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Haematopoiesis dysregulation with the presence of immature myeloid and erythroid immunosuppressive cells are key characteristics of the immune escape phase of tumour development. Here, the role of in vitro generated B16F10 tumour cell-derived extracellular vesicles (tEVs) as indirect cellular communicators, participating in tumour-induced dysregulation of haematopoiesis, was explored. The isolated tEVs displayed features of small EVs with a size range of 100-200 nm, expressed the common EV markers CD63, CD9, and Alix, and had a spherical shape with a lipid bilayer membrane. Proteomic profiling revealed significant levels of angiogenic factors, particularly vascular endothelial growth factor (VEGF), osteopontin, and tissue factor, associated with the tEVs. Systemic administration of these tEVs in syngeneic mice induced splenomegaly and disrupted haematopoiesis, leading to extramedullary haematopoiesis, expansion of splenic immature erythroid progenitors, reduced bone marrow cellularity, medullary expansion of granulocytic myeloid suppressor cells, and the development of anaemia. These effects closely mirrored those observed in tumour-bearing mice and were not seen after heat inactivating the tEVs. In vitro studies demonstrated that tEVs independently induced the expansion of bone marrow granulocytic myeloid suppressor cells and B cells while reducing the frequency of cells in the erythropoietic lineage. These effects of tEVs were significantly abrogated by the blockade of VEGF or heat inactivation. Our findings underscore the important role of tEVs in dysregulating haematopoiesis during the immune escape phase of cancer immunoediting, suggesting their potential as targets for addressing immune evasion and reinstating normal hematopoietic processes., QC 20240715

Sammanfattning Vår studie handlar om matematik i förskolan, där vi har utgått från två frågeställningar. Den första handlar om vilka metoder som förskollärarna använder för att ge barnen en ökad kunskap för ett matematiskt lärande i ateljén. Den andra frågan handlar om vad förskollärarna har för syn på matematik i förskolan. I vår studie är syftet att synliggöra hur förskollärare undervisar om matematik i förskolan och i synnerhet i förskolans ateljé. Studien utgår från ett sociokulturellt perspektiv, där fokus ligger på kommunikation och samspel. Vår studie utgår från en kvalitativ metod där vi utför intervjuer med utbildade förskollärare. De deltagande respondenterna i studien arbetar på två olika förskolor i västra Sverige. Studiens resultat visar i likhet med tidigare forskning att ateljén förefaller främja barns lärande för matematik och det är viktigt att som pedagog stötta och vägleda barnen genom att vara en närvarand epedagog i barns utforskande och lärande av matematik., Summary Our study is about mathematics in preschool, where we have started from two issues. The first issue is about the methods that preschool teachers use to give children increased knowledge of mathematics in the art studio. The second question is about what view preschool teachers have of mathematics in preschool. The aim of the study is to make visible how preschoolteachers teach mathematics in preschool and especially in the art studio. The study is based ona socio-cultural perspective, where the focus is on communication and interaction. Our study is based on a qualitative method where we conducted interviews with preschool teachers. The participating respondents in the study work at two different preschools in the western part of Sweden. The results of the study show, like previous research, that the art studio promotes children's learning of mathematics, and how important it is that preschool teachers give support to children by being present while children explore and learn mathematics

Extracellular vesicles (EVs) are mediators of intercellular communication and a promising class of biomarkers. Surface proteins of EVs play decisive roles in establishing a connection with recipient cells, and they are putative targets for diagnostic assays. Analysis of the surface proteins can thus both illuminate the biological functions of EVs and help identify potential biomarkers. We developed a strategy combining high-resolution mass spectrometry (HRMS) and proximity ligation assays (PLA) to first identify and then validate surface proteins discovered on EVs. We applied our workflow to investigate surface proteins of small EVs found in seminal fluid (SF-sEV). We identified 1,014 surface proteins and verified the presence of a subset of these on the surface of SF-sEVs. Our work demonstrates a general strategy for deep analysis of EVs' surface proteins across patients and pathological conditions, proceeding from unbiased screening by HRMS to ultra-sensitive targeted analyses via PLA.

Extracellular vesicles (EVs) are increasingly tested as therapeutic vehicles and biomarkers, but still EV subtypes are not fully characterised. To isolate EVs with few co-isolated entities, a combination of methods is needed. However, this is time-consuming and requires large sample volumes, often not feasible in most clinical studies or in studies where small sample volumes are available. Therefore, we compared EVs rendered by five commonly used methods based on different principles from conditioned cell medium and 250 mu l or 3 ml plasma, that is, precipitation (ExoQuick ULTRA), membrane affinity (exoEasy Maxi Kit), size-exclusion chromatography (qEVoriginal), iodixanol gradient (OptiPrep), and phosphatidylserine affinity (MagCapture). EVs were characterised by electron microscopy, Nanoparticle Tracking Analysis, Bioanalyzer, flow cytometry, and LC-MS/MS. The different methods yielded samples of different morphology, particle size, and proteomic profile. For the conditioned medium, Izon 35 isolated the highest number of EV proteins followed by exoEasy, which also isolated fewer non-EV proteins. For the plasma samples, exoEasy isolated a high number of EV proteins and few non-EV proteins, while Izon 70 isolated the most EV proteins. We conclude that no method is perfect for all studies, rather, different methods are suited depending on sample type and interest in EV subtype, in addition to sample volume and budget.

Simple Summary Urinary bladder cancer (UBC) has a high recurrence rate, and biomarkers for different treatment strategies are highly needed. This study investigated the release of nanovesicles called exosomes from urinary bladder tissue from tumour-proximal sites as well as tumour-distant sites in transurethrally resected (TUR-B) patients with or without preoperative neoadjuvant chemotherapy prior to ensuing radical cystectomy-all without remaining visible tumour after TUR-B. We show that cancer-promoting exosomes were detected from both sites, suggesting that the previous tumour has altered the whole bladder tissue into a cancer-supporting milieu. The exosomes may originate from remaining pathologically undetectable cancer cells or transformed epithelial cells, and the study supports the notion of exosomes as mediators of metastatic spread and as potential biomarkers. It also supports early and radical removal of the bladder in urinary bladder cancer patients. Invasive urothelial bladder cancer (UBC) has high recurrence rates even after radical cystectomy (RC). Exosomes are membrane-bound nanovesicles, which have been shown to contribute to carcinogenesis and metastasis. We previously showed that urinary exosomes display a malignant profile in UBC patients despite the absence of detectable tumour. Here, we investigated exosomes from sampling sites close to or distant from the former tumour, aiming to understand the effect of the tumour on the local milieu. Ten patients scheduled for cystectomy after transurethral bladder resection (TUR-B), without remaining detectable tumour, were included. Exosomes were isolated from tissue explants of both the previous tumour site and distant bladder tissue. Proteins were quantified by mass spectrometry in seven patients. Exosomes from the previous tumour site were enriched in inflammatory but not cancer-related pathways compared to distant tissue. However, the 69 most abundant proteins in tissue-derived exosomes regardless of si