scholarly journals Leishmania-infected macrophages release extracellular vesicles that can promote lesion development

2020 ◽  
Vol 3 (12) ◽  
pp. e202000742
Author(s):  
Anna Gioseffi ◽  
Tim Hamerly ◽  
Kha Van ◽  
Naixin Zhang ◽  
Rhoel R Dinglasan ◽  
...  

Leishmania donovani infection of macrophages results in quantitative and qualitative changes in the protein profile of extracellular vesicles (EVs) released by the infected host cells. We confirmed mass spectrometry results orthogonally by performing Western blots for several Leishmania-infected macrophage-enriched EVs (LieEVs) molecules. Several host cell proteins in LieEVs have been implicated in promoting vascular changes in other systems. We also identified 59 parasite-derived proteins in LieEVs, including a putative L. donovani homolog of mammalian vasohibins (LdVash), which in mammals promotes angiogenesis. We developed a transgenic parasite that expressed an endogenously tagged LdVash/mNeonGreen (mNG) and confirmed that LdVash/mNG is indeed expressed in infected macrophages and in LieEVs. We further observed that LieEVs induce endothelial cells to release angiogenesis promoting mediators including IL-8, G-CSF/CSF-3, and VEGF-A. In addition, LieEVs induce epithelial cell migration and tube formation by endothelial cells in surrogate angiogenesis assays. Taken together, these studies show that Leishmania infection alters the composition of EVs from infected cells and suggest that LieEVs may play a role in the promotion of vascularization of Leishmania infections.

2021 ◽  
Author(s):  
Satarupa Ganguly ◽  
Bartika Ghoshal ◽  
Ishani Banerji ◽  
Shreya Bhattacharjee ◽  
Sreemoyee Chakraborty ◽  
...  

AbstractLeishmania donovani, the causative agent of visceral leishmaniasis, infects and resides within tissue macrophage cells of the mammalian host. It is not clear how the parasite infected cells cross-talk with the non-infected cells in the infection niche to regulate the infection process. Interestingly, miRNAs, the regulatory small RNAs of the host, could get trafficked into and out of infected cells as part of extracellular vesicles to ensure exchange of the epigenetic signals and can regulate the expression of their target genes in both donor and recipient cells. Leishmania, for its survival in host macrophage, adopts a dual strategy to regulate the intercellular transport of host miRNAs. The parasite, by preventing mitochondrial function of the host cells, restricts the entry of liver cell derived miR-122 containing extracellular vesicles in infected macrophage to curtail the inflammatory response by miR-122. The parasite reciprocally upregulates the extracellular export of anti-inflammatory miR-146a from the infected cells. The exported miR-146a restricts miR-122 production in liver cells and polarizes neighbouring naïve macrophages to the M2 state. miR-146a upregulates IL-10 in neighbouring macrophages where miR-146a dominates the RNA binding and miRNA suppressor protein HuR to inhibit the expression of proinflammatory cytokine mRNAs having HuR-interacting AU-rich elements and polarized the recipient cells to M2 stage.Graphical AbstractKey FindingsLeishmania stops vesicular entry of inflammatory miR-122 in infected cells by causing mitochondrial depolarizationLeishmania secrets miR-146a from infected cells to stop miR-122 production in neighbouring hepatocytesmiR-146a containing vesicles secreted by infected cells stops inflammatory response in recipient naïve macrophagemiR-146 targets RNA binding protein HuR to stop inflammatory cytokine production


2021 ◽  
Vol 22 (9) ◽  
pp. 4823
Author(s):  
María Fernanda González ◽  
Paula Díaz ◽  
Alejandra Sandoval-Bórquez ◽  
Daniela Herrera ◽  
Andrew F. G. Quest

Extracellular vesicles (EVs) are cell-derived vesicles important in intercellular communication that play an essential role in host-pathogen interactions, spreading pathogen-derived as well as host-derived molecules during infection. Pathogens can induce changes in the composition of EVs derived from the infected cells and use them to manipulate their microenvironment and, for instance, modulate innate and adaptive inflammatory immune responses, both in a stimulatory or suppressive manner. Gastric cancer is one of the leading causes of cancer-related deaths worldwide and infection with Helicobacter pylori (H. pylori) is considered the main risk factor for developing this disease, which is characterized by a strong inflammatory component. EVs released by host cells infected with H. pylori contribute significantly to inflammation, and in doing so promote the development of disease. Additionally, H. pylori liberates vesicles, called outer membrane vesicles (H. pylori-OMVs), which contribute to atrophia and cell transformation in the gastric epithelium. In this review, the participation of both EVs from cells infected with H. pylori and H. pylori-OMVs associated with the development of gastric cancer will be discussed. By deciphering which functions of these external vesicles during H. pylori infection benefit the host or the pathogen, novel treatment strategies may become available to prevent disease.


2021 ◽  
Vol 9 (6) ◽  
pp. 1144
Author(s):  
Isabel Marcelino ◽  
Philippe Holzmuller ◽  
Ana Coelho ◽  
Gabriel Mazzucchelli ◽  
Bernard Fernandez ◽  
...  

The Rickettsiales Ehrlichia ruminantium, the causal agent of the fatal tick-borne disease Heartwater, induces severe damage to the vascular endothelium in ruminants. Nevertheless, E. ruminantium-induced pathobiology remains largely unknown. Our work paves the way for understanding this phenomenon by using quantitative proteomic analyses (2D-DIGE-MS/MS, 1DE-nanoLC-MS/MS and biotin-nanoUPLC-MS/MS) of host bovine aorta endothelial cells (BAE) during the in vitro bacterium intracellular replication cycle. We detect 265 bacterial proteins (including virulence factors), at all time-points of the E. ruminantium replication cycle, highlighting a dynamic bacterium–host interaction. We show that E. ruminantium infection modulates the expression of 433 host proteins: 98 being over-expressed, 161 under-expressed, 140 detected only in infected BAE cells and 34 exclusively detected in non-infected cells. Cystoscape integrated data analysis shows that these proteins lead to major changes in host cell immune responses, host cell metabolism and vesicle trafficking, with a clear involvement of inflammation-related proteins in this process. Our findings led to the first model of E. ruminantium infection in host cells in vitro, and we highlight potential biomarkers of E. ruminantium infection in endothelial cells (such as ROCK1, TMEM16K, Albumin and PTPN1), which may be important to further combat Heartwater, namely by developing non-antibiotic-based strategies.


2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Asif Pathan ◽  
Talha Farid ◽  
Abdur Rahman Khan ◽  
Marjan Nasr ◽  
Marcin Wysoczynski ◽  
...  

Cell-based therapy is considered a promising approach to treat the damaged heart due to myocardial infarction. Although the mechanisms for their beneficial action are not yet clear, exosome/extracellular vesicles (EVs) secreted by these cells may be involved in their reparative paracrine signaling. Previous studies have suggested that EVs isolated from several cell types (e.g. cardiosphere-derived cells, embryonic stem cell, CD34+ stem cells) induce angiogenic activity both in vitro and in vivo . Here, we investigated whether EVs secreted by adult human cardiac mesenchymal cells (hCMCs) exhibit pro-angiogenic activity, and if so, what signaling molecules are involved in this process. hCMCs were isolated from right atrial appendage of patients undergoing cardiac procedures and were characterized by the expression of classical mesenchymal markers- CD29 (99.1%), CD73 (99.0%), CD90 (20.4%), CD105 (99.3%), CD 31 (16.8%), CD34 (0.9%) and CD45 (0.1%). EVs isolated from serum-free 24-hour hCMC conditioned media using PEG4000-based precipitation technique exhibited two distinct population of particles with size range of 10-60nm and 100-500nm in diameter; expressed characteristic exosomal markers- CD63, HSP70, Flotillin-1 and were negative for cellular organelle markers- calreticulin (ER and apoptotic bodies), prohibitin (mitochondria), GM130 (Golgi), Lamin B (nuclear protein), β-actin (cytoskeleton) and PMP70 (peroxisomes) as determined by immunoblotting. In vitro assays revealed that hCMC EVs promote human umbilical cord endothelial cells (HUVECs) proliferation, transwell migration in Boyden chamber and tube formation on Matrigel, indicative of enhanced angiogenesis. Angiogenic proteomic array identified that angiopoietin-1 (ANG-1) and angiopoietin-2 (ANG-2) proteins are highly enriched in EVs secreted by hCMCs. Furthermore, hCMC EV mediated HUVEC migration and tube formation was inhibited by TIE2 kinase inhibitor. Overall, these findings suggest that ANG-1 and ANG-2 are the key component of hCMC secreted EVs and they promote angiogenesis by activating TIE2 receptor in endothelial cells.


2019 ◽  
Vol 20 (24) ◽  
pp. 6363 ◽  
Author(s):  
Christien Madlen Beez ◽  
Maria Schneider ◽  
Marion Haag ◽  
Kathleen Pappritz ◽  
Sophie Van Linthout ◽  
...  

Cells release extracellular vesicles (EVs) to communicate in a paracrine manner with other cells, and thereby influence processes, such as angiogenesis. The conditioned medium of human cardiac-derived adherent proliferating (CardAP) cells was recently shown to enhance angiogenesis. To elucidate whether their released EVs are involved, we isolated them by differential centrifugation from the conditioned medium derived either in the presence or absence of a pro-inflammatory cytokine cocktail. Murine recipient cells internalized CardAP-EVs as determined by an intracellular detection of human proteins, such as CD63, by a novel flow cytometry method for studying EV–cell interaction. Moreover, endothelial cells treated for 24 h with either unstimulated or cytokine stimulated CardAP-EVs exhibited a higher tube formation capability on Matrigel. Interestingly, unstimulated CardAP-EVs caused endothelial cells to release significantly more vascular endothelial growth factor and interleukin (IL)-6, while cytokine stimulated CardAP-EVs significantly enhanced the release of IL-6 and IL-8. By nCounter® miRNA expression assay (NanoString Technologies) we identified microRNA 302d-3p to be enhanced in unstimulated CardAP-EVs compared to their cytokine stimulated counterparts, which was verified by quantitative polymerase chain reaction. This study demonstrates that both CardAP-EVs are pro-angiogenic by inducing different factors from endothelial cells. This would allow to select potent targets for a safe and efficient therapeutic application.


2015 ◽  
Vol 90 (2) ◽  
pp. 873-886 ◽  
Author(s):  
Jesus A. Silvas ◽  
Vsevolod L. Popov ◽  
Adriana Paulucci-Holthauzen ◽  
Patricia V. Aguilar

ABSTRACTSevere fever with thrombocytopenia syndrome (SFTS) virus is a newly recognized member of the genusPhlebovirusin the familyBunyaviridae. The virus was isolated from patients presenting with hemorrhagic manifestations and an initial case fatality rate of 12 to 30% was reported. Due to the recent emergence of this pathogen, there is limited knowledge on the molecular virology of SFTS virus. Recently, we reported that the SFTS virus NSs protein inhibited the activation of the beta interferon (IFN-β) promoter. Furthermore, we also found that SFTS virus NSs relocalizes key components of the IFN response into NSs-induced cytoplasmic structures. Due to the important role these structures play during SFTS virus replication, we conducted live cell imaging studies to gain further insight into the role and trafficking of these cytoplasmic structures during virus infection. We found that some of the SFTS virus NSs-positive cytoplasmic structures were secreted to the extracellular space and endocytosed by neighboring cells. We also found that these secreted structures isolated from NSs-expressing cells and SFTS virus-infected cells were positive for the viral protein NSs and the host protein CD63, a protein associated with extracellular vesicles. Electron microscopy studies also revealed that the isolated CD63-immunoprecipitated extracellular vesicles produced during SFTS virus infection contained virions. The virions harbored within these structures were efficiently delivered to uninfected cells and were able to sustain SFTS virus replication. Altogether, these results suggest that SFTS virus exploits extracellular vesicles to mediate virus receptor-independent transmission to host cells and open the avenue for novel therapeutic strategies against SFTS virus and related pathogens.IMPORTANCESFTS virus is novel bunyavirus associated with hemorrhagic fever illness. Currently, limited information is available about SFTS virus. In the present study, we demonstrated that extracellular vesicles produced by SFTS virus-infected cells harbor infectious virions. We sought to determine whether these “infectious” extracellular vesicles can mediate transmission of the virus and confirmed that the SFTS virions were efficiently transported by these secreted structures into uninfected cells and were able to sustain efficient replication of SFTS virus. These results have significant impact on our understanding of how the novel tick-borne phleboviruses hijack cellular machineries to establish infection and point toward a novel mechanism for virus replication among arthropod-borne viruses.


Oncotarget ◽  
2017 ◽  
Vol 8 (48) ◽  
pp. 83913-83924 ◽  
Author(s):  
James Lawson ◽  
Christopher Dickman ◽  
Sara MacLellan ◽  
Rebecca Towle ◽  
James Jabalee ◽  
...  

2017 ◽  
Vol 28 (15) ◽  
pp. 2091-2105 ◽  
Author(s):  
Yogaditya Chakrabarty ◽  
Suvendra N. Bhattacharyya

MicroRNAs (miRNAs), the tiny regulatory RNAs, form complexes with Argonaute (Ago) proteins and inhibit gene expression in metazoan cells. While studying parasite-invaded macrophages, we identify a unique mode of gene regulation in which the parasite Leishmania donovani (Ld) causes mitochondrial depolarization, reduces mitochondrial dynamics, and restricts turnover of cellular microRNA ribonucleoprotein (miRNP) complexes in infected host cells. This leads to increased stability of miRNPs along with elevated levels of Ago2-bound cytokine mRNA in Ld-infected macrophages. Thus the increase of miRNP stability in Ld-infected cells curtails production of proinflammatory cytokines, which are otherwise detrimental for survival of the parasite within the infected macrophages. Loss of mitochondrial membrane potential is accompanied by reduced juxtaposition of endoplasmic reticulum (ER) and mitochondria as well as endosomes. This is likely coupled with enhanced sequestration and stabilization of ER- associated miRNPs observed in infected macrophage cells. Mitofusin 2 (Mfn2), a membrane protein implicated in ER–mitochondria tethering, also shows reduced expression in Ld-infected cells. A mitochondrial role in Ld-induced alteration of miRNA activity and stability is further corroborated by impaired compartmentalization and stabilization of miRNP components in Mfn2-depleted mammalian cells.


2021 ◽  
pp. 0271678X2110079
Author(s):  
Jinghuan Fang ◽  
Michael Chopp ◽  
Hongqi Xin ◽  
Li Zhang ◽  
Fengjie Wang ◽  
...  

Plasminogen is involved in the process of angiogenesis; however, the underlying mechanism is unclear. Here, we investigated the potential contribution of plasmin/plasminogen in mediating angiogenesis and thereby contributing to functional recovery post-stroke. Wild-type plasminogen naive (Plg+/+) mice and plasminogen knockout (Plg−/−) mice were subjected to unilateral permanent middle cerebral artery occlusion (MCAo). Blood vessels were labeled with FITC-dextran. Functional outcomes, and cerebral vessel density were compared between Plg+/+ and Plg−/− mice at different time points after stroke. We found that Plg−/− mice exhibited significantly reduced functional recovery, associated with significantly decreased vessel density in the peri-infarct area in the ipsilesional cortex compared with Plg+/+ mice. In vitro, cerebral endothelial cells harvested from Plg−/− mice exhibited significantly reduced angiogenesis assessed using tube formation assay, and migration, as evaluated using Scratch assays, compared to endothelial cells harvested from Plg+/+ mice. In addition, using Western blots, expression of thrombospondin (TSP)-1 and TSP-2 were increased after MCAo in the Plg−/− group compared to Plg+/+ mice, especially in the ipsilesional side of brain. Taken together, our data suggest that plasmin/plasminogen down-regulates the expression level of TSP-1 and TSP-2, and thereby promotes angiogenesis in the peri-ischemic brain tissue, which contributes to functional recovery after ischemic stroke.


1998 ◽  
Vol 11 (9) ◽  
pp. 915-923 ◽  
Author(s):  
Preeti Dahiya ◽  
D. Janine Sherrier ◽  
Igor V. Kardailsky ◽  
Alexey Y. Borisov ◽  
Nicholas J. Brewin

The distribution of a lectinlike glycoprotein, PsNLEC-1, was examined with a specific antiserum in nodule tissue from a symbiotically defective pea mutant, Sprint2Fix¯(sym31), and the parent line, Sprint2. Immunostaining of Western blots (immunoblots) revealed that, whereas wild-type nodules contained three antigenic isoforms of PsNLEC-1, nodule homogenates of mutant sym31 contained only one isoform, PsNLEC-1C. Fractionation studies indicated that PsNLEC-1C was not associated with symbiosomes in either the mutant or the wild-type parent (unlike the other two isoforms from wild-type nodules). Light microscopy revealed that PsNLEC-1 antigen was more abundant in the infected tissues of wild-type nodules than in nodules of sym31. By contrast, in situ hybridization indicated that the PsNlec1 gene transcript was strongly expressed in infected cells of both Sprint2 and sym31 nodule tissues. At the ultrastructural level, most of the PsNLEC-1 antigen in sym31 nodule tissue was visualized as inclusion bodies in the vacuolar compartment of infected host cells but it was apparently absent from the symbiosome compartment. The results suggest an aberrant vesicle targeting pathway during symbiosome development in this mutant.


Sign in / Sign up

Export Citation Format

Share Document