scholarly journals Phagocytosis-independent antimicrobial activity of mast cells by means of extracellular trap formation

Blood ◽  
2008 ◽  
Vol 111 (6) ◽  
pp. 3070-3080 ◽  
Author(s):  
Maren von Köckritz-Blickwede ◽  
Oliver Goldmann ◽  
Pontus Thulin ◽  
Katja Heinemann ◽  
Anna Norrby-Teglund ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Mast Cells ◽  
Immune Cell ◽  
Close Contact ◽  
Antimicrobial Effect ◽  
Immune Cell Population ◽  
Extracellular Traps ◽  
Dependent Cell ◽  
Critical Components ◽  
Extracellular Structures

AbstractThese days it has been increasingly recognized that mast cells (MCs) are critical components of host defense against pathogens. In this study, we have provided the first evidence that MCs can kill bacteria by entrapping them in extracellular structures similar to the extracellular traps described for neutrophils (NETs). We took advantage of the ability of MCs to kill the human pathogen Streptococcus pyogenes by a phagocytosis-independent mechanism in order to characterize the extracellular antimicrobial activity of MCs. Close contact of bacteria and MCs was required for full antimicrobial activity. Immunofluorescence and electron microscopy revealed that S pyogenes was entrapped by extracellular structures produced by MCs (MCETs), which are composed of DNA, histones, tryptase, and the antimicrobial peptide LL-37. Disruption of MCETs significantly reduced the antimicrobial effect of MCs, suggesting that intact extracellular webs are critical for effective inhibition of bacterial growth. Similar to NETs, production of MCETs was mediated by a reactive oxygen species (ROS)–dependent cell death mechanism accompanied by disruption of the nuclear envelope, which can be induced after stimulation of MCs with phorbol-12-myristate-13-acetate (PMA), H2O2, or bacterial pathogens. Our study provides the first experimental evidence of antimicrobial extracellular traps formation by an immune cell population other than neutrophils.

scholarly journals New Insights into the Antimicrobial Effect of Mast Cells against Enterococcus faecalis

2014 ◽  
Vol 82 (11) ◽  
pp. 4496-4507 ◽  
Author(s):  
Matthias Scheb-Wetzel ◽  
Manfred Rohde ◽  
Alicia Bravo ◽  
Oliver Goldmann
Keyword(s):  
Mast Cells ◽  
Enterococcus Faecalis ◽  
Bacterial Infections ◽  
Immune Cell ◽  
Hospital Setting ◽  
Antimicrobial Effect ◽  
Innate Immune ◽  
Immune Cell Population ◽  
Necrosis Factor Alpha ◽  
Content Type

ABSTRACTEnterococcus faecalishas emerged as an important cause of life-threatening multidrug-resistant bacterial infections in the hospital setting. The pathogenesis of enterococcal infections has remained a relatively neglected field despite their obvious clinical relevance. The objective of this study was to characterize the interactions between mast cells (MCs), an innate immune cell population abundant in the intestinal lamina propria, andE. faecalis. This study was conducted with primary bone marrow-derived murine MCs. The results demonstrated that MCs exerted an antimicrobial effect againstE. faecalisthat was mediated both by degranulation, with the concomitant discharge of the antimicrobial effectors contained in the granules, and by the release of extracellular traps, in whichE. faecaliswas snared and killed. In particular, the cathelicidin LL-37 released by the MCs had potent antimicrobial effect againstE. faecalis. We also investigated the specific receptors involved in the recognition ofE. faecalisby MCs. We found that Toll-like receptors (TLRs) are critically involved in the MC recognition ofE. faecalis, since MCs deficient in the expression of MyD88, an adaptor molecule required for signaling by most TLRs, were significantly impaired in their capacity to degranulate, to reduceE. faecalisgrowth as well as to release tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) after encountering this pathogen. Furthermore, TLR2 was identified as the most prominent TLR involved in the recognition ofE. faecalisby MCs. The results of this study indicate that MCs may be important contributors to the host innate immune defenses againstE. faecalis.

scholarly journals Parallel Aspects of the Microenvironment in Cancer and Autoimmune Disease

2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
Michal A. Rahat ◽  
Jivan Shakya
Keyword(s):  
Autoimmune Diseases ◽  
Immune Cell ◽  
Tissue Injury ◽  
Innate Immune ◽  
Immune Cell Population ◽  
Extracellular Traps ◽  
Pathological Conditions ◽  
Effector Cytokines ◽  
Self Antigen

Cancer and autoimmune diseases are fundamentally different pathological conditions. In cancer, the immune response is suppressed and unable to eradicate the transformed self-cells, while in autoimmune diseases it is hyperactivated against a self-antigen, leading to tissue injury. Yet, mechanistically, similarities in the triggering of the immune responses can be observed. In this review, we highlight some parallel aspects of the microenvironment in cancer and autoimmune diseases, especially hypoxia, and the role of macrophages, neutrophils, and their interaction. Macrophages, owing to their plastic mode of activation, can generate a pro- or antitumoral microenvironment. Similarly, in autoimmune diseases, macrophages tip the Th1/Th2 balance via various effector cytokines. The contribution of neutrophils, an additional plastic innate immune cell population, to the microenvironment and disease progression is recently gaining more prominence in both cancer and autoimmune diseases, as they can secrete cytokines, chemokines, and reactive oxygen species (ROS), as well as acquire an enhanced ability to produce neutrophil extracellular traps (NETs) that are now considered important initiators of autoimmune diseases. Understanding the contribution of macrophages and neutrophils to the cancerous or autoimmune microenvironment, as well as the role their interaction and cooperation play, may help identify new targets and improve therapeutic strategies.

scholarly journals A novel role for the transcription factor HIF-1α in the formation of mast cell extracellular traps

2012 ◽  
Vol 446 (1) ◽  
pp. 159-163 ◽  
Author(s):  
Katja Branitzki-Heinemann ◽  
Cheryl Y. Okumura ◽  
Lena Völlger ◽  
Yuko Kawakami ◽  
Toshiaki Kawakami ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Mast Cell ◽  
Hypoxia Inducible Factor ◽  
Transcriptional Regulator ◽  
Innate Immune ◽  
Immune Defence ◽  
Extracellular Traps ◽  
Innate Immune Defence ◽  
Critical Components ◽  
First Time

MCs (mast cells) are critical components of the host innate immune defence against bacterial pathogens, providing a variety of intra- and extra-cellular antimicrobial functions. In the present study we show, for the first time, that the transcriptional regulator HIF-1α (hypoxia-inducible factor-1α) mediates the extracellular antimicrobial activity of human and murine MCs by increasing the formation of MCETs (MC extracellular traps).

Evaluation of antimicrobial potential of some spices from apiaceae sold in herbal shops

2019 ◽  
Author(s):  
Alev ONDER ◽  
Suna Sibel GURPINAR, Mujde ERYILMAZ ◽  
Bayram Kagan AKAY, Ahsen Sevde CINAR
Keyword(s):  
Antimicrobial Activity ◽  
Daucus Carota ◽  
Antimicrobial Effect ◽  
Coriandrum Sativum ◽  
Apium Graveolens ◽  
Dilution Method ◽  
Anethum Graveolens ◽  
Foeniculum Vulgare ◽  
Pimpinella Anisum ◽  
Hexane Extracts

Spices are a part of the plants used for many purposes as preservatives and as colorants in foods or as medicinal intention. Main aim of the present research was to estimate the potential antimicrobial activity of some spices from Apiaceae family such as Amni visnaga (Diş otu, Hıltan), Anethum graveolens (Dereotu), Apium graveolens (Kereviz), Coriandrum sativum (Kişniş), Cuminum cyminum (Kimyon), Daucus carota (Havuç), Foeniculum vulgare (Rezene), Petroselinum sativum (Maydanoz), Pimpinella anisum (Anason). Thus, the fruits of the plants are used in the experiments. The fruits have been extracted by n-hexane, and all extracts have been subjected to TLC (Thin Layer Chromatography). The n-hexane extracts were screened for their potential in vitro antibacterial activity against Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 13883, Pseudomonas aeruginosa ATCC 27853 and antifungal activity against Candida albicans ATCC 10231 by microbroth dilution method. The hexane extracts of the fruits of Coriandrum sativum, Anethum graveolens, Daucus carota, and Pimpinella anisum did not show antimicrobial activity against tested microorganisms. Except these, the other extracts having MIC values of 2.5-5-10 mg/mL exhibited antimicrobial effect against some tested microorganisms. These results demonstrate that the extracts which have an antimicrobial effect can probably play a role as an antimicrobial agent owing to their nonpolar components which are accumulated to the n-hexane extracts.

scholarly journals Synergistic Antimicrobial Activities of Combinations of Vanillin and Essential Oils of Cinnamon Bark, Cinnamon Leaves and Cloves

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1406
Author(s):  
Rita Cava-Roda ◽  
Amaury Taboada-Rodríguez ◽  
Antonio López-Gómez ◽  
Ginés Benito Martínez-Hernández ◽  
Fulgencio Marín-Iniesta
Keyword(s):  
Antimicrobial Activity ◽  
Essential Oils ◽  
Food Packaging ◽  
Antimicrobial Effect ◽  
Antimicrobial Activities ◽  
Inhibitory Effects ◽  
Cinnamon Bark ◽  
E Coli ◽  
Pure Compounds ◽  
Main Component

Plant bioactive compounds have antimicrobial and antioxidant activities that allow them to be used as a substitute for synthetic chemical additives in both food and food packaging. To improve its sensory and bactericidal effects, its use in the form of effective combinations has emerged as an interesting possibility in the food industry. In this study, the antimicrobial activities of essential oils (EOs) of cinnamon bark, cinnamon leaves, and clove and the pure compounds vanillin, eugenol, and cinnamaldehyde were investigated individually and in combination against Listeria monocytogenes and Escherichia coli O157:H7. The possible interactions of combinations of pure compounds and EOs were performed by the two-dimensional checkerboard assay and isobologram methods. Vanillin exhibited the lowest antimicrobial activity (MIC of 3002 ppm against L. monocytogenes and 2795 ppm against E. coli O157:H7), while clove and cinnamon bark EOs exhibited the highest antimicrobial activity (402–404 against L. monocytogenes and 778–721 against E. coli O157:H7). For L. monocytogenes, pure compound eugenol, the main component of cinnamon leaves and clove, showed lower antimicrobial activity than EOs, which was attributed to the influence of the minor components of the EOs. The same was observed with cinnamaldehyde, the main component of cinnamon bark EO. The combinations of vanillin/clove EO and vanillin/cinnamon bark EO showed the most synergistic antimicrobial effect. The combination of the EOs of cinnamon bark/clove and cinnamon bark/cinnamon leaves showed additive effect against L. monocytogenes but indifferent effect against E. coli O157:H7. For L. monocytogenes, the best inhibitory effects were achieved by cinnamon bark EO (85 ppm)/vanillin (910 ppm) and clove EO (121 ppm)/vanillin (691 ppm) combinations. For E. coli, the inhibitory effects of clove EO (104 ppm)/vanillin (1006 ppm) and cinnamon leaves EO (118 ppm)/vanillin (979 ppm) combinations were noteworthy. Some of the tested combinations increased the antimicrobial effect and would allow the effective doses to be reduced, thereby offering possible new applications for food and active food packaging.

scholarly journals Novel Derivatives of 4-Methyl-1,2,3-Thiadiazole-5-Carboxylic Acid Hydrazide: Synthesis, Lipophilicity, and In Vitro Antimicrobial Activity Screening

2021 ◽  
Vol 11 (3) ◽  
pp. 1180
Author(s):  
Kinga Paruch ◽  
Łukasz Popiołek ◽  
Anna Biernasiuk ◽  
Anna Berecka-Rycerz ◽  
Anna Malm ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Carboxylic Acid ◽  
Bacterial Infections ◽  
Acid Hydrazide ◽  
Antimicrobial Effect ◽  
In Vitro Antimicrobial Activity ◽  
Research Goal ◽  
New Compounds ◽  
Derivatives Of

Bacterial infections, especially those caused by strains resistant to commonly used antibiotics and chemotherapeutics, are still a current threat to public health. Therefore, the search for new molecules with potential antimicrobial activity is an important research goal. In this article, we present the synthesis and evaluation of the in vitro antimicrobial activity of a series of 15 new derivatives of 4-methyl-1,2,3-thiadiazole-5-carboxylic acid. The potential antimicrobial effect of the new compounds was observed mainly against Gram-positive bacteria. Compound 15, with the 5-nitro-2-furoyl moiety, showed the highest bioactivity: minimum inhibitory concentration (MIC) = 1.95–15.62 µg/mL and minimum bactericidal concentration (MBC)/MIC = 1–4 µg/mL.

scholarly journals Antimicrobial Effect of Plasma-Activated Tap Water on Staphylococcus aureus, Escherichia coli, and Candida albicans

Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1480
Author(s):  
William Chiappim ◽  
Aline da Graça Sampaio ◽  
Felipe Miranda ◽  
Mariana Fraga ◽  
Gilberto Petraconi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Candida Albicans ◽  
Tap Water ◽  
Antimicrobial Effect ◽  
Gliding Arc ◽  
Oxidation Reduction ◽  
Treatment Conditions ◽  
Oxidation Reduction Potential

In this study, the potential antimicrobial activity of plasma-activated tap water (PAW) was evaluated against Staphylococcus aureus, Escherichia coli, and Candida albicans. For this, PAW was prepared in a gliding arc plasma system using two treatment conditions: stagnant water and water stirring by a magnetic stirrer, called moving water. Subsequently, their oxidation-reduction potential (ORP), pH, electrical conductivity (σ), and total dissolved solids (TDS) were monitored in different areas of the sample divided according to the depth of the beaker. It was observed that PAW obtained in dynamic conditions showed a more uniform acidity among the evaluated areas with pH 3.53 and ORP of 215 mV. Finally, standardized suspensions of Staphylococcus aureus (ATCC 6538), Escherichia coli (ATCC 10799), and Candida albicans (SC 5314) were treated with PAW, and the reduction of viable cells determined the antimicrobial effect. Our results indicate that the tap water, activated by plasma treatment using gliding arc, is an excellent inactivation agent in the case of Staphylococcus aureus and Escherichia coli. On the other hand, no significant antimicrobial activity was achieved for Candida albicans.

scholarly journals Neutrophil Extracellular Traps Serve as Key Effector Molecules in the Protection Against Phialophora verrucosa

2021 ◽  
Vol 186 (3) ◽  
pp. 367-375
Author(s):  
Qin Liu ◽  
Wenjuan Yi ◽  
Si Jiang ◽  
Jiquan Song ◽  
Pin Liang
Keyword(s):  
Neutrophil Extracellular Traps ◽  
Innate Immune ◽  
Immune Effector ◽  
Phialophora Verrucosa ◽  
Extracellular Traps ◽  
Sytox Green ◽  
Innate Immune Effector ◽  
Pathogen Control ◽  
Extracellular Structures

AbstractPhialophora verrucosa (P. verrucosa) is a pathogen that can cause chromoblastomycosis and phaeohyphomycosis. Recent evidence suggests that neutrophils can produce neutrophil extracellular traps (NETs) that can protect against invasive pathogens. As such, we herein explored the in vitro functional importance of P. verrucosa-induced NET formation. By assessing the co-localization of neutrophil elastase and DNA, we were able to confirm the formation of classical NETs entrapping P. verrucosa specimens. Sytox Green was then used to stain these NETs following neutrophil infection with P. verrucosa in order to quantify the formation of these extracellular structures. NET formation was induced upon neutrophil exposure to both live, UV-inactivated, and dead P. verrucosa fungi. The ability of these NETs to kill fungal hyphae and conidia was demonstrated through MTT and pouring plate assays, respectively. Overall, our results confirmed that P. verrucosa was able to trigger the production of NETs, suggesting that these extracellular structures may represent an important innate immune effector mechanism controlling physiological responses to P. verrucosa infection, thereby aiding in pathogen control during the acute phases of infection.

Sign in / Sign up

Export Citation Format

Share Document