המחברים מבקשים להודות לקריסטן בולרד-פייבלמן, למילנה וסלינוביץ וקלאודיה רוקר על עזרתם באפיון הווירוס הנגזר משבטים. עבודה זו נתמכה בחלקו על ידי מענקים של המכון הלאומי לאלרגיה ומחלות זיהומיות, NIH תחת מענקים AI114675 (BJG) ו AI067380 (GDE).

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למחברים אין מה לחשוף.

Here we describe a method for the recovery of a bipartite infectious cDNA clone system for ZIKV. Previously described clones for ZIKV suffer from either attenuation or require the addition of introns, making plasmids larger and preventing rescue in insect cells. Infectious virus can be recovered using the two-plasmid clone system in either mammalian or insect cells (data not shown). In addition, virus recovered from this system behaves similarly to wild-type virus in several cell lines, in an immunocompromised mouse mode...

נגיף זיקה (ZIKV: משפחה Flaviviridae : Genus Flavivirus ) הוא flavivirus שנולדו יתוש שהגיע בברזיל ב 2013-14 ו היה קשור לאחר מכן עם התפרצות מסיבית של מחלה חום כי התפשטה ברחבי אמריקה 1 . בנוסף, ZIKV נקשר לתוצאות חמורות של המחלה, כגון תסמונת Guillain-Barré במבוגרים ו מיקרוסקפליה בעוברים ובילודים. מעט ידוע על ZIKV לפני התפשטותה המהירה בחצי הכדור המערבי. זה כלל היעדר כלים מולקולריים, ובכך מעכב מחקר מכניסטי. כלים מולקולריים לווירוסים, כגון שיבוטים cDNA זיהומיות, להקל על החיסון ועל התפתחות טיפולית אנטי ויראלית, ולאפשר הערכה של גורמים גנטיים ויראליים הקשורים פתוגנזה ויראלי דיפרנציאלי, התגובה החיסונית ואת האבולוציה ויראלי. Flavivirus שיבוטים זיהומיות ידועים להיות מאוד לא יציבים חיידקים עקב CRיזמים prokaryotic yptic הנוכחי בגנום שלהם 3 . מספר גישות שימשו לשיפור הבעיה; כולל החדרת טנדם חוזרת במעלה הזרם של רצפים ויראליים 4 , מוטציה של רצפים prokaryotic משוער prokaryotic 5 , פיצול הגנום למספר פלסמידים 6 , וקטורים מספר להעתיק נמוך (כולל כרומוזומים מלאכותיים חיידקים) 7 , 8 והכנסת אינטרונים בגנום ויראלי 9 . מערכת אחת באורך מלא ללא שינויים תוארה עבור ZIKV; עם זאת, שיבוט זה נראה להיות מוחלש בתרבית תאים בעכברים 10 . קבוצות אחרות יש מהונדסים אינטרונים לתוך הגנום ZIKV, המאפשר הפרעה רצפים יציבים חיידקים שיכולים להיות spliced ​​החוצה בתאי יונקים במבחנה לייצור וירוס זיהומיות 11, 12 . בנוסף, מערכת מבוססת PCR בשם זיהום Subgenomic-Amplicons שימש בהצלחה להציל את אב טיפוס MR766 אב טיפוס של ZIKV 13 . הגישה המתוארת כאן אינה דורשת רצפים זרים, אלא משבשת את הגנום באזור של חוסר יציבות גבוהה באמצעות פלסמידים מרובים, אשר בעבר נעשה שימוש בהצלחה עם קדחת צהובה 6 , דנגה 14 , 15 ו נילוס המערבי וירוסים 16 . יתר על כן, תוספת של רצף הפטיטיס D ribozyme על טרמיני הגנומי ויראלי מקל על יצירת של 3 אות &#39;אותנטי ללא צורך הוספת של האתר linearization. בנוסף, הן פלסמידים בנויים וקטור מספר עותק נמוך (pACYC177, ~ 15 עותקים לכל תא) כדי למתן כל רעילות שיורית 17 . הנגיף התאושש מציג פרופיל צמיחה דומהנגיף הוריתי ב עקומות הצמיחה במבחנה 8 שורות תאים המרכיבים מגוון של סוגי תאים נגזר הן יונקים וחרקים, וכן הציג פרופילים פתוגניים זהים בעכברים זיהום, הפצה ושיעורי תעבורה יתושים 18 . להלן, אנו מפרטים בפרוטוקול המתאר כיצד לגדל את פלסמידים משוכפלים זיהומיות, ליצור אורך מלא RNA ויראלי (הגנום ויראלי) במבחנה, ולשחזר וירוס זיהומיות בתרבית תאים. ראשית, אנו מתארים את התפשטות של פלסמידים חיידקים או חיידקים ללא הגברה באמצעות הגברה מעגל הגברה (RCA). לאחר מכן, אנו מראים כיצד שני פלסמידים מתעכלים ולאחר מכן ligated לאחר מכן יחד כדי ליצור וירוס באורך מלא. לבסוף, אנו מתארים את הייצור של רנ&quot;א transcript ו electroporation הבאים שלה לתוך תאים Vero, ואחריו טיטרציה של וירוס התאושש ( איור 1 ). הגישה המתוארת היא מהירה, המאפשרתR ההתאוששות של מניות זיהומיות וירוס בשבועות 1-2.

<table><tbody><tr><td>NEB Stable CompetentE. coli</td><td>New England BioLabs</td><td>C3040H</td><td></td></tr><tr><td>Carbenicillin, Disodium Salt</td><td>various</td><td></td><td></td></tr><tr><td>Zyppy Plasmid Miniprep Kit</td><td>Zymo Research</td><td>D4036</td><td></td></tr><tr><td>ZymoPURE Plasmid Maxiprep Kit</td><td>Zymo Research</td><td>D4202</td><td></td></tr><tr><td>SalI-HF</td><td>New England BioLabs</td><td>R3138S</td><td>20,000 units/ml</td></tr><tr><td>NheI-HF</td><td>New England BioLabs</td><td>R3131S</td><td>20,000 units/ml</td></tr><tr><td>ApaLI</td><td>New England BioLabs</td><td>R0507S</td><td>10,000 units/ml</td></tr><tr><td>EcoRI-HF</td><td>New England BioLabs</td><td>R3101S</td><td>20,000 units/ml</td></tr><tr><td>BamHI-HF</td><td>New England BioLabs</td><td>R3136S</td><td>20,000 units/ml</td></tr><tr><td>HindIII-HF</td><td>New England BioLabs</td><td>R3104S</td><td>20,000 units/ml</td></tr><tr><td>illustra TempliPhi 100 Amplification Kit</td><td>GE Healthcare Life Sciences</td><td>25640010</td><td></td></tr><tr><td>NucleoSpin Gel and PCR Clean-up</td><td>Macherey-Nagel</td><td>740609.5</td><td></td></tr><tr><td>Shrimp Alkaline Phosphatase (rSAP)</td><td>New England BioLabs</td><td>M0371S</td><td>1,000 units/ml</td></tr><tr><td>Alkaline Phosphatase, Calf Intestinal (CIP)</td><td>New England BioLabs</td><td>M0290S</td><td>10,000 units/ml</td></tr><tr><td>T4 DNA Ligase</td><td>New England BioLabs</td><td>M0202S</td><td>400,000units/mL</td></tr><tr><td>HiScribe T7 ARCA mRNA Kit</td><td>New England BioLabs</td><td>E2065S</td><td></td></tr><tr><td>Vero cells</td><td>ATCC</td><td>CCL-81</td><td></td></tr><tr><td>ECM 630 High Throughput Electroporation System</td><td>BTX</td><td>45-0423</td><td>Other machines are acceptable.</td></tr><tr><td>LB Broth with agar (Miller)</td><td>Sigma</td><td>L3147</td><td>Can be homemade as well.</td></tr><tr><td>Terrific Broth</td><td>Sigma</td><td>T0918</td><td>Can be homemade as well.</td></tr><tr><td>Petri Dish</td><td>Celltreat</td><td>229693</td><td></td></tr><tr><td>Culture Tubes</td><td>VWR International</td><td>60818-576</td><td></td></tr><tr><td>T75 flasks</td><td>Celltreat</td><td>229340</td><td></td></tr><tr><td>T182 flasks</td><td>Celltreat</td><td>229350</td><td></td></tr><tr><td>1x PBS</td><td>Corning</td><td>21-040-CV</td><td></td></tr><tr><td>RPMI 1640 with L-glutamine</td><td>Corning</td><td>10-040-CV</td><td></td></tr><tr><td>DMEM with L-glutamine and 4.5 g/L glucose</td><td>Corning</td><td>10-017-CV</td><td></td></tr><tr><td>Fetal Bovine Serum (FBS)</td><td>Atlas Biologicals</td><td>FP-0500-A</td><td></td></tr><tr><td>Tragacanth Powder</td><td>MP Bio</td><td>MP 104792</td><td></td></tr><tr><td>Crystal Violet</td><td>Amresco</td><td>0528-1006</td><td></td></tr><tr><td>Ethanol Denatured</td><td>VWR International</td><td>BDH1156-1LP</td><td></td></tr><tr><td>6 well plate</td><td>Celltreat</td><td>229106</td><td></td></tr><tr><td>12 well plate</td><td>Celltreat</td><td>229111</td><td></td></tr><tr><td>Sequencing Oligos</td><td>IDT</td><td>see table 1</td><td></td></tr><tr><td>Qubit 3.0</td><td>ThermoFisher</td><td>Qubit 3.0</td><td>other methods are acceptable.</td></tr><tr><td>Qubit dsDNA BR Assay Kit</td><td>ThermoFisher</td><td>Q32850</td><td>other methods are acceptable.</td></tr><tr><td>Qubit RNA HS Assay Kit</td><td>ThermoFisher</td><td>Q32852</td><td>other methods are acceptable.</td></tr><tr><td>Class II Biosafety Cabinet</td><td>Varies</td><td>N/A</td><td>This is necessary for live-virus work.</td></tr></tbody></table>

rescue and characterization of recombinant virus from a new world zika virus infectious clone

שיבוטים cDNA זיהומיות לאפשר מניפולציה גנטית של הנגיף, ובכך להקל על עבודה על חיסונים, פתוגנזה, שכפול, שידור האבולוציה ויראלי. כאן אנו מתארים את הבנייה של שיבוט זיהומיות עבור Zika וירוס (ZIKV), אשר כרגע גורם להתפרצות נפץ באמריקה. כדי למנוע רעילות לחיידקים, כי הוא נצפה בדרך כלל עם פלסמידים הנגזרים flavivirus, יצרנו מערכת שני פלסמיד המפריד בין הגנום בגן NS1 והוא יציב יותר מאשר באורך מלא בונה שלא ניתן לשחזר בהצלחה ללא מוטציות. לאחר עיכול קשירת להצטרף שני קטעים, RNA ויראלי באורך מלא יכול להיווצר על ידי שעתוק במבחנה עם פולימרז T7 RNA. בעקבות electroporation של RNA transcribed לתאים, וירוס היה התאושש כי הציג דומה קינטיקה הצמיחה במבחנה ב vivo ארסיות פנוטיפים זיהום בעכברים ויתושים, בהתאמה.

פרוטוקול המתואר כאן מאפשר התאוששות של זיהום נגוע נגוע זיקה וירוס. מניפולציה של שני מערכת פלסמיד שיבוט זיהומיות היא פשוטה כאשר מבוצעת בזהירות, לעומת גירסאות באורך מלא, שהם מאוד לא יציבים (נתונים לא מוצגים). לאחר עיכול קשירת של שתי חתיכות נפרדות, כתרים...

Watch this Scientific Journal Video about Rescue and Characterization of Recombinant Virus from a New World Zika Virus Infectious Clone at JoVE.com

Rescue and Characterization of Recombinant Virus from a New World Zika Virus Infectious Clone

פרוטוקול זה מתאר את ההתאוששות של וירוס זיהום זיהומיות משני שיבוט cDNA שני פלסמיד זיהומיות.

הצלה אפיון של וירוס רקומביננטי מעולם חדש Zika וירוס זיהום מזוהם

Infectious cDNA clones allow for genetic manipulation of a virus, thus facilitating work on vaccines, pathogenesis, replication, transmission and viral ...

rescue-characterization-recombinant-virus-from-new-world-zika-virus

Universidad de Cartagena UDEC

Research

JoVE Journal

Immunology and Infection

9.6K Views.  Colorado State University.  פרוטוקול זה מתאר את ההתאוששות של וירוס זיהום זיהומיות משני שיבוט cDNA שני פלסמיד זיהומיות. 

Video: Rescue and Characterization of Recombinant Virus from a New World Zika Virus Infectious Clone

Generation of Recombinant Influenza Virus from Plasmid DNA

Efforts by a number of influenza research groups have been pivotal in the development and improvement of influenza A virus reverse genetics. Originally established in 1999 1,2 plasmid-based reverse genetic techniques to generate recombinant viruses have revolutionized the influenza research field because specific questions have been answered by genetically engineered, infectious, recombinant influenza viruses. Such studies include virus replication, function of viral proteins, the contribution of specific mutations in viral proteins in viral replication and/or pathogenesis and, also, viral vectors using recombinant influenza viruses expressing foreign proteins 3.

Rescue of influenza A viruses from plasmid DNA is a basic and essential experimental technique that allows influenza researchers to generate recombinant viruses to study multiple aspects in the biology of influenza virus, and to be used as potential vectors or vaccines.

הדור של וירוס שפעת רקומביננטי מ-DNA פלסמיד

Efforts by a number of influenza research groups have been pivotal in the development and improvement of influenza A virus reverse genetics. Originally ...

Generation of Recombinant Arenavirus for Vaccine Development in FDA-Approved Vero Cells

The development and implementation of arenavirus reverse genetics represents a significant breakthrough in the arenavirus field 4. The use of cell-based arenavirus minigenome systems together with the ability to generate recombinant infectious arenaviruses with predetermined mutations in their genomes has facilitated the investigation of the contribution of viral determinants to the different steps of the arenavirus life cycle, as well as virus-host interactions and mechanisms of arenavirus pathogenesis 1, 3, 11 . In addition, the development of trisegmented arenaviruses has permitted the use of the arenavirus genome to express additional foreign genes of interest, thus opening the possibility of arenavirus-based vaccine vector applications 5 . Likewise, the development of single-cycle infectious arenaviruses capable of expressing reporter genes provides a new experimental tool to improve the safety of research involving highly pathogenic human arenaviruses 16 . The generation of recombinant arenaviruses using plasmid-based reverse genetics techniques has so far relied on the use of rodent cell lines 7,19 , which poses some barriers for the development of Food and Drug Administration (FDA)-licensed vaccine or vaccine vectors. To overcome this obstacle, we describe here the efficient generation of recombinant arenaviruses in FDA-approved Vero cells.

Rescue of recombinant arenaviruses from cloned cDNAs, an approach referred to as reverse genetics, allows researchers to investigate the role of specific viral gene products, as well as the contribution of their different specific domains and residues, to many different aspects of the biology of arenavirus. Likewise, reverse genetics techniques in FDA-approved cell lines (Vero) for vaccine development provides novel possibilities for the generation of effective and safe vaccines to combat human pathogenic arenaviruses.

דור של Arenavirus רקומביננטי לפיתוח חיסון בתאי Vero-FDA

The development and implementation of arenavirus reverse genetics represents a significant breakthrough in the arenavirus field  4. The use of cell-based ...

Zika Virus Infectious Cell Culture System and the In Vitro Prophylactic Effect of Interferons

Zika Virus (ZIKV) is an emerging pathogen that is linked to fetal developmental abnormalities such as microcephaly, eye defects, and impaired growth. ZIKV is an RNA virus of the Flaviviridae family. ZIKV is mainly transmitted by mosquitoes, but can also be spread by maternal to fetal vertical transmission as well as sexual contact. To date, there are no reliable treatment or vaccine options available to protect those infected by the virus. The development of a reproducible, effective Zika virus infectious cell culture system is critical for studying the molecular mechanisms of ZIKV replication as well as drug and vaccine development. In this regard, a protocol describing a mammalian cell-based in vitro Zika virus culture system for viral production and growth analysis is reported here. Details on the formation of plaques by Zika virus on a cell monolayer and plaque assay for measuring viral titer are presented. Viral genome replication kinetics and double-stranded RNA genome replicatory intermediates are determined. This culture platform was utilized to screen against a library of a small set of cytokines resulting in the identification of interferon-&#945; (IFN-&#945;), IFN-&#946; and IFN-&#947; as potent inhibitors of Zika viral growth. In summary, an in vitro infectious Zika viral culture system and various virological assays are demonstrated in this study, which has the potential to greatly benefit the research community in elucidating further the mechanisms of viral pathogenesis and the evolution of viral virulence. Antiviral IFN-alpha can further be evaluated as a prophylactic, post-exposure prophylactic, and treatment option for Zika virus infections in high-risk populations, including infected pregnant women.

Zika Virus Infectious Cell Culture System and the In Vitro Prophylactic Effect of Interferons

Zika Virus (ZIKV), an emerging pathogen, is linked to fetal developmental abnormalities and microcephaly. The establishment of an effective infectious cell culture system is crucial for studies of ZIKV replication as well as vaccine and drug development. In this study, various virological assays pertaining to ZIKV are illustrated and discussed.

מערכת תרבית תאי זיהומיות וירוס זיקה ואת<em&gt; במבחנה</em&gt; אפקט מניעתי של אינטרפרונים

Zika Virus (ZIKV) is an emerging pathogen that is linked to fetal developmental abnormalities such as microcephaly, eye defects, and impaired growth. ZIKV ...

Evaluation of Zika Virus-specific T-cell Responses in Immunoprivileged Organs of Infected Ifnar1-/- Mice

The Zika virus (ZIKV) can induce inflammation in immunoprivileged organs (e.g., the brain and testis), leading to the Guillain-Barr&#233; syndrome and damaging the testes. During an infection with the ZIKV, immune cells have been shown to infiltrate into the tissues. However, the cellular mechanisms that define the protection and/or immunopathogenesis of these immune cells during a ZIKV infection are still largely unknown. Herein, we describe methods to evaluate the virus-specific T-cell functionality in these immunoprivileged organs of ZIKV-infected mice. These methods include a) a ZIKV infection and vaccine inoculation in Ifnar1-/- mice; b) histopathology, immunofluorescence, and immunohistochemistry assays to detect the virus infection and inflammation in the brain, testes, and spleen; c) the preparation of a tetramer of ZIKV-derived T-cell epitopes; d) the detection of ZIKV-specific T cells in the monocytes isolated from the brain, testes, and spleen. Using these approaches, it is possible to detect the antigen-specific T cells that have infiltrated into the immunoprivileged organs and to evaluate the functions of these T cells during the infection: potential immune protection via virus clearance and/or immunopathogenesis to exacerbate the inflammation. These findings may also help to clarify the contribution of T cells induced by the immunization against ZIKV.

Evaluation of Zika Virus-specific T-cell Responses in Immunoprivileged Organs of Infected Ifnar1-/- Mice

A protocol to evaluate antigen-specific T-cell responses in the immunoprivileged organs of the Ifnar1-/- murine model for the Zika virus (ZIKV) infection is described. This method is pivotal for investigating the cellular mechanisms of the protection and immunopathogenesis of ZIKV vaccines and is also valuable for their efficacy evaluation.

הערכה של תגובות T-cell Zika וירוס ספציפיים באיברים Immunoprivileged של עכברים נגועים Ifnar1- / -

The Zika virus (ZIKV) can induce inflammation in immunoprivileged organs (e.g., the brain and testis), leading to the Guillain-Barr&#233; syndrome and ...

Quantification of Antibody-dependent Enhancement of the Zika Virus in Primary Human Cells

The recent emergence of the flavivirus Zika and neurological complications, such as Guillain-Barr&#233; syndrome and microcephaly in infants, has brought serious public safety concerns. Among the risk factors, antibody-dependent enhancement (ADE) poses the most significant threat, as the recent re-emergence of the Zika virus (ZIKV) is primarily in areas where the population has been exposed and is in a state of pre-immunity to other closely related flaviviruses, especially dengue virus (DENV). Here, we describe a protocol for quantifying the effect of human serum antibodies against DENV on ZIKV infection in primary human cells or cell lines.

We describe a method to evaluate the effect of pre-existing immunity against dengue virus on the Zika virus infection by using human serum, primary human cells, and infection quantification by quantitative real-time polymerase chain reaction.

כימות של נוגדנים תלויי שיפור של הנגיף Zika בתאי אדם ראשי

The recent emergence of the flavivirus Zika and neurological complications, such as Guillain-Barr&#233; syndrome and microcephaly in infants, has brought ...

Establishing Mouse Models for Zika Virus-induced Neurological Disorders Using Intracerebral Injection Strategies: Embryonic, Neonatal, and Adult

The Zika virus (ZIKV) is a flavivirus currently endemic in North, Central, and South America. It is now established that the ZIKV can cause microcephaly and additional brain abnormalities. However, the mechanism underlying the pathogenesis of ZIKV in the developing brain remains unclear. Intracerebral surgical methods are frequently used in neuroscience research to address questions about both normal and abnormal brain development and brain function. This protocol utilizes classical surgical techniques and describes methods that allow one to model ZIKV-associated human neurological disease in the mouse nervous system. While direct brain inoculation does not model the normal mode of virus transmission, the method allows investigators to ask targeted questions concerning the consequence after ZIKV infection of the developing brain. This protocol describes embryonic, neonatal, and adult stages of intraventricular inoculation of ZIKV. Once mastered, this method can become a straightforward and reproducible technique that only takes a few hours to perform.

Here we describe a method for establishing a model of Zika virus-induced microcephaly in mouse. This protocol includes methods for embryonic, neonatal, and adult-stage intracerebral inoculation of the Zika virus.

יצירת מודלים העכבר עבור וירוס Zika-induced הפרעות נוירולוגיות באמצעות הזרקת גרם אסטרטגיות: עובריים Neonatal, למבוגרים

The Zika virus (ZIKV) is a flavivirus currently endemic in North, Central, and South America. It is now established that the ZIKV can cause microcephaly ...

Neuroscience

Rescue of Recombinant Zika Virus from a Bacterial Artificial Chromosome cDNA Clone

The association of Zika virus (ZIKV) infection with neurological complications during the recent worldwide outbreak and the lack of approved vaccines and/or antivirals have underscored the urgent need to develop ZIKV reverse genetic systems to facilitate the study of ZIKV biology and the development of therapeutic and/or prophylactic approaches. However, like with other flaviviruses, the generation of ZIKV full-length infectious cDNA clones has been hampered due to the toxicity of viral sequences during its amplification in bacteria. To overcome this problem, we have developed a nontraditional approach based on the use of bacterial artificial chromosomes (BACs). Using this approach, the full-length cDNA copy of the ZIKV strain Rio Grande do Norte Natal (ZIKV-RGN) is generated from four synthetic DNA fragments and assembled into the single-copy pBeloBAC11 plasmid under the control of the human cytomegalovirus (CMV) immediate-early promoter. The assembled BAC cDNA clone is stable during propagation in bacteria, and infectious recombinant (r)ZIKV is recovered in Vero cells after transfection of the BAC cDNA clone. The protocol described here provides a powerful technique for the generation of infectious clones of flaviviruses, including ZIKV, and other positive-strand RNA viruses, particularly those with large genomes that have stability problems during bacterial&#160;propagation.

The recent epidemic of Zika virus highlights the importance of establishing reverse genetic approaches to develop vaccines and/or therapeutic strategies. Here, we describe the protocol to rescue an infectious recombinant Zika virus from a full-length cDNA clone assembled in a bacterial artificial chromosome under the control of the human cytomegalovirus immediate-early promoter.

הצלה של וירוס רקומביננטי Zika מתוך כרומוזום מלאכותי בקטריאלי cDNA שיבוט

The association of Zika virus (ZIKV) infection with neurological complications during the recent worldwide outbreak and the lack of approved vaccines ...

Isolation and Quantification of Zika Virus from Multiple Organs in a Mouse

The methods being presented demonstrate laboratory procedures for the isolation of organs from Zika virus infected animals and the quantification of viral load. The purpose of the procedure is to quantify viral titers in peripheral and CNS areas of the mouse at different time points post infection or under different experimental conditions to identify virologic and immunological factors that regulate Zika virus infection. The organ isolation procedures demonstrated allow for both focus forming assay quantification and quantitative PCR assessment of viral titers. The rapid organ isolation techniques are designed for the preservation of virus titer. Viral titer quantification by focus forming assay allows for the rapid throughput assessment of Zika virus. The benefit of the focus forming assay is the assessment of infectious virus, the limitation of this assay is the potential for organ toxicity reducing the limit of detection. Viral titer assessment is combined with quantitative PCR, and using a recombinant RNA copy control viral genome copy number within the organ is assessed with low limit of detection. Overall these techniques provide an accurate rapid high throughput method for the analysis of Zika viral titers in the periphery and CNS of Zika virus infected animals and can be applied to the assessment of viral titers in the organs of animals infected with most pathogens, including Dengue virus.

The goal of the protocol is to demonstrate the techniques used to investigate viral disease by isolating and quantifying Zika virus, from multiple organs in a mouse following infection.

בידוד וקוונפיקציה של וירוס Zika ממספר איברים בעכבר

The methods being presented demonstrate laboratory procedures for the isolation of organs from Zika virus infected animals and the quantification of viral ...

Vector Competence Analyses on Aedes aegypti Mosquitoes using Zika Virus

The procedures presented describe a generalized methodology to infect Aedes aegypti mosquitoes with Zika virus under laboratory conditions to determine the rate of infection, disseminated infection, and potential transmission of the virus in the mosquito population in question. These procedures are widely utilized with various modifications in vector competence evaluations globally. They are important in determining the potential role that a given mosquito (i.e., species, population, individual) may play in the transmission of a given agent.

Vector Competence Analyses on Aedes aegypti Mosquitoes using Zika Virus

The presented protocol can determine the vector competence of Aedes aegypti mosquito populations for a given virus, such as Zika, in a containment setting.

וקטור יכולת ניתוחים על יתושים Aedes aegypti באמצעות וירוס זיקה

The procedures presented describe a generalized methodology to infect Aedes aegypti mosquitoes with Zika virus under laboratory conditions to determine ...

High-throughput Antiviral Assays to Screen for Inhibitors of Zika Virus Replication

Antiviral drug discovery requires the development of reliable biochemical and cellular assays that can be performed in high-throughput screening (HTS) formats. The flavivirus non-structural (NS) proteins are thought to co-translationally assemble on the endoplasmic reticulum (ER) membranes, forming the replication complex (RC). The NS3 and NS5 are the most studied enzymes of the RC and constitute the main targets for drug development due to their crucial roles in viral genome replication. NS3 protease domain, which requires NS2B as its cofactor, is responsible for the cleavage of the immature viral polyprotein into the mature NS proteins, whereas NS5 RdRp domain is responsible for the RNA replication. Herein, we describe in detail the protocols used in replicon-based screenings and enzymatic assays to test large compound libraries for inhibitors of the Zika virus (ZIKV) replication. Replicons are self-replicating subgenomic systems expressed in mammalian cells, in which the viral structural genes are replaced by a reporter gene. The inhibitory effects of compounds on viral RNA replication can be easily evaluated by measuring the reduction in the reporter protein activity. The replicon-based screenings were performed using a BHK-21 ZIKV replicon cell line expressing Renilla luciferase as a reporter gene. To characterize the specific targets of identified compounds, we established in-vitro fluorescence-based assays for recombinantly expressed NS3 protease and NS5 RdRp. The proteolytic activity of the viral protease was measured by using the fluorogenic peptide substrate Bz-nKRR-AMC, while the NS5 RdRp elongation activity was directly detected by the increase of the fluorescent signal of SYBR Green I during RNA elongation, using the synthetic biotinylated self-priming template 3&#8242;UTR-U30 (5&#39;-biotin-U30-ACUGGAGAUCGAUCUCCAGU-3&#39;).

In this work, we describe the protocols used in replicon-based and viral enzyme-based assays to screen for inhibitors of Zika virus replication in a high-throughput screening format.

בדיקות אנטי-ויראליות בעלות תפוקה גבוהה למסך עבור מעכבי שכפול וירוס זיקה

Antiviral drug discovery requires the development of reliable biochemical and cellular assays that can be performed in high-throughput screening (HTS) ...

הצלה אפיון של וירוס רקומביננטי מעולם חדש Zika וירוס זיהום מזוהם

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