Now showing items 1-20 of 24

    • Bacteriomimetic Liposomes Improve Antibiotic Activity of a Novel Energy-Coupling Factor Transporter Inhibitor.

      Drost, Menka; Diamanti, Eleonora; Fuhrmann, Kathrin; Goes, Adriely; Shams, Atanaz; Haupenthal, Jörg; Koch, Marcus; Hirsch, Anna K H; Fuhrmann, Gregor; HIRI, Helmholtz-Institut für RNA-basierte Infektionsforschung, Josef-Shneider Strasse 2, 97080 Würzburg, Germany. (MDPI, 2021-12-21)
      Liposomes have been studied for decades as nanoparticulate drug delivery systems for cytostatics, and more recently, for antibiotics. Such nanoantibiotics show improved antibacterial efficacy compared to the free drug and can be effective despite bacterial recalcitrance. In this work, we present a loading method of bacteriomimetic liposomes for a novel, hydrophobic compound (HIPS5031) inhibiting energy-coupling factor transporters (ECF transporters), an underexplored antimicrobial target. The liposomes were composed of DOPG (18:1 (Δ9-cis) phosphatidylglycerol) and CL (cardiolipin), resembling the cell membrane of Gram-positive Staphylococcus aureus and Streptococcus pneumoniae, and enriched with cholesterol (Chol). The size and polydispersity of the DOPG/CL/± Chol liposomes remained stable over 8 weeks when stored at 4 °C. Loading of the ECF transporter inhibitor was achieved by thin film hydration and led to a high encapsulation efficiency of 33.19% ± 9.5% into the DOPG/CL/Chol liposomes compared to the phosphatidylcholine liposomes (DMPC/DPPC). Bacterial growth inhibition assays on the model organism Bacillus subtilis revealed liposomal HIPS5031 as superior to the free drug, showing a 3.5-fold reduction in CFU/mL at a concentration of 9.64 µM. Liposomal HIPS5031 was also shown to reduce B. subtilis biofilm. Our findings present an explorative basis for bacteriomimetic liposomes as a strategy against drug-resistant pathogens by surpassing the drug-formulation barriers of innovative, yet unfavorably hydrophobic, antibiotics.
    • Interaction of myxobacteria-derived outer membrane vesicles with biofilms: antiadhesive and antibacterial effects.

      Goes, Adriely; Vidakovic, Lucia; Drescher, Knut; Fuhrmann, Gregor; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany.; TWINCORE, Zentrum für experimentelle und klinische Infektionsforschung GmbH,Feodor-Lynen Str. 7, 30625 Hannover, Germany.; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Royal Society of Chemistry, 2021-08-02)
      Bacterial biofilms are widespread in nature and in medical settings and display a high tolerance to antibiotics and disinfectants. Extracellular vesicles have been increasingly studied to characterise their origins and assess their potential for use as a versatile drug delivery system; however, it remains unclear whether they also have antibiofilm effects. Outer membrane vesicles are lipid vesicles shed by Gram-negative bacteria and, in the case of myxobacteria, carry natural antimicrobial compounds produced by these microorganisms. In this study, we demonstrate that vesicles derived from the myxobacteria Cystobacter velatus Cbv34 and Cystobacter ferrugineus Cbfe23 are highly effective at inhibiting the formation and disrupting biofilms by different bacterial species.
    • Extracellular vesicles as a next-generation drug delivery platform.

      Herrmann, Inge Katrin; Wood, Matthew John Andrew; Fuhrmann, Gregor; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (Springer Nature, 2021-07-01)
      Extracellular-vesicle-based cell-to-cell communication is conserved across all kingdoms of life. There is compelling evidence that extracellular vesicles are involved in major (patho)physiological processes, including cellular homoeostasis, infection propagation, cancer development and cardiovascular diseases. Various studies suggest that extracellular vesicles have several advantages over conventional synthetic carriers, opening new frontiers for modern drug delivery. Despite extensive research, clinical translation of extracellular-vesicle-based therapies remains challenging. Here, we discuss the uniqueness of extracellular vesicles along with critical design and development steps required to utilize their full potential as drug carriers, including loading methods, in-depth characterization and large-scale manufacturing. We compare the prospects of extracellular vesicles with those of the well established liposomes and provide guidelines to direct the process of developing vesicle-based drug delivery systems.
    • Approaches to surface engineering of extracellular vesicles.

      Richter, Maximilian; Vader, Pieter; Fuhrmann, Gregor; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (Elsevier, 2021-04-06)
      Extracellular vesicles (EVs) are cell-derived nanoparticles that are important mediators in intercellular communication. This function makes them auspicious candidates for therapeutic and drug-delivery applications. Among EVs, mammalian cell derived EVs and outer membrane vesicles (OMVs) produced by gram-negative bacteria are the most investigated candidates for pharmaceutical applications. To further optimize their performance and to utilize their natural abilities, researchers have strived to equip EVs with new moieties on their surface while preserving the integrity of the vesicles. The aim of this review is to give a comprehensive overview of techniques that can be used to introduce these moieties to the vesicle surface. Approaches can be classified in regards to whether they take place before or after the isolation of EVs. The producing cells can be subjected to genetic manipulation or metabolic engineering to produce surface modified vesicles or EVs are engineered after their isolation by physical or chemical means. Here, the advantages and disadvantages of these processes and their applicability for the development of EVs as therapeutic agents are discussed.
    • Bacterial extracellular vesicles: Understanding biology promotes applications as nanopharmaceuticals.

      Jahromi, Leila Pourtalebi; Fuhrmann, Gregor; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (Elsevier, 2021-03-25)
      Extracellular vesicle (EV)-mediated communication between proximal and distant cells is a highly conserved characteristic in all of the life domains, including bacteria. These vesicles that contain a variety of biomolecules, such as proteins, lipids, nucleic acids, and small-molecule metabolites play a key role in the biology of bacteria. They are one of the key underlying mechanisms behind harmful or beneficial effects of many pathogenic, symbiont, and probiotic bacteria. These nanoscale EVs mediate extensive crosstalk with mammalian cells and deliver their cargos to the host. They are stable in physiological condition, can encapsulate diverse biomolecules and nanoparticles, and their surface could be engineered with available technologies. Based on favorable characteristics of bacterial vesicles, they can be harnessed for designing a diverse range of therapeutics and diagnostics for treatment of disorders including tumors and resistant infections. However, technical limitations for their production, purification, and characterization must be addressed in future studies.
    • Extracellular vesicles as antigen carriers for novel vaccination avenues.

      Mehanny, Mina; Lehr, Claus-Michael; Fuhrmann, Gregor; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (Elsevier, 2021-03-26)
      Antigen delivery has always been a challenge in scientific practice of vaccine formulation. Yet, mammalian extracellular vesicles (EVs) or bacterial membrane vesicles (MVs) provide an innovative avenue for safe and effective delivery of antigenic material. They include intrinsically loaded antigens from EV-secreting cells or extrinsically loaded antigens onto pre-formed vesicles. Interestingly, many studies shed light on potential novel anti-cancer vaccination immunotherapy for therapeutic applications from mammalian cell host-derived EVs, as well as conventional vaccination for prophylactic applications using bacterial cell-derived MVs against infectious diseases. Here, we discuss the rationale, status quo and potential for both vaccine applications using EVs.
    • Editorial EJPB - Biobarriers 2018.

      Fuhrmann, Gregor; Loretz, Brigitta; Schneider-Daum, Nicole; Lehr, Claus-Michael; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (Elsevier, 2020-11-02)
      [No abstract available]
    • Editorial: Mechanisms of Prokaryotic Predation.

      Whitworth, David E; Jurkevitch, Edouard; Pérez, Juana; Fuhrmann, Gregor; Koval, Susan F; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (Frontiers, 2020-09-08)
      No abstract available]
    • Probiomimetics-Novel Lactobacillus-Mimicking Microparticles Show Anti-Inflammatory and Barrier-Protecting Effects in Gastrointestinal Models.

      Kuhn, Thomas; Koch, Marcus; Fuhrmann, Gregor; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (Wiley, 2020-09-03)
      There is a lack of efficient therapies to treat increasingly prevalent autoimmune diseases, such as inflammatory bowel disease and celiac disease. Membrane vesicles (MVs) isolated from probiotic bacteria have shown tremendous potential for treating intestinal inflammatory diseases. However, possible dilution effects and rapid elimination in the gastrointestinal tract may impair their application. A cell‐free and anti‐inflammatory therapeutic system—probiomimetics—based on MVs of probiotic bacteria (Lactobacillus casei and Lactobacillus plantarum) coupled to the surface of microparticles is developed. The MVs are isolated and characterized for size and protein content. MV morphology is determined using cryoelectron microscopy and is reported for the first time in this study. MVs are nontoxic against macrophage‐like dTHP‐1 and enterocyte‐like Caco‐2 cell lines. Subsequently, the MVs are coupled onto the surface of microparticles according to facile aldehyde‐group functionalization to obtain probiomimetics. A significant reduction in proinflammatory TNF‐α level (by 86%) is observed with probiomimetics but not with native MVs. Moreover, it is demonstrated that probiomimetics have the ability to ameliorate inflammation‐induced loss of intestinal barrier function, indicating their potential for further development into an anti‐inflammatory formulation. These engineered simple probiomimetics that elicit striking anti‐inflammatory effects are a key step toward therapeutic MV translation.
    • Biogenic and Biomimetic Carriers as Versatile Transporters To Treat Infections.

      Goes, Adriely; Fuhrmann, Gregor; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (American Chemical Society, 2018-03-29)
      Biogenic and biomimetic therapeutics are a relatively new class of systems that are of physiological origin and/or take advantage of natural pathways or aim at mimicking these to improve selective interaction with target tissue. The number of biogenic and bioengineered avenues for drug therapy and diagnostics has multiplied over the past years for many applications, indicating the high expectations associated with this biological route. Nevertheless, the use of "bio"-related approaches for treating or diagnosing infectious diseases is still rare. Given that infectious diseases, in particular bacterial resistances, are seriously on the rise, there is an urgent need to take advantage of biogenic and bioengineered systems to target these challenges. In this manuscript, we first give a definition of the various "bio" terms, including biogenic, biomimetic, bioinspired, and bioengineered and we highlight them using tangible applications in the field of infectious diseases. Our examples cover cell-derived systems, including bioengineered bacteria, virus-like particles, and different cell-mimetics. Moreover, we discuss natural and bioengineered particles such as extracellular vesicles from mammalian and bacterial sources and liposomes. A concluding section outlines the potential for biomaterial-related avenues to overcome challenges associated with difficult-to-treat infections. We critically discuss benefits and risks for these applications and give an outlook on the future of biogenic engineering.
    • Liver-derived extracellular vesicles: A cell by cell overview to isolation and characterization practices.

      Zivko, Cristina; Fuhrmann, Gregor; Luciani, Paola; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (Elsevier, 2020-02-19)
      BACKGROUND: Extracellular vesicles (EVs) are a diverse group of membrane-bound nanovesicles potentially released by every cell. With the liver's unique ensemble of cells and its fundamental physiological tasks, elucidating the role of EV-mediated hepatic cellular crosstalk and their role in different pathologies has been gaining the attention of many scientists. SCOPE OF REVIEW: The present review shifts the perspective into practice: we aim to critically discuss the methods used to purify and to biochemically analyse EVs from specific liver resident cells, including hepatocytes, hepatic stellate cells, cholangiocytes, liver sinusoidal endothelial cells, Kupffer cells, liver stem cells. The review offers a reference guide to current approaches. MAJOR CONCLUSIONS: Strategies for EV isolation and characterization are as varied as the research groups performing them. We present main advantages and disadvantages for the methods, highlighting common causes for concern, such as FBS handling, reporting of cell viability, EV yield and storage, differences in differential centrifugations, suboptimal method descriptions, and method transferability. We both looked at how adaptable the research between human and rodent cells in vitro is, and also assessed how well either of them translates to ex vivo settings. GENERAL SIGNIFICANCE: We reviewed methodological practices for the isolation and analysis of liver-derived EVs, making a cell type specific user guide that shows where to start, what has worked so far and to what extent. We critically discussed room for improvement, placing a particular focus on working towards a potential standardization of methods.
    • Streptococcal Extracellular Membrane Vesicles Are Rapidly Internalized by Immune Cells and Alter Their Cytokine Release.

      Mehanny, Mina; Koch, Marcus; Lehr, Claus-Michael; Fuhrmann, Gregor; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (Frontiers, 2020-02-14)
      Extracellular vesicles are membranous structures shed by almost every living cell. Bacterial gram-negative outer membrane vesicles (OMVs) and gram-positive membrane vesicles (MVs) play important roles in adaptation to the surrounding environment, cellular components' exchange, transfer of antigens and virulence factors, and infection propagation. Streptococcus pneumoniae is considered one of the priority pathogens, with a global health impact due to the increase in infection burden and growing antibiotic resistance. We isolated MVs produced from the S. pneumoniae reference strain (R6) and purified them via size exclusion chromatography (SEC) to remove soluble protein impurities. We characterized the isolated MVs by nanoparticle tracking analysis (NTA) and measured their particle size distribution and concentration. Isolated MVs showed a mean particle size range of 130-160 nm and a particle yield of around 1012 particles per milliliter. Cryogenic transmission electron microscopy (cryo-TEM) images revealed a very heterogeneous nature of isolated MVs with a broad size range and various morphologies, arrangements, and contents. We incubated streptococcal MVs with several mammalian somatic cells, namely, human lung epithelial A549 and human keratinocytes HaCaT cell lines, and immune cells including differentiated macrophage-like dTHP-1 and murine dendritic DC2.4 cell lines. All cell lines displayed excellent viability profile and negligible cytotoxicity after 24-h incubation with MVs at concentrations reaching 106 MVs per cell (somatic cells) and 105 MVs per cell (immune cells). We evaluated the uptake of fluorescently labeled MVs into these four cell lines, using flow cytometry and confocal microscopy. Dendritic cells demonstrated prompt uptake after 30-min incubation, whereas other cell lines showed increasing uptake after 2-h incubation and almost complete colocalization/internalization of MVs after only 4-h incubation. We assessed the influence of streptococcal MVs on antigen-presenting cells, e.g., dendritic cells, using enzyme-linked immunosorbent assay (ELISA) and observed enhanced release of tumor necrosis factor (TNF)-α, a slight increase of interleukin (IL)-10 secretion, and no detectable effect on IL-12. Our study provides a better understanding of gram-positive streptococcal MVs and shows their potential to elicit a protective immune response. Therefore, they could offer an innovative avenue for safe and effective cell-free vaccination against pneumococcal infections.
    • Diffusion and transport of extracellular vesicles.

      Fuhrmann, Gregor; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (Springer Nature, 2020-02-17)
      Cell-derived extracellular vesicles are important intercellular communicators involved in many biological processes and diseases, including cancer and cardiovascular diseases, but, thus far, how they navigate within complex extracellular matrices has been poorly understood.
    • Coupling quaternary ammonium surfactants to the surface of liposomes improves both antibacterial efficacy and host cell biocompatibility

      Montefusco-Pereira, Carlos V.; Formicola, Beatrice; Goes, Adriely; Re, Francesca; Marrano, Claudia A.; Mantegazza, Francesco; Carvalho-Wodarz, Cristiane; Fuhrmann, Gregor; Caneva, Enrico; Nicotra, Francesco; et al. (Elsevier BV, 2020-04)
      By functionalizing the surface of PEG-liposomes with linkers bearing quaternary ammonium compounds (QACs), we generated novel bacteria disruptors with anti-adhesive properties and reduced cytotoxicity compared to free QACs. Furthermore, QAC-functionalized liposomes are a promising platform for future drug encapsulation. The QAC (11-mercaptoundecyl)-N,N,N-trimethylammonium bromide (MTAB) was attached to maleimide-functionalized liposomes (DSPE-PEG) via thiol linker. The MTAB-functionalized liposomes were physicochemically characterized and their biological activity, in terms of anti-adherence activity and biofilm prevention in Escherichia coli were assessed. The results showed that MTAB-functionalized liposomes inhibit bacterial adherence and biofilm formation while reducing MTAB toxicity.
    • Myxobacteria-Derived Outer Membrane Vesicles: Potential Applicability Against Intracellular Infections.

      Goes, Adriely; Lapuhs, Philipp; Kuhn, Thomas; Schulz, Eilien; Richter, Robert; Panter, Fabian; Dahlem, Charlotte; Koch, Marcus; Garcia, Ronald; Kiemer, Alexandra K; et al. (MDPI, 2020-01-12)
      In 2019, it was estimated that 2.5 million people die from lower tract respiratory infections annually. One of the main causes of these infections is Staphylococcus aureus, a bacterium that can invade and survive within mammalian cells. S. aureus intracellular infections are difficult to treat because several classes of antibiotics are unable to permeate through the cell wall and reach the pathogen. This condition increases the need for new therapeutic avenues, able to deliver antibiotics efficiently. In this work, we obtained outer membrane vesicles (OMVs) derived from the myxobacteria Cystobacter velatus strain Cbv34 and Cystobacter ferrugineus strain Cbfe23, that are naturally antimicrobial, to target intracellular infections, and investigated how they can affect the viability of epithelial and macrophage cell lines. We evaluated by cytometric bead array whether they induce the expression of proinflammatory cytokines in blood immune cells. Using confocal laser scanning microscopy and flow cytometry, we also investigated their interaction and uptake into mammalian cells. Finally, we studied the effect of OMVs on planktonic and intracellular S. aureus. We found that while Cbv34 OMVs were not cytotoxic to cells at any concentration tested, Cbfe23 OMVs affected the viability of macrophages, leading to a 50% decrease at a concentration of 125,000 OMVs/cell. We observed only little to moderate stimulation of release of TNF-alpha, IL-8, IL-6 and IL-1beta by both OMVs. Cbfe23 OMVs have better interaction with the cells than Cbv34 OMVs, being taken up faster by them, but both seem to remain mostly on the cell surface after 24 h of incubation. This, however, did not impair their bacteriostatic activity against intracellular S. aureus. In this study, we provide an important basis for implementing OMVs in the treatment of intracellular infections.
    • Toll-Like Receptor 2 Release by Macrophages: An Anti-inflammatory Program Induced by Glucocorticoids and Lipopolysaccharide.

      Hoppstädter, Jessica; Dembek, Anna; Linnenberger, Rebecca; Dahlem, Charlotte; Barghash, Ahmad; Fecher-Trost, Claudia; Fuhrmann, Gregor; Koch, Marcus; Kraegeloh, Annette; Huwer, Hanno; et al. (Frontiers, 2019-01-01)
      Glucocorticoids (GCs) are widely prescribed therapeutics for the treatment of inflammatory diseases, and endogenous GCs play a key role in immune regulation. Toll-like receptors (TLRs) enable innate immune cells, such as macrophages, to recognize a wide variety of microbial ligands, thereby promoting inflammation. The interaction of GCs with macrophages in the immunosuppressive resolution phase upon prolonged TLR activation is widely unknown. Treatment of human alveolar macrophages (AMs) with the synthetic GC dexamethasone (Dex) did not alter the expression of TLRs -1, -4, and -6. In contrast, TLR2 was upregulated in a GC receptor-dependent manner, as shown by Western blot and qPCR. Furthermore, long-term lipopolysaccharide (LPS) exposure mimicking immunosuppression in the resolution phase of inflammation synergistically increased Dex-mediated TLR2 upregulation. Analyses of publicly available datasets suggested that TLR2 is induced during the resolution phase of inflammatory diseases, i.e., under conditions associated with high endogenous GC production. TLR2 induction did not enhance TLR2 signaling, as indicated by reduced cytokine production after treatment with TLR2 ligands in Dex- and/or LPS-primed AMs. Thus, we hypothesized that the upregulated membrane-bound TLR2 might serve as a precursor for soluble TLR2 (sTLR2), known to antagonize TLR2-dependent cell actions. Supernatants of LPS/Dex-primed macrophages contained sTLR2, as demonstrated by Western blot analysis. Activation of metalloproteinases resulted in enhanced sTLR2 shedding. Additionally, we detected full-length TLR2 and assumed that this might be due to the production of TLR2-containing extracellular vesicles (EVs). EVs from macrophage supernatants were isolated by sequential centrifugation. Both untreated and LPS/Dex-treated cells produced vesicles of various sizes and shapes, as shown by cryo-transmission electron microscopy. These vesicles were identified as the source of full-length TLR2 in macrophage supernatants by Western blot and mass spectrometry. Flow cytometric analysis indicated that TLR2-containing EVs were able to bind the TLR2 ligand Pam3CSK4. In addition, the presence of EVs reduced inflammatory responses in Pam3CSK4-treated endothelial cells and HEK Dual reporter cells, demonstrating that TLR2-EVs can act as decoy receptors. In summary, our data show that sTLR2 and full-length TLR2 are released by macrophages under anti-inflammatory conditions, which may contribute to GC-induced immunosuppression.
    • Hot EVs - how temperature affects extracellular vesicles.

      Schulz, Eilien; Karagianni, Anna; Koch, Marcus; Fuhrmann, Gregor; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (Elsevier, 2019-12-02)
      In recent years, extracellular vesicles (EVs) and outer membrane vesicles (OMVs) have become an extensive and diverse field of research. They hold potential as diagnostic markers, therapeutics and for fundamental biological understanding. Despite ongoing studies, numerous information regarding function, content and stability of EVs remains unclear. If EVs and OMVs ought to be used as therapeutics and in clinical environments, their stability is one of the most important factors to be considered. Especially for formulation development, EVs and OMVs need to be stable at higher temperatures. To the best of our knowledge, very little work has been published regarding heat stability of neither EVs nor OMVs. In the present study, we investigated B lymphoblastoid cell-derived EVs and OMVs derived from myxobacterial species Sorangiineae as model vesicles. We exposed the vesicles to 37 °C, 50 °C, 70 °C and 100 °C for 1 h, 6 h and 24 h, and also autoclaved them. Interestingly, physico-chemical analyses such as size, particle concentration and protein concentration showed minor alterations, particularly at 37 °C. Flow cytometry analysis emphasised these results suggesting that after heat impact, EVs and OMVs were still able to be taken up by macrophage-like dTHP-1 cells. These data indicate that both mammalian and bacterial vesicles show intrinsic stability at physiological temperature. Our findings are important to consider for vesicle formulation and for advanced bioengineering approaches.
    • Extracellular Vesicles-Connecting Kingdoms.

      Woith, Eric; Fuhrmann, Gregor; Melzig, Matthias F; HIPS, Helmholtz-Institut für Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (MDPI, 2019-11-14)
      It is known that extracellular vesicles (EVs) are shed from cells of almost every type of cell or organism, showing their ubiquity in all empires of life. EVs are defined as naturally released particles from cells, delimited by a lipid bilayer, and cannot replicate. These nano- to micrometer scaled spheres shuttle a set of bioactive molecules. EVs are of great interest as vehicles for drug targeting and in fundamental biological research, but in vitro culture of animal cells usually achieves only small yields. The exploration of other biological kingdoms promises comprehensive knowledge on EVs broadening the opportunities for basic understanding and therapeutic use. Thus, plants might be sustainable biofactories producing nontoxic and highly specific nanovectors, whereas bacterial and fungal EVs are promising vaccines for the prevention of infectious diseases. Importantly, EVs from different eukaryotic and prokaryotic kingdoms are involved in many processes including host-pathogen interactions, spreading of resistances, and plant diseases. More extensive knowledge of inter-species and interkingdom regulation could provide advantages for preventing and treating pests and pathogens. In this review, we present a comprehensive overview of EVs derived from eukaryota and prokaryota and we discuss how better understanding of their intercommunication role provides opportunities for both fundamental and applied biology.
    • Appraisal on the wound healing potential of Melaleuca alternifolia and Rosmarinus officinalis L. essential oil-loaded chitosan topical preparations.

      Labib, Rola M; Ayoub, Iriny M; Michel, Haidy E; Mehanny, Mina; Kamil, Verena; Hany, Meryl; Magdy, Mirette; Moataz, Aya; Maged, Boula; Mohamed, Ahmed; et al. (PLOS, 2019-01-01)
      The present study investigates the wound healing potential of three chitosan-based topical preparations loaded with either tea tree essential oil, rosemary essential oil or a mixture of both oils in vivo. Essential oils of M. alternifolia and R. officinalis were analyzed using GC/MS. Essential oil-loaded chitosan topical preparations were formulated. Wound healing potential was evaluated in vivo using an excision wound model in rats. GC/MS analysis of M. alternifolia and R. officinalis essential oils revealed richness in oxygenated monoterpenes, representing 51.06% and 69.61% of the total oil composition, respectively. Topical application of chitosan-based formulation loaded with a mixture of tea tree and rosemary oils resulted in a significant increase in wound contraction percentage compared to either group treated with individual essential oils and the untreated group. Histopathological examination revealed that topical application of tea tree and rosemary oil combination demonstrated complete re-epithelialization associated with activated hair follicles. The high percentage of oxygenated monoterpenes in both essential oils play an important role in the antioxidant and wound healing potential observed herein. Incorporation of tea tree and rosemary essential oils in chitosan-based preparations in appropriate combination could efficiently promote different stages of wound healing.
    • Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

      Théry, Clotilde; Witwer, Kenneth W; Aikawa, Elena; Alcaraz, Maria Jose; Anderson, Johnathon D; Andriantsitohaina, Ramaroson; Antoniou, Anna; Arab, Tanina; Archer, Fabienne; Atkin-Smith, Georgia K; et al.