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måndag 21 maj 2018

ESCRT-0 HRS omaa FYVE- PI-3-K motiivin .olisiko tässä kohta, johon on anti EBOV-lääke, Apilimod

 EBOV tarvitsee ehdottomasti  korkeampien organismien fosfoinositidilipidilaatuja virionin valmistukseen.  ja ilmeisesti muihinkin  vaiheisiin. 

Abstract
Phosphatidylinositol-3-phosphate 5-kinase (PIKfyve) is a lipid kinase involved in endosome maturation that emerged from a haploid genetic screen as being required for Ebola virus (EBOV) infection. Here we analyzed the effects of apilimod, a PIKfyve inhibitor that was reported to be well tolerated in humans in phase 2 clinical trials, for its effects on entry and infection of EBOV and Marburg virus (MARV). We first found that apilimod blocks infections by EBOV and MARV in Huh 7, Vero E6 and primary human macrophage cells, with notable potency in the macrophages (IC50, 10 nM). We next observed that similar doses of apilimod block EBOV-glycoprotein-virus like particle (VLP) entry and transcription-replication competent VLP infection, suggesting that the primary mode of action of apilimod is as an entry inhibitor, preventing release of the viral genome into the cytoplasm to initiate replication. After providing evidence that the anti-EBOV action of apilimod is via PIKfyve, we showed that it blocks trafficking of EBOV VLPs to endolysosomes containing Niemann-Pick C1 (NPC1), the intracellular receptor for EBOV. Concurrently apilimod caused VLPs to accumulate in early endosome antigen 1-positive endosomes. We did not detect any effects of apilimod on bulk endosome acidification, on the activity of cathepsins B and L, or on cholesterol export from endolysosomes. Hence by antagonizing PIKfyve, apilimod appears to block EBOV trafficking to its site of fusion and entry into the cytoplasm. Given the drug’s observed anti-filoviral activity, relatively unexplored mechanism of entry inhibition, and reported tolerability in humans, we propose that apilimod be further explored as part of a therapeutic regimen to treat filoviral infections.

The Phosphatidylinositol-3-phosphate... (PDF Download Available). Available from: https://www.researchgate.net/publication/316078827_The_Phosphatidylinositol-3-phosphate_5-kinase_inhibitor_Apilimod_blocks_filoviral_entry_and_infection?_sg=jHD1ro2wp8OvvZ9-i_RrU8KdUSjG5m95aksJdi4LV3XOz-A4q8nBzgYUjn6qoD1H02-d45KZOdtfy1ITq6T3aZSqqTtfOCKNlg [accessed May 21 2018].
Abstract
Phosphatidylinositol-3-phosphate 5-kinase (PIKfyve) is a lipid kinase involved in endosome maturation that emerged from a haploid genetic screen as being required for Ebola virus (EBOV) infection. Here we analyzed the effects of apilimod, a PIKfyve inhibitor that was reported to be well tolerated in humans in phase 2 clinical trials, for its effects on entry and infection of EBOV and Marburg virus (MARV).

We first found that apilimod blocks infections by EBOV and MARV in Huh 7, Vero E6 and primary human macrophage cells, with notable potency in the macrophages (IC50, 10 nM).

We next observed that similar doses of apilimod block EBOV-glycoprotein-virus like particle (VLP) entry and transcription-replication competent VLP infection, suggesting that the primary mode of action of apilimod is as an entry inhibitor, preventing release of the viral genome into the cytoplasm to initiate replication.

After providing evidence that the anti-EBOV action of apilimod is via PIKfyve, we showed that it blocks trafficking of EBOV VLPs to endolysosomes containing Niemann-Pick C1 (NPC1), the intracellular receptor for EBOV.

Concurrently apilimod caused VLPs to accumulate in early endosome antigen 1-positive endosomes.

We did not detect any effects of apilimod on bulk endosome acidification, on the activity of cathepsins B and L, or on cholesterol export from endolysosomes. Hence by antagonizing PIKfyve, apilimod appears to block EBOV trafficking to its site of fusion and entry into the cytoplasm.

Given the drug’s observed anti-filoviral activity, relatively unexplored mechanism of entry inhibition, and reported tolerability in humans, we propose that apilimod be further explored as part of a therapeutic regimen to treat filoviral infections.

The Phosphatidylinositol-3-phosphate... (PDF Download Available). Available from: https://www.researchgate.net/publication/316078827_The_Phosphatidylinositol-3-phosphate_5-kinase_inhibitor_Apilimod_blocks_filoviral_entry_and_infection?_sg=jHD1ro2wp8OvvZ9-i_RrU8KdUSjG5m95aksJdi4LV3XOz-A4q8nBzgYUjn6qoD1H02-d45KZOdtfy1ITq6T3aZSqqTtfOCKNlg [accessed May 21 2018].

Kts. ESCRT complex:  endosomaalisessa kalvosaa PIP3 ja ESCRT-0  kompleksin jäsen    Hrs, jolla on  FYVE- domeeni, joka kiinnittyy PI3P molekyyliin.
Bildresultat för hrs/vps27, ESCRT-0

https://openi.nlm.nih.gov/detailedresult.php?img=PMC2172707_200302136f7&req=4








Kongon Ebola, Mortaliteetti 56%, 26 kuollutta, näistä kolme terveysalan työntekijää; 45 varmaa tapausta

http://www.who.int/news-room/detail/18-05-2018-statement-on-the-1st-meeting-of-the-ihr-emergency-committee-regarding-the-ebola-outbreak-in-2018


tisdag 15 maj 2018

Kongon Ebolapurkauksen laajuutta hahmotetaan

https://www.vox.com/2018/5/11/17341430/ebola-outbreak-virus-democratic-republic-of-congo
Tähän mennessä kolme terveydenhoitohenkilökuntaan kuuluvaa on menehtynyt. 

ESCRT kompleksi rekrytoituu virusten virionien tehokkaaseen laukaisemiseen isäntäsolusta.

Olen katsomassa ESCRT kompleksin  proteiineja.

Favipiravir testattu Ebolavirusta vastaan

http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1002535
RSV infektionhoidossa on  aiemmn kombinoitu ribavir ja facipiravir suotuisasti.
Nyt on testattu favipiravir antivirustehoa Ebolavirusta vastaan.  Elossapysymisprosentti hieman nousi.
http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1002535
Muistiin 15.5. 2018

fredag 11 maj 2018

Eräs ihmisen E3-ubikitiiniligaasi rekrytoituu Ebolaviruksen tarpeisiin


https://www.ncbi.nlm.nih.gov/pubmed/28768865
Taustaa E3 ubikitiiniligaaseista, joita ihmisellä on luonnollisen immuunipuolustuksensa   arsenaalissa. 

  • RING-type E3 ligases
  1.  ( Single type, esim. Co-Cbl, MDM2, BRCA1. 
  2. RBR type (RING between RING)
  3. TRIM type( Näitä  on ainakin 1-76, joku sanoo että 82)
  4. Cullin type (SCF-type/VHL-type, BTB-type)
  5. APL/cyclocome 
  • RING type E3, U-box type E3 (CHIP, E4B, E4A..) 
  • HECT type E3
  1. CE6A8, Nedd 4, Smurf1/2...
  • Unclassified E3
  • TAF250, A20, IpaH family, Sde A ...

TRIM-tyyppisitä  olen kirjoitanut musitiin Solusykliblogiini, lähinnä onkologian kannalta.
nyt katson mitä tästä HECT-tyyppisestä  E3 ligaasista snotaan Ebolaviruksen kannalta.
 .............
LÄHDE: Viimesyksyinen artikkeli PubMed:ssä. UBIKITIINILIGAASI WWP1 tekee interaktion  Ebolavirusksen VP24 proteiinin kanssa ja näin säätyy virionien pääsy  solusta ulos.


J Virol. 2017 Sep 27;91(20). pii: e00812-17. doi: 10.1128/JVI.00812-17. Print 2017 Oct 15.

Ubiquitin Ligase WWP1 Interacts with Ebola Virus VP40 To Regulate Egress.


Abstract

Ebola virus (EBOV) is a member of the Filoviridae family and the cause of hemorrhagic fever outbreaks. The EBOV VP40 (eVP40) matrix protein is the main driving force for virion assembly and budding. Indeed, expression of eVP40 alone in mammalian cells results in the formation and budding of virus-like particles (VLPs) which mimic the budding process and morphology of authentic, infectious EBOV.

 To complete the budding process, eVP40 utilizes its PPXY L-domain motif to recruit a specific subset of host proteins containing one or more modular WW domains that then function to facilitate efficient production and release of eVP40 VLPs.

 In this report, we identified additional host WW-domain interactors by screening for potential interactions between mammalian proteins possessing one or more WW domains and WT or PPXY mutant peptides of eVP40.

We identified the HECT family E3 ubiquitin ligase WWP1 and all four of its WW domains as strong interactors with the PPXY motif of eVP40. The eVP40-WWP1 interaction was confirmed by both peptide pulldown and coimmunoprecipitation assays, which also demonstrated that modular WW domain 1 of WWP1 was most critical for binding to eVP40.

 Importantly, the eVP40-WWP1 interaction was found to be biologically relevant for VLP budding since
 (i) small interfering RNA (siRNA) knockdown of endogenous WWP1 resulted in inhibition of eVP40 VLP egress,
 (ii) coexpression of WWP1 and eVP40 resulted in ubiquitination of eVP40 and a subsequent increase in eVP40 VLP egress,
and (iii) an enzymatically inactive mutant of WWP1 (C890A) did not ubiquitinate eVP40 or enhance eVP40 VLP egress.

 Last, our data show that ubiquitination of eVP40 by WWP1 enhances egress of VLPs and concomitantly decreases cellular levels of higher-molecular-weight oligomers of eVP40.

In sum, these findings contribute to our fundamental understanding of the functional interplay between host E3 ligases, ubiquitination, and regulation of EBOV VP40-mediated egress.

IMPORTANCE Ebola virus (EBOV) is a high-priority, emerging human pathogen that can cause severe outbreaks of hemorrhagic fever with high mortality rates. As there are currently no approved vaccines or treatments for EBOV, a better understanding of the biology and functions of EBOV-host interactions that promote or inhibit viral budding is warranted.

Here, we describe a physical and functional interaction between EBOV VP40 (eVP40) and WWP1, a host E3 ubiquitin ligase that ubiquitinates VP40 and regulates VLP egress. This viral PPXY-host WW domain-mediated interaction represents a potential new target for host-oriented inhibitors of EBOV egress.

KEYWORDS:

E3 ubiquitin ligase; Ebola virus; L-domain; PPXY; VLPs; VP40; WW domain;
WWP1; https://www.ncbi.nlm.nih.gov/gene/11059
budding

HECT tyyppiset E3 ubikitiiniligaasit

Biol Chem. 2018 Jan 26;399(2):127-145. doi: 10.1515/hsz-2017-0184.

Structural mechanisms of HECT-type ubiquitin ligases.

Abstract

Ubiquitin ligases (E3 enzymes) transfer ubiquitin from ubiquitin-conjugating (E2) enzymes to target proteins. By determining the selection of target proteins, modification sites on those target proteins, and the types of ubiquitin modifications that are formed, E3 enzymes are key specificity factors in ubiquitin signaling. Here, I summarize our knowledge of the structural mechanisms in the HECT E3 subfamily, many members of which play important roles in human disease. I discuss interactions of the conserved HECT domain with E2 enzymes, ubiquitin and target proteins, as well as macromolecular interactions with regulatory functions. While we understand individual steps in the catalytic cycle of HECT E3 enzymes on a structural level, this review also highlights key aspects that have yet to be elucidated. For instance, it remains unclear how diverse target proteins are presented to the catalytic center and how certain HECT E3 enzymes achieve specificity in ubiquitin linkage formation. The structural and functional properties of the N-terminal regions of HECT E3 enzymes that likely act as signaling hubs are also largely unknown. Structural insights into these aspects may open up routes for a therapeutic intervention with specific HECT E3 functions in distinct pathophysiological settings.

KEYWORDS:E3 enzyme; X-ray crystallography; enzyme mechanism; enzyme regulation; posttranslational modification

PMID: 29016349 DOI: 10.1515/hsz-2017-0184
  • https://www.cell.com/molecular-cell/pdf/S1097-2765(17)30230-7.pdf
  •  
  • cGAS-STING tie signaloi DNA viruksista

    https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQ4dODS2WuegzsM-YWCzp2bFJud1R4OVNfHuxJRvs6i5mJ4HOdI


    Doxorubicin 
     https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3116111/


    DNA sensori tie, jos on DNA-virus.
    Tähän jräejstelmäänkuuluu luonnollsien immuniteetin TRIm21-proteiini, muta näin suoraa  cGAS--STING tien  aktivoimista ei tapahdu ebholassa käsittääkseni.
    Muistiin kuitenkin tämä asia:
    https://www.nature.com/articles/cmi201312
    Tässä ehkä on syt palata katsomaan TRIM21 kohtalo  EBOV viruksessa. Katsooko EBOV aiheelliseki  detonoida tämän  tekijän.
    Muistaakseni EBOV infektiossa kehittyy kova monosyyttiperäinen sytokiinimyrsky.

    • TRIM21 (RoSSA)  osallistuu kyllä monosyyttivaihteeseen jos on kapseloitunut , Ainakin HIV-1 viruksesta on aktsottu suhde TRIM21.een ja  TRIM21 pakkautuu virioniin mukaan.
     https://www.ncbi.nlm.nih.gov/pubmed/27773663/
    Otan sitaatin muistiin:

     Abstract
    Tripartite motif-containing protein 21 (TRIM21) play a dual role in the cytoplasm of the cells where it facilitates destruction of some antibody-coated viruses and some bacteria, and initiates synthesis of proinflammatory cytokines. Macrophages and CD16+ monocyte subset can particularly participate in a proinflammatory response caused by viral infection, however, the molecular mechanisms underlying these processes are not fully understood. The aim of this study was to determine the level of TRIM21-mRNA expression in monocyte subsets including: classical (CD14++CD16-), intermediate (CD14++CD16+) and non-classical (CD14+CD16++) monocytes, as well as during in vitro differentiation of the isolated monocytes towards dendritic cells or macrophages. Our results revealed that the level of TRIM21 mRNA expression was significantly lower in CD16- monocytes, when compared to CD16+ cells and the whole monocyte population, yet no significant differences were observed when CD16+ population was divided into intermediate and non-classical subsets. More pronounced differences were observed in the case of monocyte-derived macrophages (MDM) and dendritic cells (DCs). TRIM21-mRNA expression level was app. 6-fold higher in DCs, and app. 16-fold higher in MDM (p<0 by="" cd16="" compared="" cytokine="" freshly="" increased="" isolated="" may="" mechanism="" monocytes.="" new="" of="" our="" production="" proinflammatory="" results="" suggest="" sup="" the="" to="" when="">+
    (intermediate and non-classical) monocytes and macrophages, at least in patients with acute or chronic infections, caused by enveloped viruses. We suggest that TRIM21 may be one of the factors associated with the "switching on" the proinflammatory programme in CD16+ monocytes or monocyte-derived macrophages.
    Kuva
    Normaalisti toimia  DNA virus---- STING - TRIM  signalointi
    Bildresultat för cCAS-STING signaling pathway




    VLP rokotekehittelystä

    Tällä saatiin aikaan varhainen IFN 1 tyypin interferonin tuotanto. IFNAR- (reseptorin) olemassaolo on edellytys, että tämä  strategia vaikuttaa.

    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4342244/
     ---
     Virally encoded anti-IFN proteins, VP24 and VP35 play major roles in EBOV virulence [7, 8]. VP35 blocks type I IFN induction in dendritic cells (DCs) and macrophages, and acts as a virulence factor necessary for a recombinant virus to attain infectivity in the host [912]. VP24, on the other hand, blocks IFN signaling by interfering with IFN activated JAK/STAT pathways [7].
    ---
    VLPs are subunit-based vaccines, extensively studied for a variety of infectious pathogens [25, 26]. VLPs prepared from EBOV and other filoviruses are composed of the matrix protein (VP40), glycoprotein (GP), and at times nucleoprotein (NP) and represent a potentially promising candidate for EBOV vaccine.
    ----
     We next tested whether VLPs induce other ISGs, particularly those with negative regulatory activities. This question was of interest to us, since mice that did not receive VLPs expressed higher levels of proinflammatory cytokines and chemokines, which raised the possibility that IFN signaling exerts negative regulatory activity towards proinflammatory responses, perhaps by controlling NF-κB activation [36]. Shown in the lower panels in Fig. 2A and 2B is induction of IRGM1, USP18, TRIM21 and TRIM30. IRGM1 is an IFN inducible GTPase that inhibits LPS induced endotoxin shock in mice [37]. USP18 is an ISG15 deconjugating factor that negatively regulates TLR signaling and resultant cytokine induction [38]. Trim21 and Trim30 are members of the Tripartite motif family that downregulate TLR induced inflammatory responses [3942]. Expression of these ISGs was also higher in the VLP injected group than that without VLPs both in liver and spleen. Similar to anti-viral ISGs, expression of these negative regulatory factors changed at the later stage (S1 Fig). These data indicate that VLPs accelerate induction of anti-viral and negative regulatory ISGs, which may help suppress EBOV’s anti-IFN antagonism (See Discussion).



    Huom sekä TRIM30 että TRIm21  voivat puuttua interferonijärejstelmän kehkeyttämsien sekä cGAS-STING  signaalitiessä (joka havaitsee DNA.n)  että TLR- väliteisessä  patogeenin havaitsevassa signaalitiessä  ja tässä  VLP-rokotetapaukseesa kyse on vaikuttamisesta  TLR tietä  indusoidun  inflammatorisen vasteen  vaimentamisesta ( mikä on hyvin raju ja letaali EBOV-virusinfektiossa9.

     Sikäli on  hyvä että tämä  VPL rokote ei koostu DNA-materiaalista, joka ottaisi  mukaan mainitun cGAS- STING tien signaloinnin  tähän vaikeaan koktailiin.

    Yleis KUVA jossa IFNAR reseptori näkyy.
    Tämä kuvaa isäntäkehon varustuksia ja normaaleita  konvergoituvia signaaliteitä interferonijärjestelmässä, joka lopulta  antaa  diversiteetillä   interferonilla stimuloiduista geenistä(ISG)  antivirusvastetta solun asettuessa antivirusstatukseen.   On ymmärrettävää että evoluution aikana virukset ovat kehittäneet proteiineja jotka sofistisesti  lamaavat tämän järjestelmän.

    https://www.researchgate.net/figure/IFN-stimulated-gene-expression-via-the-JAK-STAT-signaling-pathways-Upon-recognition-of_fig1_23626519







    Ebolaviruksen mikroRNAkirjosta

    https://www.ncbi.nlm.nih.gov/pubmed/27094387

    Cell Mol Life Sci. 2016 Oct;73(19):3733-44. doi: 10.1007/s00018-016-2215-0. Epub 2016 Apr 19.
    Ebola virus encodes a miR-155 analog to regulate importin-α5 expression.

    Suomennosta abstraktista:  Abstract

     Vuonna 2014 alkanut Ebolapurkaus niitti yli 10 000 ihmistä. Nykytieto sopivista lääkkeisä, kliinisistä diagnostisista biomarkkereista ja molekulaarisista mekanisemista joko puuttuu tai on riittämätöntä.
    Tutkijat seuloivat  neljästä virulentista lajista  genomisten säikeiden  runkosilmukoitten rakenteet ja löysivät uuden, oletetun virus-miR-prekursorin, jota Ebolavirus spesifisesti ilmentää. miRNA-prekursorisekvenssi varmistettiin jatkotutkimuksissa käymällä läpi  olemassaolevaa RNA-seq-tietuetta. Prediktiivisiä oli kaksi kypsää miR proteiinia ja ne arvioitiin ihmissolulinjoissa.  Tämä  prediktiivisen mikroRNA.n  oli komboituna kohteeseen, joka tunnistettiin importiini-alfa5:ksi, sen kohdeproteiiniksi.  Tutkijat arvelevat, että tämä miR voisi nopeuttaa  viruksen tekemää isäntäkehon immuunijärjestelmän evaasiota. Lisäksi tämä mikroRNA saattaisi olla kliininen terapeuttinen kohde tai diagnostinen Ebolaviruksen merkitsijä.

    • The 2014 outbreak of Ebola virus caused more than 10,000 human deaths. Current knowledge of suitable drugs, clinical diagnostic biomarkers and molecular mechanisms of Ebola virus infection is either absent or insufficient. By screening stem-loop structures from the viral genomes of four virulence species, we identified a novel, putative viral microRNA precursor that is specifically expressed by the Ebola virus. The sequence of the microRNA precursor was further confirmed by mining the existing RNA-Seq database. Two putative mature microRNAs were predicted and subsequently validated in human cell lines. Combined with this prediction of the microRNA target, we identified importin-α5, which is a key regulator of interferon signaling following Ebola virus infection, as one putative target. We speculate that this microRNA could facilitate the evasion of the host immune system by the virus. Moreover, this microRNA might be a potential clinical therapeutic target or a diagnostic biomarker for Ebola virus.

    KEYWORDS:

    Ebola virus; Host immune system; Interferon signal pathway; MicroRNA

    Ebolan immuunievaasion kiertostrategiasta hyödyntämällä cGAS-STING-signaalitietä

    MBio. 2017 Apr 4;8(2). pii: e00368-17. doi: 10.1128/mBio.00368-17.

    Topoisomerase II Inhibitors Induce DNA Damage-Dependent Interferon Responses Circumventing Ebola Virus Immune Evasion.

    Abstract

    Ebola virus (EBOV) protein VP35 inhibits production of interferon alpha/beta (IFN) by blocking RIG-I-like receptor signaling pathways, thereby promoting virus replication and pathogenesis. A high-throughput screening assay, developed to identify compounds that either inhibit or bypass VP35 IFN-antagonist function, identified five DNA intercalators as reproducible hits from a library of bioactive compounds. Four, including doxorubicin and daunorubicin, are anthracycline antibiotics that inhibit topoisomerase II  and are used clinically as chemotherapeutic drugs.
     These compounds were demonstrated to induce IFN responses in an ATM kinase-dependent manner and to also trigger the DNA-sensing cGAS-STING pathway of IFN induction. These compounds also suppress EBOV replication in vitro and induce IFN in the presence of IFN-antagonist proteins from multiple negative-sense RNA viruses.
    These findings provide new insights into signaling pathways activated by important chemotherapy drugs and identify a novel therapeutic approach for IFN induction that may be exploited to inhibit RNA virus replication.
    IMPORTANCE Ebola virus and other emerging RNA viruses are significant but unpredictable public health threats. Therapeutic approaches with broad-spectrum activity could provide an attractive response to such infections. We describe a novel assay that can identify small molecules that overcome Ebola virus-encoded innate immune evasion mechanisms. This assay identified as hits cancer chemotherapeutic drugs, including doxorubicin. Follow-up studies provide new insight into how doxorubicin induces interferon (IFN) responses, revealing activation of both the DNA damage response kinase ATM and the DNA sensor cGAS and its partner signaling protein STING. The studies further demonstrate that the ATM and cGAS-STING pathways of IFN induction are a point of vulnerability not only for Ebola virus but for other RNA viruses as well, because viral innate immune antagonists consistently fail to block these signals. These studies thereby define a novel avenue for therapeutic intervention against emerging RNA viruses.

    KEYWORDS: ATM signaling; DNA damage; Ebola virus; cGAS-STING pathway; innate immune responses

    Free PMC Article

    G-Quadruplex
     https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5909458/

    EBOV immuunievaasiosta

    https://www.ncbi.nlm.nih.gov/pubmed/28595092

    Virology. 2017 Sep;509:23-34. doi: 10.1016/j.virol.2017.06.002. Epub 2017 Jun 5.

    Ebolavirus protein VP24 interferes with innate immune responses by inhibiting interferon-λ1 gene expression.

     Tiivistelmän suomennosta. Abstract

     Vuosien 2014-2015 Ebolavirusinfektio-Länsi-Afrikassa niitti 11500 kuolonuhria. Kaikenkaikkiaan  sairastuneita oli yli 28000. On tärkeä  saada parempaa käsitystä nääistä hyvin patogeenisista RNA-viruksista.
     Virustautien leviämisen rajoittamisessa  on isäntäkehon luonnollisilla immuunivasteilla avainosuus.
    Tässä tutkimuksessa analysoitiin systemaattisesti kloonattujen EBOV-geenien vaikutuksia  ihmiskehon RNA-virusvastaisten immuunivasteiden  pääteihin:
    RIG-1- viruksentunnistusjärjestelmän aktivoitumisen  kautta  indusoituvaan signaalitiehen
    ja tyypin I ja tyypin III interferonigeenien  ilmenemiseen

    • Ebolaviruses (EBOV) cause severe disease with a recent outbreak in West Africa in 2014-2015 leading to more than 28 000 cases and 11 300 fatalities. This emphasizes the urgent need for better knowledge on these highly pathogenic RNA viruses. Host innate immune responses play a key role in restricting the spread of a viral disease. In this study we systematically analyzed the effects of cloned EBOV genes on the main host immune response to RNA viruses: the activation of RIG-I pathway and type I and III interferon (IFN) gene expression.

     EBOV viruspiorteiini VP24  esti interferonin indusoimat antivirusvasteet, muta sen lisäksi sen havaittiin  tehokkasti estävätn  IIi-tyypin interferoni gamma 1 geenin  ilmentymistä.  Tämä inhiboituminen tapahtui IRF3-aktivaation alavirran puolella ja oli riippuvainen   VP24:n   sitoutumisesta importiiniin ( Siis se esti  IRF3:n pääsyä dimeroituneena IRF7:n kanssa translokoitumaan tumaan) ,
    Saadut  tulokset  painottavat VP24.n tärkeyttä Ebolavirussyklissä ja  VP24 olisikin hyvä kohde lääkekehittelyssä.

    •  EBOV VP24, in addition of inhibiting IFN-induced antiviral responses, was found to efficiently inhibit type III IFN-λ1 gene expression. This inhibition was found to occur downstream of IRF3 activation and to be dependent on VP24 importin binding residues. These results emphasize the importance of VP24 in EBOV infection cycle, making VP24 as an excellent target for drug development.

    KEYWORDS:

    Ebolavirus; Filovirus; Innate immunity; Interferon-λ1; RIG-I pathway; VP24

    Alla olevassa linkissä on IFN-1  ensivasteen sanastoa. 
     https://www.sciencedirect.com/science/article/pii/S1044532315000135

    Filovirusten immuunievaesion pääpiirteitä: RIG-1/RLR sensoreitten hämäys

    https://www.ncbi.nlm.nih.gov/pubmed/21994800
    Viruses. 2011 Sep;3(9):1634-49. doi: 10.3390/v3091634. Epub 2011 Sep 7.

    Filoviral immune evasion mechanisms.

    Suomennosta  abstraktista:  Abstract

     FILOVIRIDAE- virusten perhe ( johon kuuluu Ebolasuku EBOV ja marburgin virus MARV, aiheutavat vaikeita ja  usein letaaleja hemorrhagisia kuumeita ihmisissä. Filovirusinfektioihin littyy  ihmisen taholta   tehoton antivirusvaste, koska virus koodaa immuunoantagonistisia  proteiineja, jotka  tekevät isäntäkehon kyvyttömäksi kehkeyttämään kunnollista luonnollista tai adaptatiivista immuunivastetta
    Jotta ihminen pystyisi kehittämään   soluissaan  antivirusstatuksen,  on ratkaisevaa , että tyypin 1 IFN (interferoni) vaste saadaan ensin muodostumaan ja siitä  sitten seuraa  adaptiivisen immuniteetin vasteiden  aktivoituminen.

    Mutta  useat filovirusten koodaamat komponentit kohdentuvat juuri  näihin  tyypin 1 interferonivasteisiin , sillä virukselle on  ratkaisevan tärkeää  saada  vaimennetuski  juuri tämä vaihe luonnollisessa immuunipuolustuksessa, jotta se pääsee replikoimaan virustaan ja  aiheuttamaan patogeneesin. Miten se toimii?
    esimerkiski EBOV VP35 (virusproteiini) ehkäisee isäntasolun IRF3/7  tekijöiden fosforylaation (aktivoitumisen) TBK1(IKKe-kinaaseilla, Muullakin tavalla se  lamaa virustunnistusjärjestelmää  (RIG-1 kaltaiset reseptorit, RLR)- nimittäin se sakkauttaa viruksen RNA:n siten että herkkä sensori joka tunnsitaa  lyhyitä ja pitkiä yksittäisiä RNA-säikeitä ei pysty tunnistamaan sakkautunutta  virusmateriaalia.

    MARV VP40 proteiini estää   toistakin  tärkeää  immuunipuolustuksen  tietä. Se  estää STAT1/2  fosforylaation  estämällä JAK-perheen kinaaseja.

    EBOV  VP24 virusproteiini estää  aktivoituneen STAT1:n  tumatranslokaation  karyoferiini-alfaproteiinilla.

    Nämä esimekrit  edustavat eri mekanismeja, joita filovirukset käyttävät  vastustaessaan immuunivasteita ja jotka johtavat rajoittuneeseen IFNalfa/beta-tuotantoon ja  heikentyneeseen alavirransignalointiin ( siis  solu ei pääse kehittämään antivirusstatusta eikä saa herätettyä  niitä lukuisia antivirusgeenejään, joita on genomissa yli sata).


    • The Filoviridae family of viruses, which includes the genera Ebolavirus (EBOV) and Marburgvirus (MARV), causes severe and often times lethal hemorrhagic fever in humans. Filoviral infections are associated with ineffective innate antiviral responses as a result of virally encoded immune antagonists, which render the host incapable of mounting effective innate or adaptive immune responses. The Type I interferon (IFN) response is critical for establishing an antiviral state in the host cell and subsequent activation of the adaptive immune responses. Several filoviral encoded components target Type I IFN responses, and this innate immune suppression is important for viral replication and pathogenesis. 
    • For example, EBOV VP35 inhibits the phosphorylation of IRF-3/7 by the TBK-1/IKKε kinases in addition to sequestering viral RNA from detection by RIG-I like receptors.(KUVA)
    •  MARV VP40 inhibits STAT1/2 phosphorylation by inhibiting the JAK family kinases. EBOV VP24 inhibits nuclear translocation of activated STAT1 by karyopherin-α.
    •  The examples also represent distinct mechanisms utilized by filoviral proteins in order to counter immune responses, which results in limited IFN-α/β production and downstream signal
     Bildresultat för MAVS, STING, TRIM, RIG-1,MDA5,  IRF3/7, STAT1/2

    Ebola 2018: Uusi epidemia alkanut Kongon demokraattisessa tasavallassa

     WHO 8.5. 2018
    http://www.who.int/news-room/detail/08-05-2018-new-ebola-outbreak-declared-in-democratic-republic-of-the-congo

    8 May 2018
    News Release
    Geneva/Brazzaville/Kinshasa
    The Government of the Democratic Republic of the Congo declared a new outbreak of Ebola virus disease (EVD) in Bikoro in Equateur Province today (8 May). The outbreak declaration occurred after laboratory results confirmed two cases of EVD.




    https://www.reuters.com/article/us-health-ebola-congo/congo-confirms-first-death-in-latest-ebola-outbreak-idUSKBN1IB13D
     KINSHASA (Reuters) - The Democratic Republic of Congo announced on Thursday the first confirmed death in a new outbreak of Ebola virus and said 11 other people were now confirmed to be infected, including three medical staff.

    Reuters uutiset 10.5. 2018 

    onsdag 2 maj 2018

    Keltakuumevirusraporttia 2018

    2.5. 2018 WHO bulletin
    http://www.who.int/bulletin/volumes/96/5/17-205658/en/

    Results

    We estimated that 923 million people lived in areas of the world where yellow fever was endemic in 2016, spanning 25 holoendemic and 17 non-holoendemic countries or territories (Box 1).

    (Artikkelissa pohditaan matkailun vaikutusta keltakuumeinfektioiden leviämiseen. Karttoja keltakuumemaista esitetaan linkissä).

    HIV tuberkuloosi Etelä-Afrikassa

    2.5. 2018 WHO Bulletin
    http://www.who.int/bulletin/volumes/96/5/18-030518/en/