82 research outputs found
Distinct RNA profiles in subpopulations of extracellular vesicles: apoptotic bodies, microvesicles and exosomes
No full textIntroduction: 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
Tactical avoidance of statistics? – How students choose methods in writing theses in interdisciplinary higher education programmes
No full textEldh discusses the challenges in teaching quantitative methods, in this case statistics, in interdisciplinary courses with mixed methods where both qualitative and quantitative methods are taught. Despite this, most students tend to choose to use qualitative methods in their thesis research and the author researches why this is the case. Literature suggests that students often find statistics courses to be daunting and that students may lack motivation. However, the author finds that in this case the challenges have more to do with the framing of the course in the programme, the instructions from supervisors to their students and the competency of teaching staff when it comes to methods other than the ones they themselves promote. The findings and discussion highlight the importance of collegial communication and mutual understanding
Taktiskt undvikande av statistik? -Hur studenter väljer metod i uppsatsarbete på en tvärvetenskapligt universitetsutbildning n
No full textEldh discusses the challenges in teaching quantitative methods, in this case statistics, in interdisciplinary courses with mixed methods where both qualitative and quantitative methods are taught. Despite this, most students tend to choose to use qualitative methods in their thesis research and the author researches why this is the case. Literature suggests that students often find statistics courses to be daunting and that students may lack motivation. However, the author finds that in this case the challenges have more to do with the framing of the course in the programme, the instructions from supervisors to their students and the competency of teaching staff when it comes to methods other than the ones they themselves promote. The findings and discussion highlight the importance of collegial communication and mutual understanding
Exosomes and Exosomal RNA – A Way of Cell-to-Cell Communication
No full textExosomes are nano-sized extracellular vesicles of endocytic origin participating in cell-to-cell
communication, partly by the transfer of exosomal RNA between cells. These extracellular
vesicles are released by most cells and found in many body fluids including plasma and urine.
Exosomes differ compared to their donor cells in RNA, protein and lipid composition, and
their molecular content has shown prognostic and diagnostic potential. Uveal melanoma is a
tumour arising from melanocytes of the eye and despite successful control of the primary
tumour, approximately one third of the patients will develop metastases, predominantly liver
metastases, with poor prognosis. The overall aim of this thesis was to evaluate the role of
exosomes in cell-to-cell communication and the biological role of exosomal RNA.
Exosomal RNA has been extracted by different RNA isolation methods and we identified that
the RNA size distribution pattern varied in multiple studies. Therefore, we aimed to determine
if this RNA variation was a true variation or merely a consequence of the RNA extraction
method used. We evaluated seven different RNA isolation methods using a mouse mast cell
line (MC/9) that continuously releases exosomes. The results showed that the exosomal RNA
yield and size distribution pattern differed substantially between different RNA isolation
methods.
The mRNA content and function of MC/9 cell-derived exosomes was shown to be altered
depending on the culture conditions of the cells. Cells exposed to oxidative stress were shown
to have the capacity to send a conditioning signal to other cells, resulting in resistance to
oxidative stress in the recipient cells. Moreover, this conditioning signal was shown to be
eradicated upon UV-C exposure, indicating a possible role for the exosomal RNA in this
biological function.
The presence of exosomes in patients with liver metastases from uveal melanoma was
established with the isolation, detection and characterisation of exosomes from isolated
hepatic perfusion. The results revealed melanoma-specific exosomes, which contained similar
microRNA profiles between patients. Furthermore, patients with metastatic uveal melanoma
were shown to have a higher concentration of exosomes in their peripheral venous blood
compared to healthy controls.
We conclude that exosomes play a role in cell-to-cell communication and their RNA appears
to be of biological importance. Furthermore, exosomal RNA may potentially play a role in the
diagnosis and prognosis of uveal melanoma
Automatic Quality Assurance and Release (Dagstuhl Seminar 18122)
No full textThis report documents the program and the outcomes of Dagstuhl Seminar 18122 "Automatic Quality Assurance and Release". The main goal of this seminar was to bridge the knowledge divide on how researchers and industry professionals reason about and implement DevOps for automatic quality assurance. Through the seminar, we have built up a common understanding of DevOps tools and practices, but we have also identified major academic and educational challenges for this field of research
Morgonbris : tidning för den socialdemokratiska kvinnorörelsen (Årg. 11, N:r 4)
No full textNär du nämnes...1
Se dig omkring! Karl Esper 2
"För fred och folkförbrödring". (Forts.) Maria Larsen 3
Kvinnornas internationella dag. 4
Från Norge. Anna Lindhagen 5
Gertrud Månsson. A. St. 5
"Femme de trottoir". Carl Eldh 6
Understöd åt änkors barn. A.L. 6
Kvinnans plats efter världskriget. Hannes Sköld 7
Från våra kvinnoklubbar i Ultima Thule. I. Kata D-m. 8
Hunger. Karl Östman 8
Stora framsteg i barnavårdslagstiftningen i Norge. Anna Lindhagen 9
Från kvinnoklubbarnas arbetsfält. 1
Flyttfåglar - en kvalitativ studie av flyktingbarns upplevelser av krig, flykt och exil
No full textThe aim of this study was to explore refugee children’s psychological experiences of forced migration and exile in Sweden. Eleven semi structured interviews were conducted with children age 7-16. The interviews covered three main areas: life in the native country, the journey of migration, and life in Sweden. The children’s narratives were analyzed in accordance with IPA(Interpretative Phenomenological Analysis). The analysis resulted in eleven clusters of themes which covered the children’s narratives of: pre-war life and good memories; life under the threats of war; daily life during war; forced migration; arrival in Sweden; view of Sweden and the native country; life in Sweden; how they related to having family and friends left behind in their native country; how they related to the negative things about the native country; being refused asylum; and the future. The results indicated that the children had difficult experiences from the war, and sometimes also from the journey of migration. The exile in Sweden involved both positive and negative experiences. The children’s narratives showed different ways in which they related to and coped with experiences from their native country and experiences of exile in Sweden. The study showed a difference in experiences and coping strategies between the children who had been granted permanent residence and those who had been refused asylum
Extracellular vesicles for immunotherapy and tumor profiling
No full textExtracellular vesicles are particles secreted by cells and mediators of intercellular communication, carrying a diverse cargo of lipids, nucleic acids, proteins and metabolites. The specific cargo and function of EVs depends on the cell of origin. EVs from dendritic cells (DC) loaded with tumor antigens induced anti-tumor CD8+ T cell responses and reduced tumor growth in mice. Studies have reported that EVs from human and cow's milk have anti-inflammatory effects and promote barrier functions. EVs from cancer cells can be detected in biofluids and may be useful tools for cancer diagnosis, prognosis and disease monitoring.Adequate T cell priming and infiltration into the tumor improve the efficacy of PD- 1- and PD-L1-targeted immune checkpoint blockade ICB). Therefore, T cell responses generated by antigen-loaded (Ag-loaded) DC EVs have the potential to enhance the response to PD-1 and PD-L1 blockade. In addition, T cell responses to Ag-loaded EVs are dependent on B cells. In study I, we investigated a combination of Ag-loaded DC EVs with ICB of PD-1 or PD-L1. Therapeutically administered EVs did not improve the response to ICB in mice, but prophylactic administration of EVs strongly increased the survival of mice receiving therapeutic PD-L1 blockade. In study II, we used a fusion protein to target EVs specifically to B cells through human CD21. This targeting increased the Ag-specific CD8+ T cell expansion, which can indicate an increased anti-tumor potential.In study II, we explored the use of bovine milk-derived EVs for antigen delivery and Ag-specific immunomodulation. EVs from bovine serum were studied in comparison. We achieved loading of the model antigen ovalbumin (OVA) into EVs, and these EVs increased OVA-specific CD4+ T cell proliferation compared to free OVA in vitro and in vivo. In vitro, OVA-loaded serum EVs induced a different phenotype of activated CD4+ T cells compared to OVA-loaded milk EVs or free OVA.In study IV, we analyzed the protein content of urinary EVs from urinary bladder cancer (UBC) patients and non-UBC controls using proximity extension assay. We identified a UBC-specific signature and were able to distinguish muscle invasive UBC compared to non-muscle-invasive UBC, supporting EVs as biomarkers.In conclusion, this thesis increases our understanding of the therapeutic and diagnostic potential of EVs.List of scientific papersI. Rosanne E. Veerman, Gozde Gucluler Akpinar, Annemarijn Offens, Loïc Steiner, Pia Larssen, Andreas Lundqvist, Mikael C.I. Karlsson, Susanne Gabrielsson. Antigen-loaded extracellular vesicles induce responsiveness to anti-PD-1 and anti-PD-L1 treatment in a checkpoint refractory melanoma model. Cancer Immunology Research. 11 217-227 (2023). https://doi.org/10.1158/2326-6066.cir-22-0540II. Annemarijn Offens, Loes Teeuwen, Gozde Gucluler Akpinar, Loïc Steiner, Sander Kooijmans, Doste Mamand, Hannah Weissinger, Alexander Käll, Maria Eldh, Oscar P.B Wiklander, Samir EL Andaloussi, Mikael C.I. Karlsson, Pieter Vader, Susanne Gabrielsson. A fusion protein that targets antigen-loaded extracellular vesicles to B cells enhances antigen-specific T cell expansion. [Manuscript]III. Extracellular vesicles from bovine milk and serum can be loaded with protein antigen by lyophilization and induce CD4+ T cell responses in mice. Annemarijn Offens, Maria Eldh, Loes Teeuwen, Gozde Gucluler Akpinar, Loïc Steiner, Rebeca Cardoso, Monisha Samuel, Eduardo Villablanca, Susanne Gabrielsson. [Manuscript]IV. Loïc Steiner, Maria Eldh, Annemarijn Offens, Rosanne E. Veerman, Markus Johansson, Tammer Hemdan, Hans Netterling, Ylva Huge, Abdul-Sattar Aljabery Firas, Farhood Alamdari, Oskar Liden, Amir Sherif and Susanne Gabrielsson. Protein profile in urinary extracellular vesicles is a marker of malignancy and correlates with muscle invasiveness in urinary bladder cancer. Cancer Letters. 609, 217352 (2025). https://doi.org/10.1016/j.canlet.2024.217352</p
Isolation and Characterization of RNA-Containing Exosomes
No full textThe 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 erythrocytes1, 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 membrane2. 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 milk3-6. 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 allergen7,8, eradication of established tumors in mice9, inhibition and activation of natural killer cells10-12, promotion of differentiation into T regulatory cells13, stimulation of T cell proliferation14 and induction of T cell apoptosis15. 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 o
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