispersive X-Ray (EDX). The biocompatibility and osteogenic induction potential of scaffolds on seeded human bone marrow derived mesenchymal stromal cells (hBMSCs) were studied using cell attachment and alamar blue cell viability and alkaline phosphatase (ALP), osteocalcin and osteogenic gene expression, respectively. The composition of different groups was reflected in FTIR, XRD and EDX. The SEM micrographs revealed a difference in the surface of the scaffold before and after FU addition. The confocal imaging and SEM micrographs confirmed the attachment of cells onto all three composite scaffolds. However, the AB assay indicated a significant increase (p 
    Matched MeSH terms: Bone Marrow Cells; Mesenchymal Stromal Cells*
  10. Fulltext Polyethylene glycol-phospholipid functionalized single-walled carbon nanotubes for enhanced siRNA systemic delivery
    Tan YF, Hii LW, Lim WM, Cheong SK, Leong CO, Yee MS, et al.
    Sci Rep, 2024 Dec 03;14(1):30098.
    PMID: 39627280 DOI: 10.1038/s41598-024-80646-1
    Small interfering RNAs (siRNA) technology has emerged as a promising therapeutic tool for human health conditions like cancer due to its ability to regulate gene silencing. Despite FDA-approved, their delivery remains localized and limiting their systemic use. This study used single-walled carbon nanotubes (SWNTs) functionalized with polyethylene glycolated (PEGylated) phospholipids (PL-PEG) derivatives for systemic siRNA delivery. We developed an siRNA systemic delivery vehicle (SWNT-siRNA) by conjugating SWNT functionalized with PL-PEG containing either amine (PA) or maleimide (MA). The functionalized SWNT with a lower molecular weight of PA produced the SWNT-siRNA conjugate system with the highest stability and high siRNA loading quantity. The system delivered siRNA to a panel of tumour cell lines of different organs (i.e. HeLa, H1299 and MCF-7) and a non-cancerous human embryonic kidney 293 cells (HEK293T) with high biocompatibility and low toxicity. The cellular uptake of SWNT-siRNA conjugates by epithelial cells was found to be energy dependent. Importantly, the presence of P-glycoprotein, a marker for drug resistance, did not inhibit SWNT-mediated siRNA delivery. Mouse xenograft model further confirmed the potential of SWNT-siRNA conjugates with a significant gene knock-down without signs of acute toxicity. These findings pave the way for potential gene therapy applications using SWNTs as delivery vehicles.
    Matched MeSH terms: HeLa Cells; HEK293 Cells; MCF-7 Cells
  11. Fulltext Cytokine factors present in dengue patient sera induces alterations of junctional proteins in human endothelial cells
    Appanna R, Wang SM, Ponnampalavanar SA, Lum LC, Sekaran SD
    Am J Trop Med Hyg, 2012 Nov;87(5):936-42.
    PMID: 22987650 DOI: 10.4269/ajtmh.2012.11-0606
    Plasma leakage in severe dengue has been postulated to be associated with skewed cytokine immune responses. In this study, the association of cytokines with vascular permeability in dengue patients was investigated. Human serum samples collected from 48 persons (13 with dengue fever, 29 with dengue hemorrhagic fever, and 6 healthy) were subjected to cytokines analysis by using Luminex Multiplex Technology. Selected serum samples from patients with dengue hemorrhagic fever sera and recombinant human cytokines were then tested for roles on inducing vascular permeability by treatment of human umbilical vein endothelial cells. Confocal immunofluorescence staining indicated morphologic alteration of human umbilical vein endothelial cells treated with serum samples from patients with dengue hemorrhagic fever compared with serum samples from healthy persons. The findings suggest that cytokines produced during dengue hemorrhagic infections could induce alterations in the vascular endothelium, which may play a fundamental role in the pathophysiology of dengue.
    Matched MeSH terms: Cells, Cultured; Endothelial Cells/metabolism
  12. Global search for right cell type as a treatment modality for cardiovascular disease
    Musa S, Xin LZ, Govindasamy V, Fuen FW, Kasim NH
    Expert Opin Biol Ther, 2014 Jan;14(1):63-73.
    PMID: 24191782 DOI: 10.1517/14712598.2014.858694
    Acute myocardial infarction is the primary cause of heart disease-related death in the world. Reperfusion therapy is currently the backbone of treatment for acute myocardial infarction albeit with many limitations. With the emergence of stem cells as potential therapeutic agents, attempts in using them to enhance cardiac function have increased exponentially. However, it has its own disadvantages, and we postulate that the primary drawback is choosing the right cell type and solving this may significantly contribute to ambitious goal of using stem cells in the regeneration medicine.
    Matched MeSH terms: Embryonic Stem Cells/transplantation*; Adult Stem Cells/transplantation*; Induced Pluripotent Stem Cells/transplantation*
  13. Fulltext Extrinsic factors involved in the differentiation of stem cells into insulin-producing cells: an overview
    Wong RS
    Exp Diabetes Res, 2011;2011:406182.
    PMID: 21747828 DOI: 10.1155/2011/406182
    Diabetes mellitus is a chronic disease with many debilitating complications. Treatment of diabetes mellitus mainly revolves around conventional oral hypoglycaemic agents and insulin replacement therapy. Recently, scientists have turned their attention to the generation of insulin-producing cells (IPCs) from stem cells of various sources. To date, many types of stem cells of human and animal origins have been successfully turned into IPCs in vitro and have been shown to exert glucose-lowering effect in vivo. However, scientists are still faced with the challenge of producing a sufficient number of IPCs that can in turn produce sufficient insulin for clinical use. A careful choice of stem cells, methods, and extrinsic factors for induction may all be contributing factors to successful production of functional beta-islet like IPCs. It is also important that the mechanism of differentiation and mechanism by which IPCs correct hyperglycaemia are carefully studied before they are used in human subjects.
    Matched MeSH terms: Cells, Cultured; Stem Cells/metabolism; Stem Cells/physiology*; Insulin-Secreting Cells/physiology*
  14. Scalable production of pancreatic islet progenitors for diabetes cell therapies
    Lock LT, Tzanakakis ES
    Med J Malaysia, 2008 Jul;63 Suppl A:5-6.
    PMID: 19024957
    Embryonic stem cells (ESCs) can be an inexhaustible source of islet cells for transplantation. Previously published protocols have been characterized by low differentiation efficiency. In this study, we developed a scalable system for the growth and differentiation of hESCs towards pancreatic islets. Our results showed that hESCs can be grown on microcarriers to a larger scale and directed to differentiate into pancreatic progenitor endoderm cells. This culture system would represent an economical differentiation protocol that can be scaled-up to meet the demand in islet transplantation.
    Matched MeSH terms: Stem Cells/cytology; Insulin-Secreting Cells; Embryonic Stem Cells/cytology*; Embryonic Stem Cells/transplantation
  15. Unique molecular signatures influencing the biological function and fate of post-natal stem cells isolated from different sources
    Abu Kasim NH, Govindasamy V, Gnanasegaran N, Musa S, Pradeep PJ, Srijaya TC, et al.
    J Tissue Eng Regen Med, 2015 Dec;9(12):E252-66.
    PMID: 23229816 DOI: 10.1002/term.1663
    The discovery of mesenchymal stem cells (MSCs) from a myriad of tissues has triggered the initiative of establishing tailor-made stem cells for disease-specific therapy. Nevertheless, lack of understanding on the inherent differential propensities of these cells may restrict their clinical outcome. Therefore, a comprehensive study was done to compare the proliferation, differentiation, expression of cell surface markers and gene profiling of stem cells isolated from different sources, viz. bone marrow, Wharton's jelly, adipose tissue and dental pulp. We found that although all MSCs were phenotypically similar to each other, Wharton's jelly (WJ) MSCs and dental pulp stem cells (DPSCs) were highly proliferative as compared to bone marrow (BM) MSCs and adipose tissue (AD) MSCs. Moreover, indistinguishable cell surface characteristics and differentiation capacity were confirmed to be similar among all cell types. Based on gene expression profiling, we postulate that BM-MSCs constitutively expressed genes related to inflammation and immunodulation, whereas genes implicated in tissue development were highly expressed in AD-MSCs. Furthermore, the transcriptome profiling of WJ-MSCs and DPSCs revealed an inherent bias towards the neuro-ectoderm lineage. Based on our findings, we believe that there is no unique master mesenchymal stem cell that is appropriate to treat all target diseases. More precisely, MSCs from different sources exhibit distinct and unique gene expression signatures that make them competent to give rise to specific lineages rather than others. Therefore, stem cells should be subjected to rigorous characterization and utmost vigilance needs to be adopted in order to choose the best cellular source for a particular disease.
    Matched MeSH terms: Bone Marrow Cells/cytology; Bone Marrow Cells/metabolism*; Mesenchymal Stromal Cells/cytology; Mesenchymal Stromal Cells/metabolism*
  16. Age and gender effect on the growth of bone marrow stromal cells in vitro
    Shamsul BS, Aminuddin BS, Ng MH, Ruszymah BH
    Med J Malaysia, 2004 May;59 Suppl B:196-7.
    PMID: 15468885
    Bone marrow harvested by aspiration contains connective tissue progenitor cells which can be selectively isolated and induced to express bone phenotype in vitro. The osteoblastic progenitor can be estimated by counting the number of cells attach using the haemacytometer. This study was undertaken to test the hypothesis that human aging is associated with a significant change on the number of osteoblastic progenitors in the bone marrow. Bone marrow aspirates were harvested from 38 patients, 14 men (age 11-70) and 24 women (age 10-70) and cultured in F12: DMEM (1:1). In total 15 bone marrow samples have been isolated from patients above 40 years old (men/women) of age. Fourteen (93.3%) of this samples failed to proliferate. Only one (6.7%) bone marrow sample from a male patient, aged 59 years old was successfully cultured. Seventy percent (16/23) of the samples from patient below than 40 years old were successfully cultured. However, our observation on the survival rate for cells of different gender from patient below 40 years old does not indicate any significant difference. From this study, we conclude that the growth of bone marrow stromal cells possibly for bone engineering is better from bone marrow aspirates of younger patient.
    Matched MeSH terms: Bone Marrow Cells/cytology*; Stromal Cells/cytology; Mesenchymal Stromal Cells/cytology*
  17. Fulltext Henipavirus pathogenesis in human respiratory epithelial cells
    Escaffre O, Borisevich V, Carmical JR, Prusak D, Prescott J, Feldmann H, et al.
    J Virol, 2013 Mar;87(6):3284-94.
    PMID: 23302882 DOI: 10.1128/JVI.02576-12
    Hendra virus (HeV) and Nipah virus (NiV) are deadly zoonotic viruses for which no vaccines or therapeutics are licensed for human use. Henipavirus infection causes severe respiratory illness and encephalitis. Although the exact route of transmission in human is unknown, epidemiological studies and in vivo studies suggest that the respiratory tract is important for virus replication. However, the target cells in the respiratory tract are unknown, as are the mechanisms by which henipaviruses can cause disease. In this study, we characterized henipavirus pathogenesis using primary cells derived from the human respiratory tract. The growth kinetics of NiV-Malaysia, NiV-Bangladesh, and HeV were determined in bronchial/tracheal epithelial cells (NHBE) and small airway epithelial cells (SAEC). In addition, host responses to infection were assessed by gene expression analysis and immunoassays. Viruses replicated efficiently in both cell types and induced large syncytia. The host response to henipavirus infection in NHBE and SAEC highlighted a difference in the inflammatory response between HeV and NiV strains as well as intrinsic differences in the ability to mount an inflammatory response between NHBE and SAEC. These responses were highest during HeV infection in SAEC, as characterized by the levels of key cytokines (interleukin 6 [IL-6], IL-8, IL-1α, monocyte chemoattractant protein 1 [MCP-1], and colony-stimulating factors) responsible for immune cell recruitment. Finally, we identified virus strain-dependent variability in type I interferon antagonism in NHBE and SAEC: NiV-Malaysia counteracted this pathway more efficiently than NiV-Bangladesh and HeV. These results provide crucial new information in the understanding of henipavirus pathogenesis in the human respiratory tract at an early stage of infection.
    Matched MeSH terms: Cells, Cultured; Epithelial Cells/immunology*; Epithelial Cells/virology*; Giant Cells/virology
  18. Epithelial membrane antigen (EMA) or MUC1 expression in monocytes and monoblasts
    Leong CF, Raudhawati O, Cheong SK, Sivagengei K, Noor Hamidah H
    Pathology, 2003 Oct;35(5):422-7.
    PMID: 14555387
    AIMS: Epithelial membrane antigen (EMA) or MUC1 belongs to a heterogeneous group of heavily glycosylated proteins and is expressed in most normal and epithelial neoplastic cells. EMA is also expressed in plasma cells, anaplastic large cell lymphoma (Ki-1 antigen), malignant histiocytosis and erythroleukaemia. In 1996, Cheong et al. (Hematology 1996; 1: 223) demonstrated the positive expression of EMA in monoblasts. Since there were very few useful markers for differentiating subtypes of acute myeloid leukaemia with a monocytic component from the those without, a study was conducted to evaluate the prevalence of EMA expression and its relationship with known markers for monocytic-macrophage lineage (CD11c, CD14 and intracellular CD68) in monocytes and monoblasts.

    METHODS: EMA detection was performed by flow cytometry in monocytes and monoblasts. EMA expression was compared with other known markers of monocytic-macrophage lineage (CD11c, CD14 and intracellular CD68). Samples of purified monocytes were obtained from 20 healthy volunteers. Twenty-two cases of monocytic AML (M4 and M5) were studied and controls were selected from 20 cases of acute lymphoblastic leukaemia (ALL) and 18 cases of non-monocytic AML (M0, M1, M2, M3, and M7).

    RESULTS: EMA was shown to be expressed strongly on the surface of all purified monocytes. EMA expression was observed on blast cells in 18/22 (81.8%) cases of AML M4 and M5, but not in that of non-monocytic AML or ALL. In this study EMA monoclonal antibody has demonstrated a strong association (P<0.001) with all the other known markers of monocytic-macrophage lineage in acute leukaemia subtypes. EMA had also shown 100% specificity and 81.8% sensitivity in the diagnosis of AML M4 and M5.

    CONCLUSIONS: The monoclonal antibody EMA (clone E29) is a useful marker in the classification of acute myeloid leukaemia and can be used as a supplementary analysis for the diagnosis of acute leukemia with monocytic involvement.

    Matched MeSH terms: Bone Marrow Cells/metabolism; Bone Marrow Cells/pathology; Stem Cells/metabolism*; Stem Cells/pathology
  19. In vitro differentiation of mesenchymal stem cells into mesangial cells when co-cultured with injured mesangial cells
    Wong CY, Tan EL, Cheong SK
    Cell Biol Int, 2014 Apr;38(4):497-501.
    PMID: 24375917 DOI: 10.1002/cbin.10231
    Mesangial cells are one of the three major cell types of the kidney glomerulus that provide physical support for the glomerular capillary lumen of the kidney. Loss of mesangial cells due to pathologic conditions, such as glomerulonephritis and diabetic nephropathy, can impair renal function. Mesenchymal stem cells (MSC) are attractive candidates for kidney repair therapy since they can enhance recovery and protect against kidney failure. MSC can differentiate into mesangial cells in vivo. We have investigated the ability of MSC to differentiate into mesangial cells in vitro; they were co-cultured with oxidant-injured mesangial cells before being analysed by flow cytometry and for contractility. MSC co-cultured with injured mesangial cells had a mesangial cell-like morphology and contracted in response to angiotensin II. They expressed CD54(-) CD62E(+) in direct contrast to the CD54(+) CD62E(-) of pure MSC. In conclusion, MSC can differentiate into mesangial cells in vitro when co-cultured with injured mesangial cells.
    Matched MeSH terms: Cells, Cultured; Mesangial Cells/cytology*; Mesangial Cells/pathology; Mesenchymal Stromal Cells/cytology*
  20. Fulltext Impaired NK Cell Activation and Chemotaxis toward Dendritic Cells Exposed to Complement-Opsonized HIV-1
    Ellegård R, Crisci E, Andersson J, Shankar EM, Nyström S, Hinkula J, et al.
    J Immunol, 2015 Aug 15;195(4):1698-704.
    PMID: 26157174 DOI: 10.4049/jimmunol.1500618
    Mucosa resident dendritic cells (DCs) may represent one of the first immune cells that HIV-1 encounters during sexual transmission. The virions in body fluids can be opsonized with complement factors because of HIV-mediated triggering of the complement cascade, and this appears to influence numerous aspects of the immune defense targeting the virus. One key attribute of host defense is the ability to attract immune cells to the site of infection. In this study, we investigated whether the opsonization of HIV with complement (C-HIV) or a mixture of complement and Abs (CI-HIV) affected the cytokine and chemokine responses generated by DCs, as well as their ability to attract other immune cells. We found that the expression levels of CXCL8, CXCL10, CCL3, and CCL17 were lowered after exposure to either C-HIV or CI-HIV relative to free HIV (F-HIV). DCs exposed to F-HIV induced higher cell migration, consisting mainly of NK cells, compared with opsonized virus, and the chemotaxis of NK cells was dependent on CCL3 and CXCL10. NK cell exposure to supernatants derived from HIV-exposed DCs showed that F-HIV induced phenotypic activation (e.g., increased levels of TIM3, CD69, and CD25) and effector function (e.g., production of IFNγ and killing of target cells) in NK cells, whereas C-HIV and CI-HIV did not. The impairment of NK cell recruitment by DCs exposed to complement-opsonized HIV and the lack of NK activation may contribute to the failure of innate immune responses to control HIV at the site of initial mucosa infection.
    Matched MeSH terms: Dendritic Cells/immunology*; Dendritic Cells/metabolism; Killer Cells, Natural/immunology*; Killer Cells, Natural/metabolism
Related Terms
Filters
Contact Us

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

External Links