| 1. |
- Asif, Sana, et al.
(författare)
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Oxygen-charged HTK-F6H8 emulsion reduces ischemia : reperfusion injury in kidneys from brain-dead pigs
- 2012
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Ingår i: Journal of Surgical Research. - : Elsevier BV. - 0022-4804 .- 1095-8673. ; 178:2, s. 959-967
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Tidskriftsartikel (refereegranskat)abstract
- Background:Prolonged cold ischemia is frequently associated with a greater risk of delayed graft function and enhanced graft failure. We hypothesized that media, combining a high oxygen-dissolving capacity with specific qualities of organ preservation solutions, would be more efficient in reducing immediate ischemia-reperfusion injury from organs stored long term compared with standard preservation media.Methods:Kidneys retrieved from brain-dead pigs were flushed using either cold histidine-tryptophan-ketoglutarate (HTK) or oxygen-precharged emulsion composed of 75% HTK and 25% perfluorohexyloctane. After 18 h of cold ischemia the kidneys were transplanted into allogeneic recipients and assessed for adenosine triphosphate content, morphology, and expression of genes related to hypoxia, environmental stress, inflammation, and apoptosis.Results:Compared with HTK-flushed kidneys, organs preserved using oxygen-precharged HTK-perfluorohexyloctane emulsion had increased elevated adenosine triphosphate content and a significantly lower gene expression of hypoxia inducible factor-1 alpha, vascular endothelial growth factor, interleukin-1 alpha, tumor necrosis factor-alpha, interferon-alpha, JNK-1, p38, cytochrome-c, Bax, caspase-8, and caspase-3 at all time points assessed. In contrast, the mRNA expression of Bcl-2 was significantly increased.Conclusions:The present study has demonstrated that in brain-dead pigs the perfusion of kidneys with oxygen-precharged HTK-perfluorohexyloctane emulsion results in significantly reduced inflammation, hypoxic injury, and apoptosis and cellular integrity and energy content are well maintained. Histologic examination revealed less tubular, vascular, and glomerular changes in the emulsion-perfused tissue compared with the HTK-perfused counterparts. The concept of perfusing organs with oxygen-precharged emulsion based on organ preservation media represents an efficient alternative for improved organ preservation.
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| 2. |
- Babiker, Adil A., et al.
(författare)
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Mapping pro- and antiangiogenic factors on the surface of prostasomes of normal and malignant cell origin
- 2010
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Ingår i: The Prostate. - : Wiley. - 0270-4137 .- 1097-0045. ; 70:8, s. 834-847
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Angiogenesis is the formation of new blood vessels by capillary sprouting from pre-existing vessels. Tumor growth is angiogenesis-dependent and the formation of new blood vessels is associated with the increased expression of angiogenic factors. Prostasomes are secretory granules produced, stored and released by the glandular epithelial cells of the prostate. We investigated the expression of selected angiogenic and anti-angiogenic factors on the surface of prostasomes of different origins as well as the direct effect of prostasomes on angiogenesis. METHODS: VEGF, endothelin-1, endostatin, and thrombospondin-1 were determined on prostasomes from seminal fluid and human prostate cancer cell lines (DU145,PC-3,LNCaP) using different immunochemical techniques. Human dermal microvascular endothelial cells were incubated with seminal and DU145 cell-prostasomes and with radioactive thymidine. The effect of prostasomes on angiogenesis was judged by measuring the uptake of labeled thymidine. The presence of any deleterious effects of prostasomes on the endothelial cells was investigated using thymidine assay and confocal laser microscopy. RESULTS: VEGF and endothelin-1 were determined on malignant cell-prostasomes (no difference between cell lines) but not determined on seminal prostasomes. The same applies for the expression of endostatin but with much higher expression on malignant cell-prostasomes with obvious differences between them. Seminal and DU145 cell-prostasomes were found to have anti-angiogenic effect which was more expressed by DU145 cell-prostasomes. No deleterious effect of prostasomes on endothelial function was detected using either thymidine assay or microscopy. CONCLUSIONS: Prostasomes contain pro- and anti-angiogenic factors that function to counteract each other unless the impact from one side exceeds the other to bring about dysequilibrium.
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| 3. |
- Cabric, Sanja, et al.
(författare)
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Anchoring of vascular endothelial growth factor to surface-immobilized heparin on pancreatic islets : implications for stimulating islet angiogenesis
- 2010
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Ingår i: Tissue engineering. Part A. - : Mary Ann Liebert Inc. - 1937-3341 .- 1937-335X. ; 16:3, s. 961-970
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Tidskriftsartikel (refereegranskat)abstract
- In pancreatic islet transplantation, early revascularization is necessary for long-term graft function. We have shown in in vitro and in vivo models that modification with surface-attached heparin protects the islets from acute attack by the innate immune system of the blood following intraportal islet transplantation. In this study, we have investigated the ability of an immobilized conjugate composed of heparin to bind the angiogenic growth factor vascular endothelial growth factor-A (VEGF-A) as a means of attracting endothelial cells (ECs) to induce angiogenesis and revascularization. We analyzed the capacity of VEGF-A to bind to immobilized heparin and how this affected the proliferation and adherence of ECs to both artificial glass surfaces and islets. Quartz crystal microbalance with dissipation monitoring and slot-blot demonstrated the binding of VEGF-A to heparin-coated surfaces upon which ECs showed protein-dependent proliferation. Also, ECs cultured on heparin-coated glass surfaces exhibited effects upon focal contacts. Heparinized islets combined with VEGF-A demonstrated unaffected insulin release. Further, covering islets with heparin also increased the adhesion of ECs to the islet surface. Immobilized heparin on the islet surface may be a useful anchor molecule for achieving complete coverage of islets with angiogenic growth factors, ultimately improving islet revascularization and engraftment in pancreatic islet transplantation.
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| 4. |
- Duprez, Ida Rasmusson, et al.
(författare)
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Preparatory studies of composite mesenchymal stem cell islets for application in intraportal islet transplantation
- 2011
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Ingår i: Upsala Journal of Medical Sciences. - : Uppsala Medical Society. - 0300-9734 .- 2000-1967. ; 116:1, s. 8-17
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Tidskriftsartikel (refereegranskat)abstract
- Abstract Background. Low engraftment and adverse immune reactions hamper the success rate of clinical islet transplantation. In this study, we investigated the capacity of human mesenchymal stem cells (MSCs) to adhere to human islets of Langerhans and their effects in immune modulation and during blood interactions in vitro. Methods. Composite MSC-islets were formed by suspension co-culture, and the phenotype was evaluated by confocal microscopy. Islet function was assessed by dynamic insulin release in response to glucose in vitro. Mixed lymphocyte-islet reactions (MLIR) and the tubing blood loop model were utilized as in vitro tools to analyse the effect of MSCs on the innate and adaptive immune reactions triggered by the islets. Results. MSCs rapidly adhered to islets and spread out to cover the islet surface. Insulin expression and secretion were sustained with the MSC coating. MSC-coated islets showed unaffected reactions with blood in vitro in comparison to control islets. Furthermore, MSCs suppressed lymphocyte proliferation induced by islet cells in MLIR. Conclusion. We conclude that it is possible to create composite MSC-islets to enable delivery of the MSCs by utilizing the adhesive capacity of the MSCs. This could have beneficial immunosuppressive effects in optimizing pancreatic islet transplantation.
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| 5. |
- Edin, Fredrik, et al.
(författare)
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3-D gel culture and time-lapse video microscopy of the human vestibular nerve
- 2014
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Ingår i: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 134:12, s. 1211-1218
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Tidskriftsartikel (refereegranskat)abstract
- UNLABELLED: Abstract Conclusions: Human inner ear neurons have an innate regenerative capacity and can be cultured in vitro in a 3-D gel. The culture technique is valuable for experimental investigations of human inner ear neuron signaling and regeneration.OBJECTIVES: To establish a new in vitro model to study human inner ear nerve signaling and regeneration.METHODS: Human superior vestibular ganglion (SVG) was harvested during translabyrinthine surgery for removal of vestibular schwannoma. After dissection tissue explants were embedded and cultured in a laminin-based 3-D matrix (Matrigel™). 3-D growth cone (GC) expansion was analyzed using time-lapse video microscopy (TLVM). Neural marker expression was appraised using immunocytochemistry with fluorescence and laser confocal microscopy.RESULTS: Tissue explants from adult human SVG could be cultured in 3-D in a gel, indicating an innate potential for regeneration. Cultured GCs were found to expand dynamically in the gel. Growth cone expansion and axonal Schwann cell alignment were documented using TLVM. Neurons were identified morphologically and through immunohistochemical staining.
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| 6. |
- Edin, Fredrik, et al.
(författare)
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Differentiation of human neural progenitor cell-derived spiral ganglion-like neurons : a time-lapse video study
- 2014
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Ingår i: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 134:5, s. 441-447
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Tidskriftsartikel (refereegranskat)abstract
- Conclusions: Human neural progenitor cells can differentiate into spiral ganglion-like cells when exposed to inner ear-associated growth factors. The phenotype bears resemblance to human sphere-derived neurons. Objective: To establish an in vitro model for the human auditory nerve to replace and complement in vivo animal experiments and ultimately human in vivo transplantation. Methods: Human neural progenitors were differentiated under conditions developed for in vitro survival of human primary spiral ganglion culture with media containing growth factors associated with inner ear development. Differentiation was documented using time-lapse video microscopy. Time-dependent marker expression was evaluated using immunocytochemistry with fluorescence and laser confocal microscopy. Results: Within 14 days of differentiation, neural progenitors adopted neural phenotype and expressed spiral ganglion-associated markers.
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| 7. |
- Fransson, Moa, et al.
(författare)
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CAR/FoxP3-engineered T regulatory cells target the CNS and suppress EAE upon intranasal delivery
- 2012
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Ingår i: Journal of Neuroinflammation. - : Springer Science and Business Media LLC. - 1742-2094. ; 9, s. 112-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS). In the murine experimental autoimmune encephalomyelitis (EAE) model of MS, T regulatory (Treg) cell therapy has proved to be beneficial, but generation of stable CNS-targeting Tregs needs further development. Here, we propose gene engineering to achieve CNS-targeting Tregs from naive CD4 cells and demonstrate their efficacy in the EAE model.METHODSCD4+T cells were modified utilizing a lentiviral vector system to express a chimeric antigen receptor (CAR) targeting myelin oligodendrocyte glycoprotein (MOG) in trans with the murine FoxP3 gene that drives Treg differentiation. The cells were evaluated in vitro for suppressive capacity and in C57BL/6 mice to treat EAE. Cells were administered by intranasal (i.n.) cell delivery.RESULTSThe engineered Tregs demonstrated suppressive capacity in vitro and could efficiently access various regions in the brain via i.n cell delivery. Clinical score 3 EAE mice were treated and the engineered Tregs suppressed ongoing encephalomyelitis as demonstrated by reduced disease symptoms as well as decreased IL-12 and IFNgamma mRNAs in brain tissue. Immunohistochemical markers for myelination (MBP) and reactive astrogliosis (GFAP) confirmed recovery in mice treated with engineered Tregs compared to controls. Symptomfree mice were echallenged with a second EAE-inducing inoculum but remained healthy, demonstrating the sustained effect of engineered Tregs.CONCLUSIONCNS-targeting Tregs delivered i.n. localized to the CNS and efficiently suppressed ongoing inflammation leading to diminished disease symptoms.
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| 8. |
- Fransson, Moa, et al.
(författare)
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Intranasal Delivery of CNS-Retargeted Human Mesenchymal Stromal Cells Prolongs Treatment Efficacy of Experimental Autoimmune Encephalomyelitis
- 2014
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Ingår i: Immunology. - : Wiley. - 0019-2805 .- 1365-2567. ; 142:3, s. 431-441
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Tidskriftsartikel (refereegranskat)abstract
- Treatment with mesenchymal stromal cells (MSC) is currently of interest for a number of diseases including multiple sclerosis (MS). MSCs is well known to target inflamed tissues however, in a therapeutic scenery, systemic administration will lead to few cells reaching the brain. We hypothesized that MSCs may target the brain upon intranasal (i.n) administration and persist in CNS tissue if expressing a CNS-targeting receptor. To demonstrate proof of concept, MSCs were genetically engineered to express a myelin oligodendrocyte glycoprotein (MOG)-specific receptor. Engineered MSCs retained their immunosuppressive capacity, infiltrated into the brain upon i.n. cell administration, and were able to significantly reduce disease symptoms of experimental autoimmune encephalomyelitis (EAE). The mice treated with CNS-targeting MSCs were resistant to further EAE induction whereas non-targeted MSC did not give such persistent effects. Histological analysis revealed increased brain restoration in engineered MSC-treated mice. In conclusion, MSCs can be genetically engineered to target the brain and prolong therapeutic efficacy in an EAE model.
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| 9. |
- Moll, Guido, et al.
(författare)
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Are Therapeutic Human Mesenchymal Stromal Cells Compatible with Human Blood?
- 2012
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Ingår i: Stem Cells. - : Oxford University Press (OUP). - 1066-5099 .- 1549-4918. ; 30:7, s. 1565-1574
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Tidskriftsartikel (refereegranskat)abstract
- Multipotent mesenchymal stromal cells (MSCs) are tested in numerous clinical trials. Questions have been raised concerning fate and function of these therapeutic cells after systemic infusion. We therefore asked whether culture-expanded human MSCs elicit an innate immune attack, termed instant blood-mediated inflammatory reaction (IBMIR), which has previously been shown to compromise the survival and function of systemically infused islet cells and hepatocytes. We found that MSCs expressed hemostatic regulators similar to those produced by endothelial cells but displayed higher amounts of prothrombotic tissue/stromal factors on their surface, which triggered the IBMIR after blood exposure, as characterized by formation of blood activation markers. This process was dependent on the cell dose, the choice of MSC donor, and particularly the cell-passage number. Short-term expanded MSCs triggered only weak blood responses in vitro, whereas extended culture and coculture with activated lymphocytes increased their prothrombotic properties. After systemic infusion to patients, we found increased formation of blood activation markers, but no formation of hyperfibrinolysis marker D-dimer or acute-phase reactants with the currently applied dose of 1.0-3.0 x 10(6) cells per kilogram. Culture-expanded MSCs trigger the IBMIR in vitro and in vivo. Induction of IBMIR is dose-dependent and increases after prolonged ex vivo expansion. Currently applied doses of low-passage clinical-grade MSCs elicit only minor systemic effects, but higher cell doses and particularly higher passage cells should be handled with care. This deleterious reaction can compromise the survival, engraftment, and function of these therapeutic cells.
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| 10. |
- Nilsson, Per H., et al.
(författare)
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Autoregulation of thromboinflammation on biomaterial surfaces by a multicomponent therapeutic coating
- 2013
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Ingår i: Biomaterials. - : Elsevier BV. - 0142-9612 .- 1878-5905. ; 34:4, s. 985-994
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Tidskriftsartikel (refereegranskat)abstract
- Activation of the thrombotic and complement systems is the main recognition and effector mechanisms in the multiple adverse biological responses triggered when biomaterials or therapeutic cells come into blood contact. We have created a surface which is auto-protective to human innate immunity by combining three fundamentally different strategies, all developed by us previously, which have been shown to induce substantial, but incomplete hemocompatibility when used separately. In summary, we have conjugated a factor H-binding peptide; and an ADP-degrading enzyme; using a PEG linker on both material and cellular surfaces. When exposed to human whole blood, factor H was specifically recruited to the modified surfaces and inhibited complement attack. In addition, activation of platelets and coagulation was efficiently attenuated, by degrading ADP. Thus, by inhibiting thromboinflammation using a multicomponent approach, we have created a hybrid surface with the potential to greatly reduce incompatibility reactions involving biomaterials and transplantation.
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| 11. |
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