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  1. Article ; Online: Plasma-based COVID-19 treatments in low-and middle-income countries and the risk of transfusion-transmitted infections

    Jay Epstein / W. Martin Smid / Silvano Wendel / Daniel Somuah / Thierry Burnouf

    npj Vaccines, Vol 5, Iss 1, Pp 1-

    2020  Volume 2

    Abstract: Ethical principles should prevail in the collection, testing and use of COVID-19 convalescent plasma (CCP) for human research in low- and middle- income countries. To appropriately guarantee safety, only blood establishments that comply with recognized ... ...

    Abstract Ethical principles should prevail in the collection, testing and use of COVID-19 convalescent plasma (CCP) for human research in low- and middle- income countries. To appropriately guarantee safety, only blood establishments that comply with recognized quality standards should collect CCP.
    Keywords Immunologic diseases. Allergy ; RC581-607 ; Neoplasms. Tumors. Oncology. Including cancer and carcinogens ; RC254-282 ; covid19
    Language English
    Publishing date 2020-11-01T00:00:00Z
    Publisher Nature Publishing Group
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Reflections on Dry Eye Syndrome Treatment

    Victor J. Drew / Ching-Li Tseng / Jerard Seghatchian / Thierry Burnouf

    Frontiers in Medicine, Vol

    Therapeutic Role of Blood Products

    2018  Volume 5

    Abstract: Dry eye syndrome (DES) is a multifactorial, frequent, pathology characterized by deficient tear production or increased evaporation of tears and associated with ocular surface alteration and inflammation. It mostly affects, but not exclusively, older ... ...

    Abstract Dry eye syndrome (DES) is a multifactorial, frequent, pathology characterized by deficient tear production or increased evaporation of tears and associated with ocular surface alteration and inflammation. It mostly affects, but not exclusively, older individuals and leads to varying degrees of discomfort and decreased quality of life. Although the typical treatments of DES rely on using artificial tears, polyunsaturated fatty acids, integrin antagonists, anti-inflammatory agents, or on performing punctal occlusion, recently, standardized blood-derived serum eye drops (SED) are generating much interest as a new physiological treatment option. The scientific rationale in using SED for treating or releasing the symptoms of DES is thought to lie in its composition in multiple factors that resembles that of tears and contributes to the healing and protection of the ocular surface. This manuscript seeks to provide relevant background information on the management of DES, and on the increasing role that various types of SED or platelet lysates, from autologous or allogeneic origins, are playing in the improved therapeutic management of this pathology. The increasing role played by blood establishments in producing better-standardized SED is also addressed.
    Keywords dry eye syndrome ; keratoconjunctivitis ; artificial tears ; serum eye drop ; platelet lysate ; blood ; Medicine (General) ; R5-920
    Subject code 630
    Language English
    Publishing date 2018-02-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article: Four types of human platelet lysate, including one virally inactivated by solvent-detergent, can be used to propagate Wharton jelly mesenchymal stromal cells

    Chen, Ming-Sheng / Hsiu-Chen Lin / Thierry Burnouf / Tsung-Jen Wang

    New biotechnology. 2019 Mar. 25, v. 49

    2019  

    Abstract: There is accumulating experimental evidence that human platelet lysate (HPL) made from platelet concentrates can replace fetal bovine serum (FBS) as a xeno-free clinical-grade supplement of growth media to expand mesenchymal stromal cells (MSCs). However, ...

    Abstract There is accumulating experimental evidence that human platelet lysate (HPL) made from platelet concentrates can replace fetal bovine serum (FBS) as a xeno-free clinical-grade supplement of growth media to expand mesenchymal stromal cells (MSCs). However, uncertainties exist in regard to impacts that various manufacturing methods of HPL can exert on the expansion and differentiation capacity of MSCs. In particular, there is a need to evaluate the possibility of implementing virus-inactivation treatment during HPL production to ensure optimal safety of industrial HPL pools. Expired human platelet concentrates from four different donors were pooled and subjected to freeze-thaw cycles (-80/+37 °C), followed or not by serum-conversion by calcium chloride, heat-treatment at 56 °C for 30 min, or solvent-detergent (S/D) virus inactivation. The concentrations of total proteins, growth factors and fibrinogen, and the chemical compositions of the HPLs were characterized. The impact of HPL supplementation on the cell morphology, doubling time, immunophenotype and trilineage differentiation capacity of Wharton jelly MSCs (WJMSCs) were compared over five passages, using FBS as a control and normalizing the protein content. Data showed that WJMSCs expanded equally well, exhibited a typical fibroblast morphology, had short doubling times, maintained their immunophenotypes, and differentiated into chondrocyte, osteocyte, and adipocyte lineages in all HPL-supplemented media, all of which were more effective than FBS. In conclusion, we found minimal detectable impact of the HPL manufacturing process, including S/D virus inactivation, on the suitability of expanding WJMSCs in vitro.
    Keywords adipocytes ; calcium chloride ; culture media ; fetal bovine serum ; fibrinogen ; fibroblasts ; freeze-thaw cycles ; growth factors ; heat treatment ; humans ; manufacturing ; mesenchymal stromal cells ; protein content ; uncertainty ; viruses
    Language English
    Dates of publication 2019-0325
    Size p. 151-160.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 2400836-9
    ISSN 1876-4347 ; 1871-6784
    ISSN (online) 1876-4347
    ISSN 1871-6784
    DOI 10.1016/j.nbt.2018.11.003
    Database NAL-Catalogue (AGRICOLA)

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  4. Article ; Online: Clinical-grade cryopreserved doxorubicin-loaded platelets

    Yu-Wen Wu / Cheng-Chain Huang / Chun Austin Changou / Long-Sheng Lu / Hadi Goubran / Thierry Burnouf

    Journal of Biomedical Science, Vol 27, Iss 1, Pp 1-

    role of cancer cells and platelet extracellular vesicles activation loop

    2020  Volume 16

    Abstract: Abstract Background Human platelets (PLT) and PLT-extracellular vesicles (PEV) released upon thrombin activation express receptors that interact with tumour cells and, thus, can serve as a delivery platform of anti-cancer agents. Drug-loaded ... ...

    Abstract Abstract Background Human platelets (PLT) and PLT-extracellular vesicles (PEV) released upon thrombin activation express receptors that interact with tumour cells and, thus, can serve as a delivery platform of anti-cancer agents. Drug-loaded nanoparticles coated with PLT membranes were demonstrated to have improved targeting efficiency to tumours, but remain impractical for clinical translation. PLT and PEV targeted drug delivery vehicles should facilitate clinical developments if clinical-grade procedures can be developed. Methods PLT from therapeutic-grade PLT concentrate (PC; N > 50) were loaded with doxorubicin (DOX) and stored at − 80 °C (DOX-loaded PLT) with 6% dimethyl sulfoxide (cryopreserved DOX-loaded PLT). Surface markers and function of cryopreserved DOX-loaded PLT was confirmed by Western blot and thromboelastography, respectively. The morphology of fresh and cryopreserved naïve and DOX-loaded PLT was observed by scanning electron microscopy. The content of tissue factor-expressing cancer-derived extracellular vesicles (TF-EV) present in conditioned medium (CM) of breast cancer cells cultures was measured. The drug release by fresh and cryopreserved DOX-loaded PLT triggered by various pH and CM was determined by high performance liquid chromatography. The thrombin activated PEV was analyzed by nanoparticle tracking analysis. The cellular uptake of DOX from PLT was observed by deconvolution microscopy. The cytotoxicities of DOX-loaded PLT, cryopreserved DOX-loaded PLT, DOX and liposomal DOX on breast, lung and colon cancer cells were analyzed by CCK-8 assay. Results 15~36 × 106 molecules of DOX could be loaded in each PLT within 3 to 9 days after collection. The characterization and bioreactivity of cryopreserved DOX-loaded PLT were preserved, as evidenced by (a) microscopic observations, (b) preservation of important PLT membrane markers CD41, CD61, protease activated receptor-1, (c) functional activity, (d) reactivity to TF-EV, and (e) efficient generation of PEV upon thrombin activation. The ...
    Keywords Cryopreserved platelet ; Tissue factor ; Cancer ; Doxorubicin ; Platelet extracellular vesicles ; Drug delivery ; Medicine ; R
    Subject code 610 ; 500
    Language English
    Publishing date 2020-03-01T00:00:00Z
    Publisher BMC
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Ex vivo expansion of bovine corneal endothelial cells in xeno-free medium supplemented with platelet releasate.

    Ming-Li Chou / Thierry Burnouf / Tsung-Jen Wang

    PLoS ONE, Vol 9, Iss 6, p e

    2014  Volume 99145

    Abstract: Clinical-grade ex vivo expansion of corneal endothelial cells can increase the availability of corneal tissues for transplantation and treatment of corneal blindness. However, these cells have very limited proliferative capacity. Successful propagation ... ...

    Abstract Clinical-grade ex vivo expansion of corneal endothelial cells can increase the availability of corneal tissues for transplantation and treatment of corneal blindness. However, these cells have very limited proliferative capacity. Successful propagation has required so far to use very complex growth media supplemented with fetal bovine serum and other xenocomponents. We hypothesized that human platelet releasates rich in multiple growth factors, and in particular neurotrophins, could potentially be a useful supplement for ex vivo expansion of corneal endothelium cells due to their neural crest origin. Platelet releasates were prepared by calcium salt activation of apheresis platelet concentrates, subjected or not to complement inactivation by heat treatment at 56°C for 30 minutes. Platelet releasates were characterized for their content in proteins and were found to contain high amount of growth factors including platelet-derived growth factor-AB (30.56 to 39.08 ng/ml) and brain-derived neurotrophic factor (30.57 to 37.11 ng/ml) neurotrophins. We compared the growth and viability of corneal endothelium cells in DMEM-F12 medium supplemented with different combinations of components, including 2.5%∼10% of the platelet releasates. Corneal endothelium cells expanded in platelet releasates exhibited good adhesion and a typical hexagonal morphology. Their growth and viability were enhanced when using the complement-inactivated platelet releasate at a concentration of 10%. Immunostaining and Western blots showed that CECs maintained the expressions of four important membrane markers: Na-K ATPase α1, zona occludens-1, phospho-connexin 43 and N-cadherin. In conclusion, our study provides the first proof-of-concept that human platelet releasates can be used for ex vivo expansion of corneal endothelium cells. These findings open a new paradigm for ex vivo propagation protocols of corneal endothelium cells in compliance with good tissue culture practices and regulatory recommendations to limit the use of xenogenic materials.
    Keywords Medicine ; R ; Science ; Q
    Subject code 570
    Language English
    Publishing date 2014-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Anti-Human Platelet Antigen-1a Immunoglobulin G Preparation Intended to Prevent Fetal and Neonatal Alloimmune Thrombocytopenia.

    Ying-Jan Weng / Anne Husebekk / Björn Skogen / Mette Kjaer / Liang-Tzung Lin / Thierry Burnouf

    PLoS ONE, Vol 11, Iss 9, p e

    2016  Volume 0162973

    Abstract: Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a severe disease that is caused by maternal alloantibodies generated during pregnancy or at delivery as a result of incompatibility between maternal and fetal human platelet antigens (HPAs) ... ...

    Abstract Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a severe disease that is caused by maternal alloantibodies generated during pregnancy or at delivery as a result of incompatibility between maternal and fetal human platelet antigens (HPAs) inherited from the father. Antibody-mediated immune suppression using anti-HPA-1a immunoglobulins is thought to be able to prevent FNAIT caused by HPA-1a. A fractionation process to prepare anti-HPA-1a immunoglobulin (Ig) G (IgG) from human plasma was therefore developed. Anti-HPA-1a plasma was obtained from volunteer mothers who underwent alloimmunization against HPA-1a during a previous pregnancy. Plasma was cryoprecipitated and the supernatant treated with caprylic acid and solvent/detergent (S/D), purified by chromatography, nanofiltered, concentrated, and sterile-filtered. The anti-HPA-1a immunoglobulin fraction was characterized for purity and safety. PAK12 and quantitative monoclonal antibody immobilization of platelet antigen (MAIPA) assays were used to detect anti-HPA-1a IgG. Hepatitis C virus (HCV) removal during nanofiltration was assessed by spiking experiments, using cell culture-derived reporter HCV and luciferase analysis. The caprylic acid treatment precipitated non-Ig proteins yielding a 90% pure Ig supernatant. S-HyperCel chromatography of the S/D-treated supernatant followed by HyperCel STAR AX provided high IgG recovery (>80%) and purity (>99.5%), and efficient IgA and IgM removal. Concentrations of complement factors C3 and C4 were < 0.5 and < 0.4 mg/dL, respectively. The final IgG could be nanofiltered on Planova 20N under conditions removing more than 3 log HCV infectivity to baseline mock infection level, and concentrated to ca. 30 g/L. Proteolytic activity and thrombin generation were low in the final fraction. The Pak12 and MAIPA assays showed good recovery of anti-HPA-1a throughout the process. Clinical-grade HPA-1a IgG can be prepared using a process compliant with current quality requirements opening perspectives for the ...
    Keywords Medicine ; R ; Science ; Q
    Subject code 616
    Language English
    Publishing date 2016-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: Solvent/Detergent Virally Inactivated Serum Eye Drops Restore Healthy Ocular Epithelium in a Rabbit Model of Dry-Eye Syndrome.

    Ching-Li Tseng / Zhi-Yu Chen / Ting-Yi Renn / Shun-Hung Hsiao / Thierry Burnouf

    PLoS ONE, Vol 11, Iss 4, p e

    2016  Volume 0153573

    Abstract: Application of autologous serum eye drops (SEDs) is a recognized means to treat severe dry-eye syndrome (DES). Due to the inconvenience and difficulty of preparing SEDs from some patients, producing SEDs from allogeneic blood donations is gaining ... ...

    Abstract Application of autologous serum eye drops (SEDs) is a recognized means to treat severe dry-eye syndrome (DES). Due to the inconvenience and difficulty of preparing SEDs from some patients, producing SEDs from allogeneic blood donations is gaining popularity. A major safety concern associated with allogeneic blood is virus transmission. We therefore herein evaluated the possibility of applying a solvent/detergent (S/D) treatment to inactivate viruses and studied the impacts of such treatment of SEDs to resolve DES in a rabbit model. Sera prepared from the blood of five rabbits were pooled and divided into two sub-pools. One was untreated (SEDs), while the other was virally-inactivated with 1% Tri-n-butyl phosphate/1% Triton X-45 at 31°C for 1 h (S/D-SEDs). DES was induced in rabbits using 0.1% benzalkonium chloride (BAC). Rabbits were divided into five groups of two rabbits each. One group was untreated (control), three were treated twice daily for 3 weeks using PBS, SEDs, or S/D-SEDs, and the last received an additional 0.1% BAC (as the negative control). The DES condition was determined by measuring aqueous tear secretion (Schirmer's test), corneal fluorescein staining, a corneal histologic examination, TUNEL stain apoptosis, and corneal inflammatory marker (tumor necrosis factor-α, interleukin (IL)-1β, IL-8, and IL-6) expressions. We first confirmed that SEDs and S/D-SEDs had similar protein profiles and transforming growth factor (TGF)-β contents. Animal experiments showed that tear secretion did not significantly differ between the SED and S/D-SED groups but was significantly higher than in the PBS group. Eye fluorescein staining revealed dramatic improvements in epithelial defects in groups treated with SEDs or S/D-SEDs, and hematoxylin/eosin staining revealed microscopic epithelial layers similar to those of the untreated controls. Inflammatory markers and TUNEL studies showed that healthy epithelium had been restored in groups treated with SEDs or S/D-SEDs. In conclusion, this preclinical study supports ...
    Keywords Medicine ; R ; Science ; Q
    Subject code 630
    Language English
    Publishing date 2016-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Natural scrub typhus antibody suppresses HIV CXCR4(X4) viruses

    George Watt / Pacharee Kantipong / Thierry Burnouf / Cecilia Shikuma / Sean Philpott

    Infectious Disease Reports, Vol 5, Iss 1, Pp e8-e

    2013  Volume 8

    Abstract: Viral load generally rises in HIV-infected individuals with a concomitant infection, but falls markedly in some individuals with scrub typhus (ST), a common Asian rickettsial infection. ST infection appears to shift the viral population from CXCR4-using ( ...

    Abstract Viral load generally rises in HIV-infected individuals with a concomitant infection, but falls markedly in some individuals with scrub typhus (ST), a common Asian rickettsial infection. ST infection appears to shift the viral population from CXCR4-using (X4) to CCR5-utilizing (R5) strains, and there is evidence of cross-reactivity between ST-specific antibodies and HIV-1. We examined the mechanism of ST suppression of HIV by measuring the effects of ST infection on X4 and R5 viruses in vivo and in vitro , and assessing the relative contributions of antibodies and chemokines to the inhibitory effect. In vivo , a single scrub typhus plasma infusion markedly reduced the subpopulation of HIV-1 viruses using the X4 co-receptor in all 8 recipients, and eliminated X4 viruses 6 patients. In vitro , the 14 ST sera tested all inhibited the replication of an X4 but not an R5 virus. This inhibitory effect was maintained if ST sera were depleted of chemokines but was lost upon removal of antibodies. Sera from ST-infected mice recognized a target that co-localized with X4 HIV gp120 in immunofluorescent experiments. These in vivo and in vitro data suggest that acute ST infection generates cross-reactive antibodies that produce potent suppression of CXCR4- but not CCR5-using HIV-1 viruses. ST suppression of HIV replication could reveal novel mechanisms that could be exploited for vaccination strategies, as well as aid in the development of fusion inhibitors and other new therapeutic regimens. This also appears to be the first instance where one pathogen is neutralized by antibody produced in response to infection by a completely unrelated organism.
    Keywords HIV-1 ; scrub typhus ; antibody ; Orientia tsutsugamushi ; AIDS ; Other systems of medicine ; RZ201-999
    Subject code 570
    Language English
    Publishing date 2013-05-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Removal of transmissible spongiform encephalopathy prion from large volumes of cell culture media supplemented with fetal bovine serum by using hollow fiber anion-exchange membrane chromatography.

    Ming Li Chou / Andy Bailey / Tiffany Avory / Junji Tanimoto / Thierry Burnouf

    PLoS ONE, Vol 10, Iss 4, p e

    2015  Volume 0122300

    Abstract: Cases of variant Creutzfeldt-Jakob disease in people who had consumed contaminated meat products from cattle with bovine spongiform encephalopathy emphasize the need for measures aimed at preventing the transmission of the pathogenic prion protein (PrPSc) ...

    Abstract Cases of variant Creutzfeldt-Jakob disease in people who had consumed contaminated meat products from cattle with bovine spongiform encephalopathy emphasize the need for measures aimed at preventing the transmission of the pathogenic prion protein (PrPSc) from materials derived from cattle. Highly stringent scrutiny is required for fetal bovine serum (FBS), a growth-medium supplement used in the production of parenteral vaccines and therapeutic recombinant proteins and in the ex vivo expansion of stem cells for transplantation. One such approach is the implementation of manufacturing steps dedicated to removing PrPSc from materials containing FBS. We evaluated the use of the QyuSpeed D (QSD) adsorbent hollow-fiber anion-exchange chromatographic column (Asahi Kasei Medical, Tokyo, Japan) for the removal of PrPSc from cell culture media supplemented with FBS. We first established that QSD filtration had no adverse effect on the chemical composition of various types of culture media supplemented with 10% FBS or the growth and viability characteristics of human embryonic kidney (HEK293) cells, baby hamster kidney (BHK-21) cells, African green monkey kidney (Vero) cells, and Chinese hamster ovary (CHO-k1) cells propagated in the various culture-medium filtrates. We used a 0.6-mL QSD column for removing PrPSc from up to 1000 mL of Dulbecco's modified Eagle's medium containing 10% FBS previously spiked with the 263K strain of hamster-adapted scrapie. The Western blot analysis, validated alongside an infectivity assay, revealed that the level of PrPSc in the initial 200mL flow-through was reduced by 2.5 to > 3 log10, compared with that of the starting material. These results indicate that QSD filtration removes PrPSc from cell culture media containing 10% FBS, and demonstrate the ease with which QSD filtration can be implemented in at industrial-scale to improve the safety of vaccines, therapeutic recombinant proteins, and ex vivo expanded stem cells produced using growth media supplemented with FBS.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2015-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Regulation of Tumor Growth and Metastasis

    Hadi A. Goubran / Rami R. Kotb / Julie Stakiw / Mohamed E. Emara / Thierry Burnouf

    Cancer Growth and Metastasis, Vol 2014, Iss 7, Pp 9-

    The Role of Tumor Microenvironment

    2014  Volume 18

    Keywords Neoplasms. Tumors. Oncology. Including cancer and carcinogens ; RC254-282 ; Internal medicine ; RC31-1245 ; Medicine ; R
    Language English
    Publishing date 2014-06-01T00:00:00Z
    Publisher Libertas Academica
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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