Subpopulations of extracellular vesicles and their therapeutic potential

Lä,sser, Cecilia,Jang, Su Chul,Lö,tvall, Jan Elsevier 2018 Molecular aspects of medicine Vol.60 No.-

<P><B>Abstract</B></P> <P>Extracellular vesicles (EVs), such as exosomes and microvesicles, have over the last 10–15 years been recognized to convey key messages in the molecular communication between cells. Indeed, EVs have the capacity to shuttle proteins, lipids, and nucleotides such as RNA between cells, leading to an array of functional changes in the recipient cells. Importantly, the EV secretome changes significantly in diseased cells and under conditions of cellular stress. More recently, it has become evident that the EV secretome is exceptionally diverse, with many different types of EVs being released by a single cell type, and these EVs can be described in terms of differences in density, molecular cargos, and morphology. This review will discuss the diversity of EVs, will introduce some suggestions for how to categorize them, and will propose how EVs and their subpopulations might be used for very different therapeutic purposes.</P>

Two distinct extracellular RNA signatures released by a single cell type identified by microarray and next-generation sequencing

Lä,sser, Cecilia,Shelke, Ganesh Vilas,Yeri, Ashish,Kim, Dae-Kyum,Crescitelli, Rossella,Raimondo, Stefania,Sjö,strand, Margareta,Gho, Yong Song,Van Keuren Jensen, Kendall,Lö,tvall, Jan TaylorFrancis 2017 RNA BIOLOGY Vol.14 No.1

<P><B>ABSTRACT</B></P><P>Cells secrete extracellular RNA (exRNA) to their surrounding environment and exRNA has been found in many body fluids such as blood, breast milk and cerebrospinal fluid. However, there are conflicting results regarding the nature of exRNA. Here, we have separated 2 distinct exRNA profiles released by mast cells, here termed high-density (HD) and low-density (LD) exRNA. The exRNA in both fractions was characterized by microarray and next-generation sequencing. Both exRNA fractions contained mRNA and miRNA, and the mRNAs in the LD exRNA correlated closely with the cellular mRNA, whereas the HD mRNA did not. Furthermore, the HD exRNA was enriched in lincRNA, antisense RNA, vault RNA, snoRNA, and snRNA with little or no evidence of full-length 18S and 28S rRNA. The LD exRNA was enriched in mitochondrial rRNA, mitochondrial tRNA, tRNA, piRNA, Y RNA, and full-length 18S and 28S rRNA. The proteomes of the HD and LD exRNA-containing fractions were determined with LC-MS/MS and analyzed with Gene Ontology term finder, which showed that both proteomes were associated with the term extracellular vesicles and electron microscopy suggests that at least a part of the exRNA is associated with exosome-like extracellular vesicles. Additionally, the proteins in the HD fractions tended to be associated with the nucleus and ribosomes, whereas the LD fraction proteome tended to be associated with the mitochondrion.</P><P>We show that the 2 exRNA signatures released by a single cell type can be separated by floatation on a density gradient. These results show that cells can release multiple types of exRNA with substantial differences in RNA species content. This is important for any future studies determining the nature and function of exRNA released from different cells under different conditions.</P>

Detailed analysis of the plasma extracellular vesicle proteome after separation from lipoproteins

Karimi, Nasibeh,Cvjetkovic, Aleksander,Jang, Su Chul,Crescitelli, Rossella,Hosseinpour Feizi, Mohammad Ali,Nieuwland, Rienk,Lö,tvall, Jan,Lä,sser, Cecilia Springer International Publishing 2018 Cellular and Molecular Life Sciences Vol.75 No.15

<P>The isolation of extracellular vesicles (EVs) from blood is of great importance to understand the biological role of circulating EVs and to develop EVs as biomarkers of disease. Due to the concurrent presence of lipoprotein particles, however, blood is one of the most difficult body fluids to isolate EVs from. The aim of this study was to develop a robust method to isolate and characterise EVs from blood with minimal contamination by plasma proteins and lipoprotein particles. Plasma and serum were collected from healthy subjects, and EVs were isolated by size-exclusion chromatography (SEC), with most particles being present in fractions 8–12, while the bulk of the plasma proteins was present in fractions 11–28. Vesicle markers peaked in fractions 7–11; however, the same fractions also contained lipoprotein particles. The purity of EVs was improved by combining a density cushion with SEC to further separate lipoprotein particles from the vesicles, which reduced the contamination of lipoprotein particles by 100-fold. Using this novel isolation procedure, a total of 1187 proteins were identified in plasma EVs by mass spectrometry, of which several proteins are known as EV-associated proteins but have hitherto not been identified in the previous proteomic studies of plasma EVs. This study shows that SEC alone is unable to completely separate plasma EVs from lipoprotein particles. However, combining SEC with a density cushion significantly improved the separation of EVs from lipoproteins and allowed for a detailed analysis of the proteome of plasma EVs, thus making blood a viable source for EV biomarker discovery.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (10.1007/s00018-018-2773-4) contains supplementary material, which is available to authorized users.</P>

The Adverse Events and Hemodynamic Effects of Adenosine-Based Cardiac MRI

Thomas Voigtländer,Axel Schmermund,Peter Bramlage,Amelie Elsässer,Annett Magedanz,Hans-Ulrich Kauczor,Oliver K. Mohrs 대한영상의학회 2011 Korean Journal of Radiology Vol.12 No.4

Objective: We wanted to prospectively assess the adverse events and hemodynamic effects associated with an intravenous adenosine infusion in patients with suspected or known coronary artery disease and who were undergoing cardiac MRI. Materials and Methods: One hundred and sixty-eight patients (64 ± 9 years) received adenosine (140 μg/kg/min) during cardiac MRI. Before and during the administration, the heart rate, systemic blood pressure, and oxygen saturation were monitored using a MRI-compatible system. We documented any signs and symptoms of potential adverse events. Results: In total, 47 out of 168 patients (28%) experienced adverse effects, which were mostly mild or moderate. In 13 patients (8%), the adenosine infusion was discontinued due to intolerable dyspnea or chest pain. No high grade atrioventricular block, bronchospasm or other life-threatening adverse events occurred. The hemodynamic measurements showed a significant increase in the heart rate during adenosine infusion (69.3 ± 11.7 versus 82.4 ± 13.0 beats/min, respectively; p < 0.001). A significant but clinically irrelevant increase in oxygen saturation occurred during adenosine infusion (96 ± 1.9% versus 97 ± 1.3%, respectively; p < 0.001). The blood pressure did not significantly change during adenosine infusion (systolic: 142.8 ± 24.0 versus 140.9 ± 25.7 mmHg; diastolic: 80.2 ± 12.5 mmHg versus 78.9 ± 15.6, respectively). Conclusion: This study confirms the safety of adenosine infusion during cardiac MRI. A considerable proportion of all patients will experience minor adverse effects and some patients will not tolerate adenosine infusion. However, all adverse events can be successfully managed by a radiologist. The increased heart rate during adenosine infusion highlights the need to individually adjust the settings according to the patient, e.g., the number of slices of myocardial perfusion imaging. Objective: We wanted to prospectively assess the adverse events and hemodynamic effects associated with an intravenous adenosine infusion in patients with suspected or known coronary artery disease and who were undergoing cardiac MRI. Materials and Methods: One hundred and sixty-eight patients (64 ± 9 years) received adenosine (140 μg/kg/min) during cardiac MRI. Before and during the administration, the heart rate, systemic blood pressure, and oxygen saturation were monitored using a MRI-compatible system. We documented any signs and symptoms of potential adverse events. Results: In total, 47 out of 168 patients (28%) experienced adverse effects, which were mostly mild or moderate. In 13 patients (8%), the adenosine infusion was discontinued due to intolerable dyspnea or chest pain. No high grade atrioventricular block, bronchospasm or other life-threatening adverse events occurred. The hemodynamic measurements showed a significant increase in the heart rate during adenosine infusion (69.3 ± 11.7 versus 82.4 ± 13.0 beats/min, respectively; p < 0.001). A significant but clinically irrelevant increase in oxygen saturation occurred during adenosine infusion (96 ± 1.9% versus 97 ± 1.3%, respectively; p < 0.001). The blood pressure did not significantly change during adenosine infusion (systolic: 142.8 ± 24.0 versus 140.9 ± 25.7 mmHg; diastolic: 80.2 ± 12.5 mmHg versus 78.9 ± 15.6, respectively). Conclusion: This study confirms the safety of adenosine infusion during cardiac MRI. A considerable proportion of all patients will experience minor adverse effects and some patients will not tolerate adenosine infusion. However, all adverse events can be successfully managed by a radiologist. The increased heart rate during adenosine infusion highlights the need to individually adjust the settings according to the patient, e.g., the number of slices of myocardial perfusion imaging.