| 1. |
- Andersson, Anders, et al.
(författare)
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Effects of Tobacco Smoke on IL-16 in CD8+ Cells from Human Airways and Blood: a Key Role for Oxygen Free Radicals?
- 2011
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Ingår i: AJP - Lung cellular and molecular physiology. - : American Physiological Society. - 1522-1504. ; 300:1
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Tidskriftsartikel (refereegranskat)abstract
- Chronic exposure to tobacco smoke leads to an increase in the frequency of infections and in CD8(+) and CD4(+)cells as well as the CD4(+) chemo-attractant cytokine IL-16 in the airways. Here, we investigated whether tobacco smoke depletes intracellular IL-16 protein and inhibits de novo production of IL-16 in CD8(+) cells from human airways and blood, while at the same time increasing extracellular IL-16 and whether oxygen free radicals (OFR) are involved. Intracellular IL-16 protein in CD8(+) cells and mRNA in all cells was decreased in bronchoalveolar lavage (BAL) samples from chronic smokers. This was also the case in human blood CD8(+) cells exposed to water-soluble tobacco smoke components in vitro; in which oxidized proteins were markedly increased. Extracellular IL-16 protein was increased in cell-free BAL fluid from chronic smokers and in human blood CD8(+) cells exposed to water-soluble tobacco smoke components in vitro. This was not observed in occasional smokers after short-term exposure to tobacco smoke. A marker of activation (CD69) was slightly increased whereas other markers of key cellular functions (membrane integrity, apoptosis and proliferation) in human blood CD8(+) cells in vitro were negatively affected by water-soluble tobacco smoke components. An OFR scavenger prevented these effects whereas a protein synthesis inhibitor, a beta-adrenoceptor, a glucocorticoid receptor agonist, a phosphodiesterase, a calcineurin phosphatase and a caspase-3 inhibitor did not. In conclusion, tobacco smoke depletes preformed intracellular IL-16 protein, inhibits its de novo synthesis and distorts key cellular functions in human CD8(+) cells. OFR may play a key role in this context.
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| 2. |
- Crescitelli, Rossella, 1985, et al.
(författare)
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Distinct RNA profiles in subpopulations of extracellular vesicles: apoptotic bodies, microvesicles and exosomes.
- 2013
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Ingår i: Journal of extracellular vesicles. - : Wiley. - 2001-3078. ; 2
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: In recent years, there has been an exponential increase in the number of studies aiming to understand the biology of exosomes, as well as other extracellular vesicles. However, classification of membrane vesicles and the appropriate protocols for their isolation are still under intense discussion and investigation. When isolating vesicles, it is crucial to use systems that are able to separate them, to avoid cross-contamination. METHOD: EVS RELEASED FROM THREE DIFFERENT KINDS OF CELL LINES: HMC-1, TF-1 and BV-2 were isolated using two centrifugation-based protocols. In protocol 1, apoptotic bodies were collected at 2,000×g, followed by filtering the supernatant through 0.8 µm pores and pelleting of microvesicles at 12,200×g. In protocol 2, apoptotic bodies and microvesicles were collected together at 16,500×g, followed by filtering of the supernatant through 0.2 µm pores and pelleting of exosomes at 120,000×g. Extracellular vesicles were analyzed by transmission electron microscopy, flow cytometry and the RNA profiles were investigated using a Bioanalyzer(®). RESULTS: RNA profiles showed that ribosomal RNA was primary detectable in apoptotic bodies and smaller RNAs without prominent ribosomal RNA peaks in exosomes. In contrast, microvesicles contained little or no RNA except for microvesicles collected from TF-1 cell cultures. The different vesicle pellets showed highly different distribution of size, shape and electron density with typical apoptotic body, microvesicle and exosome characteristics when analyzed by transmission electron microscopy. Flow cytometry revealed the presence of CD63 and CD81 in all vesicles investigated, as well as CD9 except in the TF-1-derived vesicles, as these cells do not express CD9. CONCLUSIONS: Our results demonstrate that centrifugation-based protocols are simple and fast systems to distinguish subpopulations of extracellular vesicles. Different vesicles show different RNA profiles and morphological characteristics, but they are indistinguishable using CD63-coated beads for flow cytometry analysis.
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| 3. |
- Ekström, Karin, 1978, et al.
(författare)
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Characterization of mRNA and microRNA in human mast cell-derived exosomes and their transfer to other mast cells and blood CD34 progenitor cells
- 2012
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Ingår i: Journal of Extracellular Vesicles (JEV). - : Wiley. - 2001-3078. ; 1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Exosomes are nanosized vesicles of endocytic origin that are released into the extracellular environment by many different cells. It has been shown that exosomes from various cellular origins contain a substantial amount of RNA (mainly mRNA and microRNA). More importantly, exosomes are capable of delivering their RNA content to target cells, which is a novel way of cell-to-cell communication. The aim of 20 this study was to evaluate whether exosomal shuttle RNA could play a role in the communication between human mast cells and between human mast cells and human CD34+progenitor cells. Methods: The mRNA and microRNA content of exosomes from a human mast cell line, HMC-1, was analysed by using microarray technology. Co-culture experiments followed by flow cytometry analysis and confocal microscopy as well as radioactive labeling experiments were performed to examine the uptake of 25 these exosomes and the shuttle of the RNA to other mast cells and CD34+ progenitor cells. Results: In this study, we show that human mast cells release RNA-containing exosomes, with the capacity to shuttle RNA between cells. Interestingly, by using microRNA microarray analysis, 116 microRNAs could be identified in the exosomes and 134 microRNAs in the donor mast cells. Furthermore, DNA microarray experiments revealed the presence of approximately 1800 mRNAs in the exosomes, which represent 15% of 30 the donor cell mRNA content. In addition, transfer experiments revealed that exosomes can shuttle RNA between human mast cells and to CD34+ hematopoietic progenitor cells. Conclusion: These findings suggest that exosomal shuttle RNA (esRNA) can play a role in the communication between cells, including mast cells and CD34+ progenitor cells, implying a role in cells maturation process. 35
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| 4. |
- Eldh, Maria, 1980, et al.
(författare)
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Exosomes Communicate Protective Messages during Oxidative Stress; Possible Role of Exosomal Shuttle RNA.
- 2010
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Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 5:12
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Tidskriftsartikel (refereegranskat)abstract
- Exosomes are small extracellular nanovesicles of endocytic origin that mediate different signals between cells, by surface interactions and by shuttling functional RNA from one cell to another. Exosomes are released by many cells including mast cells, dendritic cells, macrophages, epithelial cells and tumour cells. Exosomes differ compared to their donor cells, not only in size, but also in their RNA, protein and lipid composition.
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| 5. |
- Eldh, Maria, 1980, et al.
(författare)
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Importance of RNA isolation methods for analysis of exosomal RNA: Evaluation of different methods
- 2012
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Ingår i: Molecular Immunology. - : Elsevier BV. - 0161-5890. ; 50:4, s. 278-286
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Tidskriftsartikel (refereegranskat)abstract
- Exosomes are small RNA containing vesicles of endocytic origin, which can take part in cell-to-cell communication partly by the transfer of exosomal RNA between cells. Exosomes are released by many cells and can also be found in several biological fluids including blood plasma and breast milk. Exosomes differ compared to their donor cells not only in size but also in RNA, protein and lipid composition. The aim of the current study was to determine the optimal RNA extraction method for analysis of exosomal RNA, to support future studies determining the biological roles of the exosomal RNA. Different methods were used to extract exosomal and cellular RNA. All methods evaluated extracted high quality and purity RNA as determined by RNA integrity number (RIN) and OD values for cellular RNA using capillary electrophoresis and spectrophotometer. Interestingly, the exosomal RNA yield differed substantially between the different RNA isolation methods. There was also a difference in the exosomal RNA patterns in the electropherograms, indicating that the tested methods extract exosomal RNA with different size distribution. A pure column based approach resulted in the highest RNA yield and the broadest RNA size distribution, whereas phenol and combined phenol and column based approaches lost primarily large RNAs. Moreover, the use of phenol and combined techniques resulted in reduced yield of exosomal RNA, with a more narrow size distribution pattern resulting in an enrichment of small RNA including microRNA. In conclusion, the current study presents a unique comparison of seven different methods for extraction of exosomal RNA. As the different isolation methods give extensive variation in exosomal RNA yield and patterns, it is crucial to select an isolation approach depending on the research question at hand.
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| 6. |
- Eldh, Maria, 1980, et al.
(författare)
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MicroRNA in exosomes isolated directly from the liver circulation in patients with metastatic uveal melanoma
- 2014
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Ingår i: BMC Cancer. - London : Springer Science and Business Media LLC. - 1471-2407. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- Uveal melanoma is a tumour arising from melanocytes of the eye, and 30 per cent of these patients develop liver metastases. Exosomes are small RNA containing nano-vesicles released by most cells, including malignant melanoma cells. This clinical translational study included patients undergoing isolated hepatic perfusion (IHP) for metastatic uveal melanoma, from whom exosomes were isolated directly from liver perfusates. The objective was to determine whether exosomes are present in the liver circulation, and to ascertain whether these may originate from melanoma cells.
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| 7. |
- Lässer, Cecilia, 1981, et al.
(författare)
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Human saliva, plasma and breast milk exosomes contain RNA: uptake by macrophages.
- 2011
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Ingår i: Journal of Translational Medicine. - : Springer Science and Business Media LLC. - 1479-5876. ; 9:9
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Exosomes are 30-100 nm membrane vesicles of endocytic origin produced by numerous cells. They can mediate diverse biological functions, including antigen presentation. Exosomes have recently been shown to contain functional RNA, which can be delivered to other cells. Exosomes may thus mediate biological functions either by surface-to-surface interactions with cells, or by the delivery of functional RNA to cells. Our aim was therefore to determine the presence of RNA in exosomes from human saliva, plasma and breast milk and whether these exosomes can be taken up by macrophages. METHOD: Exosomes were purified from human saliva, plasma and breast milk using ultracentrifugation and filtration steps. Exosomes were detected by electron microscopy and examined by flow cytometry. Flow cytometry was performed by capturing the exosomes on anti-MHC class II coated beads, and further stain with anti-CD9, anti-CD63 or anti-CD81. Breast milk exosomes were further analysed for the presence of Hsc70, CD81 and calnexin by Western blot. Total RNA was detected with a Bioanalyzer and mRNA was identified by the synthesis of cDNA using an oligo (dT) primer and analysed with a Bioanalyzer. The uptake of PKH67-labelled saliva and breast milk exosomes by macrophages was examined by measuring fluorescence using flow cytometry and fluorescence microscopy. RESULTS: RNA was detected in exosomes from all three body fluids. A portion of the detected RNA in plasma exosomes was characterised as mRNA. Our result extends the characterisation of exosomes in healthy humans and confirms the presence of RNA in human saliva and plasma exosomes and reports for the first time the presence of RNA in breast milk exosomes. Our results also show that the saliva and breast milk exosomes can be taken up by human macrophages. CONCLUSIONS: Exosomes in saliva, plasma and breast milk all contain RNA, confirming previous findings that exosomes from several sources contain RNA. Furthermore, exosomes are readily taken up by macrophages, supporting the notion that exosomal RNA can be shuttled between cells.
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| 8. |
- Lässer, Cecilia, 1981, et al.
(författare)
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Isolation and characterization of RNA-containing exosomes.
- 2012
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Ingår i: Journal of Visualized Experiments (JoVE). - : MyJove Corporation. - 1940-087X. ; 59
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Tidskriftsartikel (refereegranskat)abstract
- The field of exosome research is rapidly expanding, with a dramatic increase in publications in recent years. These small vesicles (30-100 nm) of endocytic origin were first proposed to function as a way for reticulocytes to eradicate the transferrin receptor while maturing into erythrocytes, and were later named exosomes. Exosomes are formed by inward budding of late endosomes, producing multivesicular bodies (MVBs), and are released into the environment by fusion of the MVBs with the plasma membrane. Since the first discovery of exosomes, a wide range of cells have been shown to release these vesicles. Exosomes have also been detected in several biological fluids, including plasma, nasal lavage fluid, saliva and breast milk. Furthermore, it has been demonstrated that the content and function of exosomes depends on the originating cell and the conditions under which they are produced. A variety of functions have been demonstrated for exosomes, such as induction of tolerance against allergen, eradication of established tumors in mice, inhibition and activation of natural killer cells, promotion of differentiation into T regulatory cells, stimulation of T cell proliferation and induction of T cell apoptosis. Year 2007 we demonstrated that exosomes released from mast cells contain messenger RNA (mRNA) and microRNA (miRNA), and that the RNA can be shuttled from one cell to another via exosomes. In the recipient cells, the mRNA shuttled by exosomes was shown to be translated into protein, suggesting a regulatory function of the transferred RNA. Further, we have also shown that exosomes derived from cells grown under oxidative stress can induce tolerance against further stress in recipient cells and thus suggest a biological function of the exosomal shuttle RNA. Cell culture media and biological fluids contain a mixture of vesicles and shed fragments. A high quality isolation method for exosomes, followed by characterization and identification of the exosomes and their content, is therefore crucial to distinguish exosomes from other vesicles and particles. Here, we present a method for the isolation of exosomes from both cell culture medium and body fluids. This isolation method is based on repeated centrifugation and filtration steps, followed by a final ultracentrifugation step in which the exosomes are pelleted. Important methods to identify the exosomes and characterize the exosomal morphology and protein content are highlighted, including electron microscopy, flow cytometry and Western blot. The purification of the total exosomal RNA is based on spin column chromatography and the exosomal RNA yield and size distribution is analyzed using a Bioanalyzer.
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| 9. |
- Lässer, Cecilia, 1981, et al.
(författare)
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The Role of Exosomal Shuttle RNA (esRNA) in Cell-to-Cell Communication
- 2013
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Ingår i: Emerging Concepts of Tumor Exosome–Mediated Cell-Cell Communication. - New York, NY : Springer. - 9781461436966 ; , s. 33-45
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Cell-to-cell communication can occur in several ways, with or without cell contact. Exosomes play a role in one of the most recently discovered and versatile cell-to-cell communications, which do not require cell contact and that can act over long distances. The RNA content, mRNA and microRNA, is protected by the exosomes rigid membranes, which makes it possible for cells to communicate long-distance RNA messages via the circulation system. Their mRNA content differs substantially from their mother cell mRNA content, whereas their microRNA content seems to reflect their cellular origin more. This chapter reviews the role of exosomes in cell-to-cell communication and in particular the role of exosomal shuttle RNA (esRNA). This is a new and rapidly expanding field of research that has given cell-to-cell communication an increased complexity and that has great potential within both diagnostic and therapeutic applications.
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| 10. |
- Malmhäll, Carina, 1959, et al.
(författare)
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MicroRNA-155 is essential for TH2-mediated allergen-induced eosinophilic inflammation in the lung.
- 2014
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Ingår i: Journal of Allergy and Clinical Immunology. - : Elsevier BV. - 0091-6749. ; 133:5, s. 1429-1438
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Allergic asthma is a chronic disease of the conducting airways characterized by TH2 inflammation and tissue remodeling after exposure to inhaled allergens. Although the TH2 profile is undisputed, the underlying molecular mechanisms leading to this abnormal TH2 profile remain largely unclear. MicroRNAs (miRNAs) are short noncoding RNAs that are important regulators of gene expression in the immune system. However, the role of miRNAs, specifically miR-155, in the regulation of allergic airway inflammation is unexplored. OBJECTIVES: We sought to assess the contribution of miR-155 in a mouse model of allergic airway inflammation. METHODS: To investigate a role for miR-155 in the regulation of allergic inflammation in vivo, we used miR-155 knockout (KO) and wild-type (WT) mice sensitized and exposed to ovalbumin. RESULTS: miR-155 deficiency resulted in diminished eosinophilic inflammation and mucus hypersecretion in the lungs of allergen-sensitized and allergen-challenged mice compared with WT control animals. This was supported by a reduction in TH2 cell numbers and airway TH2 cytokine levels and complete abrogation of allergen-induced airway eotaxin-2/CCL24 and periostin levels in miR-155 KO mice. Intranasal instillation of eotaxin-2/CCL24 before allergen challenge partially restored airway eosinophilia in miR-155 KO mice, and adoptive transfer of CD4(+) T cells resulted in a similar degree of airway eosinophilia in miR-155 KO and WT mice. Furthermore, the transcription factor PU.1, a negative regulator of TH2 cytokine production, was upregulated in the airways of allergen-challenged miR-155 KO mice compared with WT mice. CONCLUSIONS: Our data provides evidence that miR-155 contributes to the regulation of allergic airway inflammation by modulating TH2 responses through the transcription factor PU.1.
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| 11. |
- Rupert, Deborah, 1986, et al.
(författare)
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Determination of exosome concentration in solution using surface plasmon resonance spectroscopy.
- 2014
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Ingår i: Analytical Chemistry. - : American Chemical Society (ACS). - 0003-2700 .- 1520-6882. ; 86:12, s. 5929-5936
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Tidskriftsartikel (refereegranskat)abstract
- Exosomes are cell-secreted nanometer-sized extracellular vesicles that have been reported to play an important role in intercellular communication. They are also considered potential diagnostic markers for various health disorders, and intense investigations are presently directed towards their use as carriers in drug-delivery and gene-therapy applications. This has generated a growing need for sensitive methods capable of accurately and specifically determining the concentration of exosomes in complex biological fluids. Here, we explore the use of label-free surface-based sensing with surface plasmon resonance (SPR) read-out to determine the concentration of exosomes in solution. Human mast cell secreted exosomes carrying the tetraspanin membrane protein CD63 were analyzed by measuring their diffusion-limited binding rate to an SPR sensor surface functionalized with anti-CD63 antibodies. The concentration of suspended exosomes was determined by first converting the SPR response into surface-bound mass. The increase in mass uptake over time was then related to the exosome concentration in solution using a formalism describing diffusion-limited binding under controlled flow conditions. The proposed quantification method is based on a calibration and control measurements performed with proteins and synthetic lipid vesicles and takes into account i) the influence of the broad size distribution of the exosomes on the surface coverage, ii) the fact that their size is comparable to the ~150 nm probing depth of SPR, and iii) possible deformation of exosomes upon adsorption. Under those considerations, the accuracy of the concentration determination was estimated to be better than ±50% and significantly better if exosome deformation is negligible.
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