Polyacrylate adsorbents for the selective adsorption of cholesterol-rich lipoproteins from plasma or blood

Polyacrylate (PAA) adsorbents selectively bind low density lipoproteins (LDL) from human plasma and blood, whereas very low density lipoproteins (VLDL) are only minimally adsorbed. The adsorption of cholesterol-rich lipoproteins to PAA adsorbents is related to the molecular weight (mw) of the polyanion ligand. Ca++ and Mg++ inhibit the binding of LDL to PAA adsorbents. The chemical composition of the organic hardgels of the adsorbents does not have an influence on adsorption. The selective adsorption of LDL to PAA adsorbents can be explained to result from their low negative surface charge density and the specific colloid-chemical properties of the surface-bound PAA, which do not prevent LDL from binding to charge-like domains of the ligand. By contrast, VLDL and high density lipoproteins (HDL) are repelled from the adsorbents due to their higher negative surface charge density

Emerging roles of extracellular vesicle-associated non-coding RNAs in hypoxia: Insights from cancer, myocardial infarction and ischemic stroke

Hypoxia is a central pathophysiological component in cancer, myocardial infarction and ischemic stroke, which represent the most common medical conditions resulting in long-term disability and death. Recent evidence suggests common signaling pathways in these diverse settings mediated by non-coding RNAs (ncRNAs), which are packaged in extracellular vesicles (EVs) protecting ncRNAs from degradation. EVs are a heterogeneous group of lipid bilayer-covered vesicles released from virtually all cells, which have important roles in intercellular communication. Recent studies pointed out that ncRNAs including long non-coding RNAs (IncRNAs) and microRNAs (miRNAs) are selectively sorted into EVs, modulating specific aspects of cancer development, namely cell proliferation, migration, invasion, angiogenesis, immune tolerance or drug resistance, under conditions of hypoxia in recipient cells. In myocardial infarction and stroke, ncRNAs shuttled via EVs have been shown to control tissue survival and remodeling post-hypoxia by regulating cell injury, inflammatory responses, angiogenesis, neurogenesis or neuronal plasticity. This review discusses recent evidence on EV-associated ncRNAs in hypoxic cancer, myocardial infarction and stroke, discussing their cellular origin, biological function and disease significance. The emerging concept of IncRNA-circular RNA/ miRNA/ mRNA networks is outlined, upon which ncRNAs synergistically respond to hypoxia in order to modify disease responses. Particular notion is given to ncRNAs participating in at least two of the three conditions, which revealed a large degree of overlaps across pathophysiological conditions. Possible roles of EV-ncRNAs as therapeutic products or theranostic markers are defined

EV products obtained from iPSC-derived MSCs show batch-to-batch variations in their ability to modulate allogeneic immune responses in vitro

Mesenchymal stromal cells (MSCs) have demonstrated therapeutic potential in diverse clinical settings, largely due to their ability to produce extracellular vesicles (EVs). These EVs play a pivotal role in modulating immune responses, transforming pro-inflammatory cues into regulatory signals that foster a pro-regenerative milieu. Our previous studies identified the variability in the immunomodulatory effects of EVs sourced from primary human bone marrow MSCs as a consistent challenge. Given the limited proliferation of primary MSCs, protocols were advanced to derive MSCs from GMP-compliant induced pluripotent stem cells (iPSCs), producing iPSC-derived MSCs (iMSCs) that satisfied rigorous MSC criteria and exhibited enhanced expansion potential. Intriguingly, even though obtained iMSCs contained the potential to release immunomodulatory active EVs, the iMSC-EV products displayed batch-to-batch functional inconsistencies, mirroring those from bone marrow counterparts. We also discerned variances in EV-specific protein profiles among independent iMSC-EV preparations. Our results underscore that while iMSCs present an expansive growth advantage, they do not overcome the persistent challenge of functional variability of resulting MSC-EV products. Once more, our findings accentuate the crucial need for batch-to-batch functional testing, ensuring discrimination of effective and ineffective MSC-EV products for considered downstream applications

Flotillins Are Involved in the Polarization of Primitive and Mature Hematopoietic Cells

BACKGROUND: Migration of mature and immature leukocytes in response to chemokines is not only essential during inflammation and host defense, but also during development of the hematopoietic system. Many molecules implicated in migratory polarity show uniform cellular distribution under non-activated conditions, but acquire a polarized localization upon exposure to migratory cues. METHODOLOGY/PRINCIPAL FINDINGS: Here, we present evidence that raft-associated endocytic proteins (flotillins) are pre-assembled in lymphoid, myeloid and primitive hematopoietic cells and accumulate in the uropod during migration. Furthermore, flotillins display a polarized distribution during immunological synapse formation. Employing the membrane lipid-order sensitive probe Laurdan, we show that flotillin accumulation in the immunological synapse is concomittant with membrane ordering in these regions. CONCLUSIONS: Together with the observation that flotillin polarization does not occur in other polarized cell types such as polarized epithelial cells, our results suggest a specific role for flotillins in hematopoietic cell polarization. Based on our results, we propose that in hematopoietic cells, flotillins provide intrinsic cues that govern segregation of certain microdomain-associated molecules during immune cell polarization

Argumentationsanalyse von Kommentaren in einem Forum der BBC zur Unabhängigkeit des Kosovo

Die vorliegende Arbeit geht hervor aus dem Hauptseminar „Argumentationstheorie“, das im Wintersemester 2008/09 am Institut für Linguistik der Universität zu Köln unter der Leitung von PD Dr. Leila Behrens abgehalten wurde. Ziel dieses Seminars war es, ausgehend von traditionellen Begriffen der Rhetorik, Dialektik und Logik, in die Terminologie sowie in zentrale Modelle der zeitgenössischen Argumentationsforschung einzuführen. Die dabei erworbenen Kenntnisse sollen im Folgenden bei der Analyse von Beiträgen eines Diskussionsforums im Internet angewendet werden. Hierbei handelt es sich um ein sogenanntes „newsforum“ der BBC mit dem Titel „Have Your Say“ (BBC 2008), in dem aktuelle Themen und Nachrichten von Internetnutzern weltweit diskutiert werden können. Im untersuchten Fall behandeln wir die Frage, wie mit der Unabhängigkeitserklärung des Kosovo vom 17. Februar 2008 umzugehen sei: „Should the world recognise an independent Kosovo?“ […]. Zu dieser Fragestellung wurden insgesamt 3195 Beiträge im Forum veröffentlicht, von denen hier 780 ausgewertet werden. Diese folgen chronologisch aufeinander und umfassen den Zeitraum zwischen 7:49 Uhr (mittlere Greenwich-Zeit) und 14:26 Uhr des 17. Februar 2008

General consensus on multimodal functions and validation analysis of perinatal derivatives for regenerative medicine applications.

Perinatal tissues, such as placenta and umbilical cord contain a variety of somatic stem cell types, spanning from the largely used hematopoietic stem and progenitor cells to the most recently described broadly multipotent epithelial and stromal cells. As perinatal derivatives (PnD), several of these cell types and related products provide an interesting regenerative potential for a variety of diseases. Within COST SPRINT Action, we continue our review series, revising and summarizing the modalities of action and proposed medical approaches using PnD products: cells, secretome, extracellular vesicles, and decellularized tissues. Focusing on the brain, bone, skeletal muscle, heart, intestinal, liver, and lung pathologies, we discuss the importance of potency testing in validating PnD therapeutics, and critically evaluate the concept of PnD application in the field of tissue regeneration. Hereby we aim to shed light on the actual therapeutic properties of PnD, with an open eye for future clinical application. This review is part of a quadrinomial series on functional/potency assays for validation of PnD, spanning biological functions, such as immunomodulation, anti-microbial/anti-cancer, anti-inflammation, wound healing, angiogenesis, and regeneration

Methods and criteria for validating the multimodal functions of perinatal derivatives when used in oncological and antimicrobial applications

Perinatal derivatives or PnDs refer to tissues, cells and secretomes from perinatal, or birth-associated tissues. In the past 2 decades PnDs have been highly investigated for their multimodal mechanisms of action that have been exploited in various disease settings, including in different cancers and infections. Indeed, there is growing evidence that PnDs possess anticancer and antimicrobial activities, but an urgent issue that needs to be addressed is the reproducible evaluation of efficacy, both in vitro and in vivo. Herein we present the most commonly used functional assays for the assessment of antitumor and antimicrobial properties of PnDs, and we discuss their advantages and disadvantages in assessing the functionality. This review is part of a quadrinomial series on functional assays for the validation of PnDs spanning biological functions such as immunomodulation, anticancer and antimicrobial, wound healing, and regeneration

Perinatal derivatives: How to best characterize their multimodal functions in vitro. Part C: Inflammation, angiogenesis, and wound healing

Perinatal derivatives (PnD) are birth-associated tissues, such as placenta, umbilical cord, amniotic and chorionic membrane, and thereof-derived cells as well as secretomes. PnD play an increasing therapeutic role with beneficial effects on the treatment of various diseases. The aim of this review is to elucidate the modes of action of non-hematopoietic PnD on inflammation, angiogenesis and wound healing. We describe the source and type of PnD with a special focus on their effects on inflammation and immune response, on vascular function as well as on cutaneous and oral wound healing, which is a complex process that comprises hemostasis, inflammation, proliferation (including epithelialization, angiogenesis), and remodeling. We further evaluate the different in vitro assays currently used for assessing selected functional and therapeutic PnD properties. This review is a joint effort from the COST SPRINT Action (CA17116) with the intention to promote PnD into the clinics. It is part of a quadrinomial series on functional assays for validation of PnD, spanning biological functions, such as immunomodulation, anti-microbial/anti-cancer activities, anti-inflammation, wound healing, angiogenesis, and regeneration

Detailed Characterization of Small Extracellular Vesicles from Different Cell Types Based on Tetraspanin Composition by ExoView R100 Platform

Small extracellular vesicles (sEV) hold enormous potential as biomarkers, drug carriers, and therapeutic agents. However, due to previous limitations in the phenotypic characterization of sEV at the single vesicle level, knowledge of cell type-specific sEV signatures remains sparse. With the introduction of next-generation sEV analysis devices, such as the single-particle interferometric reflectance imaging sensor (SP-IRIS)-based ExoView R100 platform, single sEV analyses are now possible. While the tetraspanins CD9, CD63, and CD81 were generally considered pan-sEV markers, it became clear that sEV of different cell types contain several combinations and amounts of these proteins on their surfaces. To gain better insight into the complexity and heterogeneity of sEV, we used the ExoView R100 platform to analyze the CD9/CD63/CD81 phenotype of sEV released by different cell types at a single sEV level. We demonstrated that these surface markers are sufficient to distinguish cell-type-specific sEV phenotypes. Furthermore, we recognized that tetraspanin composition in some sEV populations does not follow a random pattern. Notably, the tetraspanin distribution of sEV derived from mesenchymal stem cells (MSCs) alters depending on cell culture conditions. Overall, our data provide an overview of the cell-specific characteristics of sEV populations, which will increase the understanding of sEV physiology and improve the development of new sEV-based therapeutic approaches