이 연구는 이안 Goodfellow, 그리고 아르 아리아스에게 수여 마리 퀴리 사내 유럽 원정대 (FP7 유럽 연구 협의회)에게 수여 Wellcome 트러스트 수석의 원정대에 의해 후원되었다. 우리는 우리 자신 애질런트의 bioanalyser를 사용할 수있는 권한을 갖게하고 RNA 샘플을 실행에 도움을 주셔서 이오 홍 청, 닥터 레베카 Robey 및 박사 마이크 스키너 감사드립니다.

<ol>
	<li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Outbreaks+of+gastroenteritis+associated+with+noroviruses+on+cruise+ships--United+States.">Outbreaks of gastroenteritis associated with noroviruses on cruise ships--United States.</a> MMWR Morb. Mortal. Wkly. Rep. 51, 1112-1115 (2002).</li><li>Lopman, B. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epidemiology+and+cost+of+nosocomial+gastroenteritis,+Avon,+England,+2002-2003.">Epidemiology and cost of nosocomial gastroenteritis, Avon, England, 2002-2003.</a> Emerg. Infect. Dis. 10, 2002-2003 (2004).</li><li>Duizer, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laboratory+efforts+to+cultivate+noroviruses.">Laboratory efforts to cultivate noroviruses.</a> J. Gen. Virol. 85, 79-87 (2004).</li><li>Karst, S. M., Wobus, C. E., Lay, M., Davidson, J., Virgin, H. W. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=STAT1-dependent+innate+immunity+to+a+Norwalk-like+virus.">STAT1-dependent innate immunity to a Norwalk-like virus.</a> Science. 299, 1575-1575 (2003).</li><li>Wobus, C. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Replication+of+Norovirus+in+cell+culture+reveals+a+tropism+for+dendritic+cells+and+macrophages.">Replication of Norovirus in cell culture reveals a tropism for dendritic cells and macrophages.</a> PLoS Biol. 2, e432 (2004).</li><li>Bok, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inhibition+of+norovirus+replication+by+morpholino+oligomers+targeting+the+5'-end+of+the+genome.">Inhibition of norovirus replication by morpholino oligomers targeting the 5'-end of the genome.</a> Virology. 380, 328-337 (2008).</li><li>Kim, Y., Thapa, M., Hua, D. H., Chang, K. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biodegradable+nanogels+for+oral+delivery+of+interferon+for+norovirus+infection.">Biodegradable nanogels for oral delivery of interferon for norovirus infection.</a> Antiviral Res. 89, 165-173 (2011).</li><li>McFadden, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Norovirus+Regulation+of+the+Innate+Immune+Response+and+Apoptosis+Occurs+via+the+Product+of+the+Alternative+Open+Reading+Frame+4.">Norovirus Regulation of the Innate Immune Response and Apoptosis Occurs via the Product of the Alternative Open Reading Frame 4.</a> PLoS Pathog. 7, e1002413 (2011).</li><li>Kormelink, R., van Poelwijk, F., Peters, D., Goldbach, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-viral+heterogeneous+sequences+at+the+5'+ends+of+tomato+spotted+wilt+virus+mRNAs.">Non-viral heterogeneous sequences at the 5' ends of tomato spotted wilt virus mRNAs.</a> J. Gen. Virol. 73, 2125-2128 (1992).</li><li>Shuman, S., Hurwitz, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanism+of+mRNA+capping+by+vaccinia+virus+guanylyltransferase:+characterization+of+an+enzyme--guanylate+intermediate.">Mechanism of mRNA capping by vaccinia virus guanylyltransferase: characterization of an enzyme--guanylate intermediate.</a> Proc. Natl. Acad. Sci. U.S.A. 78, 187-191 (1981).</li><li>Jang, S. K., Pestova, T. V., Hellen, C. U., Witherell, G. W., Wimmer, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cap-independent+translation+of+picornavirus+RNAs:+structure+and+function+of+the+internal+ribosomal+entry+site.">Cap-independent translation of picornavirus RNAs: structure and function of the internal ribosomal entry site.</a> Enzyme. 44, 292-309 (1990).</li><li>Chaudhry, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Caliciviruses+differ+in+their+functional+requirements+for+eIF4F+components.">Caliciviruses differ in their functional requirements for eIF4F components.</a> J. Biol. Chem. 281, 25315-25325 (2006).</li><li>Goodfellow, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Calicivirus+translation+initiation+requires+an+interaction+between+VPg+and+eIF+4.">Calicivirus translation initiation requires an interaction between VPg and eIF 4.</a> E. EMBO Rep. 6, 968-972 (2005).</li><li>Herbert, T. P., Brierley, I., Brown, T. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+a+protein+linked+to+the+genomic+and+subgenomic+mRNAs+of+feline+calicivirus+and+its+role+in+translation.">Identification of a protein linked to the genomic and subgenomic mRNAs of feline calicivirus and its role in translation.</a> J. Gen. Virol. 78 ( Pt5 ), 1033-1040 (1997).</li><li>Chaudhry, Y., Skinner, M. A., Goodfellow, I. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recovery+of+genetically+defined+murine+norovirus+in+tissue+culture+by+using+a+fowlpox+virus+expressing+T7+RNA+polymerase.">Recovery of genetically defined murine norovirus in tissue culture by using a fowlpox virus expressing T7 RNA polymerase.</a> J. Gen. Virol. 88, 2091-20100 (2007).</li><li>Ward, V. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recovery+of+infectious+murine+norovirus+using+pol+II-driven+expression+of+full-length+cDNA.">Recovery of infectious murine norovirus using pol II-driven expression of full-length cDNA.</a> Proc. Natl. Acad. Sci. U.S.A. 104, 11050-11055 (2007).</li><li>Yunus, M. A., Chung, L. M., Chaudhry, Y., Bailey, D., Goodfellow, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+an+optimized+RNA-based+murine+norovirus+reverse+genetics+system.">Development of an optimized RNA-based murine norovirus reverse genetics system.</a> J. Virol. Methods. 169, 112-118 (2010).</li><li>Arias, A., Perales, C., Escarmis, C., Domingo, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deletion+mutants+of+VPg+reveal+new+cytopathology+determinants+in+a+picornavirus.">Deletion mutants of VPg reveal new cytopathology determinants in a picornavirus.</a> PLoS One. 5, e10735 (2010).</li><li>Werf, S. v. a. n. d. e. r., Bradley, J., Wimmer, E., Studier, F. W., Dunn, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+infectious+poliovirus+RNA+by+purified+T7+RNA+polymerase.">Synthesis of infectious poliovirus RNA by purified T7 RNA polymerase.</a> Proc. Natl. Acad. Sci. U.S.A. 83, 2330-2334 (1986).</li><li>Bailey, D., Thackray, L. B., Goodfellow, I. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+single+amino+acid+substitution+in+the+murine+norovirus+capsid+protein+is+sufficient+for+attenuation+in+vivo.">A single amino acid substitution in the murine norovirus capsid protein is sufficient for attenuation in vivo.</a> J. Virol. 82, 7725-7728 (2008).</li><li>Bailey, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+analysis+of+RNA+structures+present+at+the+3'+extremity+of+the+murine+norovirus+genome:+the+variable+polypyrimidine+tract+plays+a+role+in+viral+virulence.">Functional analysis of RNA structures present at the 3' extremity of the murine norovirus genome: the variable polypyrimidine tract plays a role in viral virulence.</a> J. Virol. 84, 2859-2870 (2010).</li></ol>

우리는 공개 할게 없다.

여기에서 우리는 세포 배양에서 전염성 MNV의 회복을 허용 서로 다른 두 역방향 유전자 접근 방법을 보여주고있다. 효과적으로 그리고 세포 변이에 의해 인정되는 뒤덮힌 MNV 성적 증명서의 생성을 통해 바이러스성 RNA를 게놈의 5 &#39;끝에 VPg의 covalently 연동을위한 절대적인 요구를 우회 접근 둘 다. 효소 상한 다음에 시험 관내 전사에서 더 효율적이다 성적표가 FPV 상한 효소에 의해 공을 수있는 T7 RNA의 효소를 표현하는 세포에서 전염성 plasmids의 전사보다 전염성 MNV의 회복. 이러한 역방향 유전학 시스템과 복구 바이러스 titres는 감염된 세포 배양 17 (그림 5)에서 정화 바이러스성 VPg 연결된 RNA의 transfection에 의해 얻은 이들과 비슷합니다. 허용 Raw264.7 세포로 덮힌 MNV RNA의 transfection은 transfectio 관련된 실험이 겨우 1-로그 낮은 바이러스 titre를 렌더링N 바이러스성 VPg 연결된 RNA를 (그림 5)가 포함된 감염된 세포로부터 총 RNA의. 이 사실은 이러한 시스템에 의해 생성된 성적의 5 &#39;끝에 VPg 분자의 추가가 VPg에 관련된 세포에 MNV의 감염의 기본 기능적인 측면을 나타낼 수 증가 바이러스 수율 초래할 수 있는지 여부를 확인하기 위해 추가 조사를 장려한다. 다른 RNA 바이러스에 비해 고효율 하나가 유전 시스템은 현재 체외 베꼈는데 RNA에이 virions 19, 20와 실제 감염에 비해 전용 10-100 낮은 titres의 회복을 허용하는 데 사용 반대로 그럼에도 불구하고, 우리는이 역방향 유전학 시스템을 생각한다. 전체적으로 현재의 방법론은 노로 바이러스 분자 생물학 분야에서 앞으로 중요한 단계를 구성하며, 노로 바이러스의 genomes에서 단백질과 RNA의 보존 작품의 기능적 역할을 조사하는 도구를 제공. 이러한 접근 방식은 이미 C와 결합되어이내 10 일 4, 21의 생쥐 - urrent 마우스 모델 사용 가능하고 MNV은 전염성 cDNA로부터 복구하는 것으로 나타났습니다 정보&gt; 80% STAT1-/ 중 치명적인 감염을 일으킬 수 있습니다. 우리가 capsid 단백질 및 생체내 21, 22에서 다소 감쇠 phenotypes을 표시할 다른 호스트 요인 (PTB와 PCBP)의 바인딩에 관여 polypyrimidine 넓이의 유력한 murine 노로 바이러스의 돌연변이를 회복이 시스템의 활용. 또한, 최근에 다시 세포 배양에 복제 효율적 ORF4에서 VF1 단백질을 표현할 수있는 능력이지만 부족한 바이러스 WT MNV 8 관련하여 생쥐에 독성을 감소 것을 증명하고있다. 이러한 연구는 우리가 잠재적인 백신 후보로 조사 수 MNV 연구를 토대로 인간 noroviruses의 감쇠 버전을 설계하는 것이 좋습니다.

<table border="1"><tbody><tr><td> 시약의 이름 </td><td> 회사 </td><td> 카탈로그 번호 </td></tr><tr><td> 염화 리튬의 석출 솔루션 </td><td> Ambion </td><td> AM9480 </td></tr><tr><td> RNA 스토리지 솔루션 </td><td> Ambion </td><td> AM7000 </td></tr><tr><td> MEGAscript T7 스크립트 </td><td> Ambion </td><td> AM1333 </td></tr><tr><td> ScriptCap 677은 시스템 상한 </td><td> Epicentre의 Biotechnologies </td><td> SCCE0610 </td></tr><tr><td> 네온 transfection 시스템 </td><td> Invitrogen </td><td> MPK5000 </td></tr><tr><td> 네온 transfection 시스템 키트 </td><td> Invitrogen </td><td> MPK1025 </td></tr><tr><td> Opti-MEM 전 </td><td> Invitrogen </td><td> 31985070 </td></tr><tr><td> Lipofectamine 2000 Transfection 시약 </td><td> Invitrogen </td><td> 11668-027 </td></tr><tr><td> 애질런트 RNA 600 나노 키트 </td><td> 애질런트 </td><td> 5067-1511 </td></tr><tr><td> 애질런트 2100 BIoanalyzer </td><td> 애질런트 </td><td> G2939AA </td></tr><tr><td> Illustra GFX PCR DNA와 젤 밴드 정제 키트 </td><td> GE 헬스케어 </td><td> 28-9034-70 </td></tr><tr><td> RiboMAX 대규모 RNA 생산 시스템-T7 </td><td> Promega </td><td> P1300 </td></tr></tbody></table>

reverse genetics mediated recovery of infectious murine norovirus

인간 noroviruses 인간 위장염 (GE) 전 세계의 대부분의 경우에 대한 책임이며, 가까운 사람 대 사람의 접촉이 1, 2를 피할 수없는 환경에서 반복 문제입니다. 지난 몇 년 동안 병원에서 발병의 발병률 증가는 자신의 경영 능력뿐만 아니라, 큰 경제적 손실에 상당한 혼란을 초래보고되었습니다. 새로운 항바이러스 접근 방식의 식별은 세포 배양 3에서 생산적인 감염을 완료하는 인간 noroviruses의 무능력으로 인해 제한되었습니다. 밀접하게 인간의 노로 바이러스 네하지만 어떤 관련이 murine 노로 바이러스 (MNV)의 최근의 분리는 세포 5에서 증식 수있는 이러한 병원균 6, 7의 조사를위한 새로운 길을 열었습니다. 새로운 긍정적인 감각의 게놈과 subgenomic RNA 분자의 합성에 MNV 복제 결과, 후기 지난 생에 해당바이러스 게놈의 RD (그림 1). MNV는 ORF1은 게놈의 대부분을 점유하고 polyprotein 전구체에서 발표된 일곱 비 구조 단백질 (NS1-7) 인코딩 중 네 가지 열린 독서 프레임 (ORFs)를 포함합니다. ORF2 및 ORF3는 subgenomic RNA 지역 내에 포함된 및 capsid 단백질 (각각 VP1과 VP2) (그림 1) 인코딩됩니다. 최근, 우리는 ORF2 중복되는 추가 ORF4을 확인하지만, 색다른 열람 프레임에 기능이며, mitochondrial화된 독성 계수 (VF1) 8을 위해 인코딩했습니다. noroviruses 포함하여 긍정적인 감각 RNA 바이러스, 대한 복제는 새로운 uncapped RNA의 genomes의 합성 결과 세포질에서 이루어진다. 바이러스 번역을 촉진하기 위해 바이러스가 세포의 단백질 합성 기계 9-11을 모집 겨냥한 다양한 전략을 악용. 흥미롭게도, 노로 바이러스 번역은 다기능 바이러스성 단백질 프라이머의 VPg에 의해 주도되고covalently 게놈과 subgenomic RNAs 12-14 모두의 5 &#39;끝에 연결되어. 번역의 이러한 복잡한 메커니즘은 기존의 역방향 유전학 방법에 의한 바이러스 복구의 제한된 효율성의 주요 요소가 될 가능성이 높습니다. 여기 murine 노로 바이러스-1 세대 (이것과 함께 MNV으로 함) 5 &#39;끝에 공을 성적을 바탕으로 두 가지 전략을보고합니다. 두번째 접근법은 T7 RNA 중합 효소의 표현 세포의 cDNA MNV의 해독을 수반하는 반면 방법 중 하나는 체외 합성과 바이러스의 RNA의 상한을 모두 포함합니다. MNV의 연구와 작은 동물 모델에 대한 이러한 역방향 유전학 시스템의 가용성 복제 및 pathogenesis 15-17에서 바이러스 시퀀스의 역할을 해부하기 위해 전례없는 능력을 제공합니다.

Watch this Scientific Journal Video about Reverse Genetics Mediated Recovery of Infectious Murine Norovirus at JoVE.com

Reverse Genetics Mediated Recovery of Infectious Murine Norovirus

Noroviruses들이 특성화를위한 위장염 아직 분자 기술의 주요 원인은 아직 비교적 새로운입니다. 여기 murine 노로 바이러스 (MNV), 세포 배양에서 증식 수있는이 속의 유일한 구성원의 효율적인 복구를위한 두 개의 역방향 유전학 방법을보고합니다.

감염성 Murine 노로 바이러스의 역방향 유전학 중재 복구

Human noroviruses are responsible for most cases of human gastroenteritis (GE) worldwide and are recurrent problem in environments where close ...

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Immunology and Infection

16.5K 조회수.  Imperial College London. Noroviruses들이 특성화를위한 위장염 아직 분자 기술의 주요 원인은 아직 비교적 새로운입니다. 여기 murine 노로 바이러스 (MNV), 세포 배양에서 증식 수있는이 속의 유일한 구성원의 효율적인 복구를위한 두 개의 역방향 유전학 방법을보고합니다.

비디오: Reverse Genetics Mediated Recovery of Infectious Murine Norovirus

Using Reverse Genetics to Manipulate the NSs Gene of the Rift Valley Fever Virus MP-12 Strain to Improve Vaccine Safety and Efficacy

Rift Valley fever virus (RVFV), which causes hemorrhagic fever, neurological disorders or blindness in humans, and a high rate abortion and fetal malformation in ruminants1, has been classified as a HHS/USDA overlap select agent and a risk group 3 pathogen. It belongs to the genus Phlebovirus in the family Bunyaviridae and is one of the most virulent members of this family. Several reverse genetics systems for the RVFV MP-12 vaccine strain2,3 as well as wild-type RVFV strains 4-6, including ZH548 and ZH501, have been developed since 2006. The MP-12 strain (which is a risk group 2 pathogen and a non-select agent) is highly attenuated by several mutations in its M- and L-segments, but still carries virulent S-segment RNA3, which encodes a functional virulence factor, NSs. The rMP12-C13type (C13type) carrying 69% in-frame deletion of NSs ORF lacks all the known NSs functions, while it replicates as efficient as does MP-12 in VeroE6 cells lacking type-I IFN. NSs induces a shut-off of host transcription including interferon (IFN)-beta mRNA7,8 and promotes degradation of double-stranded RNA-dependent protein kinase (PKR) at the post-translational level.9,10 IFN-beta is transcriptionally upregulated by interferon regulatory factor 3 (IRF-3), NF-kB and activator protein-1 (AP-1), and the binding of IFN-beta to IFN-alpha/beta receptor (IFNAR) stimulates the transcription of IFN-alpha genes or other interferon stimulated genes (ISGs)11, which induces host antiviral activities, whereas host transcription suppression including IFN-beta gene by NSs prevents the gene upregulations of those ISGs in response to viral replication although IRF-3, NF-kB and activator protein-1 (AP-1) can be activated by RVFV7. . Thus, NSs is an excellent target to further attenuate MP-12, and to enhance host innate immune responses by abolishing the IFN-beta suppression function. Here, we describe a protocol for generating a recombinant MP-12 encoding mutated NSs, and provide an example of a screening method to identify NSs mutants lacking the function to suppress IFN-beta mRNA synthesis. In addition to its essential role in innate immunity, type-I IFN is important for the maturation of dendritic cells and the induction of an adaptive immune response12-14. Thus, NSs mutants inducing type-I IFN are further attenuated, but at the same time are more efficient at stimulating host immune responses than wild-type MP-12, which makes them ideal candidates for vaccination approaches.

The reverse genetics system for the Rift Valley fever virus MP-12 vaccine strain is a useful tool for creating additional MP-12 mutants with increased attenuation and immunogenicity. We describe the protocol to generate and characterize NSs mutant strains.

리프트 밸리 열병 바이러스 백신 안전 및 효능을 향상하기 위해 MP - 12 스트레인의 NSS 진을 조작하는 역방향 유전자를 사용하여

Rift Valley fever virus (RVFV), which causes hemorrhagic fever, neurological disorders or blindness in humans, and a high rate abortion and fetal ...

연구

면역학 및 감염병학

Plaque Assay for Murine Norovirus

Murine norovirus (MNV) is the only member of the Norovirus genus that efficiently grows in tissue culture 1, 2. Cell lysis and cytopathic effect (CPE) are observed during MNV-1 infection of murine dendritic cells or macrophages 1. This property of MNV-1 can be used to quantify the number of infectious particles in a given sample by performing a plaque assay 1. The plaque assay relies on the ability of MNV-1 to lyse cells and to form holes in a confluent cell monolayer, which are called plaques 3.
Multiple techniques can be used to detect viral infections in tissue culture, harvested tissue, clinical, and environmental samples, but not all measure the number of infectious particles (e.g. qRT-PCR). One way to quantify infectious viral particles is to perform a plaque assay 3, which will be described in detail below. A variation on the MNV plaque assay is the fluorescent focus assay, where MNV antigen is immunostained in cell monolayers 4. This assay can be faster, since viral antigen expression precedes plaque formation. It is also useful for titrating viruses unable to form plaques. However, the fluorescent focus assay requires additional resources beyond those of the plaque assay, such as antibodies and a microscope to count focus-forming units. Infectious MNV can also be quantified by determining the 50% Tissue Culture Infective Dose (TCID50) 3. This assay measures the amount of virus required to produce CPE in 50% of inoculated tissue culture cells by endpoint titration 5. However, its limit of detection is higher compared to a plaque assay 4.
In this article, we describe a plaque assay protocol that can be used to effectively determine the number of infectious MNV particles present in biological or environmental samples 1, 4, 6. This method is based on the preparation of 10-fold serial dilutions of MNV-containing samples, which are used to inoculate a monolayer of permissive cells (RAW 264.7 murine macrophage cells). Virus is allowed to attach to the cell monolayer for a given period of time and then aspirated before covering cells with a mixture of agarose and cell culture media. The agar enables the spread of viral progeny to neighboring cells while limiting spread to distantly located cells. Consequently, infected cells are lysed and form holes in the monolayer known as plaques. Upon sufficient spread of virus, plaques become visible following staining of cells with dyes, like neutral red, methylene blue, or crystal violet. At low dilutions, each plaque originates from one infectious viral particle and its progeny, which spread to neighboring cells. Thus, counting the number of plaques allows one to calculate plaque-forming units (PFU) present in the undiluted sample 3.

Here we describe a method to quantify infectious particles of murine norovirus (MNV), which is the only norovirus that efficiently replicates in cell culture. The plaque assay takes advantage of MNV&#x2019;s tropism for murine macrophages and can be adapted for use with biological or environmental samples containing MNV.

손쥐 노로 바이러스에 대한 상패 분석

Murine norovirus (MNV) is the only member of the Norovirus genus that efficiently grows in tissue culture 1, 2. Cell lysis and cytopathic effect (CPE) are ...

Isolating And Immunostaining Lymphocytes and Dendritic Cells from Murine Peyer's Patches

Peyer's patches (PPs) are integral components of the gut-associated lymphoid tissues (GALT) and play a central role in intestinal immunosurveillance and homeostasis. Particulate antigens and microbes in the intestinal lumen are continuously sampled by PP M cells in the follicle-associated epithelium (FAE) and transported to an underlying network of dendritic cells (DCs), macrophages, and lymphocytes. In this article, we describe protocols in which murine PPs are (i) dissociated into single cell suspensions and subjected to flow cytometry and (ii) prepared for cryosectioning and immunostaining. For flow cytometry, PPs are mechanically dissociated and then filtered through 70 &mu;m membranes to generate single cell suspensions free of epithelial cells and large debris. Starting with 20-25 PPs (from four mice), this quick and reproducible method yields a population of &gt;2.5 x 106 cells with &gt;90% cell viability. For cryosectioning, freshly isolated PPs are immersed in Optimal Cutting Temperature (OCT) medium, snap-frozen in liquid nitrogen, and then sectioned using a cryomicrotome. Tissue sections (5-12 &mu;m) are air-dried, fixed with acetone or methanol, and then subjected to immunolabeling.

Isolating And Immunostaining Lymphocytes and Dendritic Cells from Murine Peyer&#039;s Patches

There is an increasing interest in understanding the immunological functions of specific subpopulations of cells in Peyer's patches (PPs), the primary inductive sites of gut-associated lymphoid tissues. Here we outline parallel protocols for preparing PP single cell preparations for flow cytometric analysis and PP cryosections for immunostaining.

림프구와 손쥐 Peyer의 패치에서 수지상 세포를 분리하고 Immunostaining

Peyer's  patches (PPs) are integral components of the gut-associated lymphoid tissues  (GALT) and play a central role in intestinal immunosurveillance and ...

VIGS-Mediated Forward Genetics Screening for Identification of Genes Involved in Nonhost Resistance

Nonhost disease resistance of plants against bacterial pathogens is controlled by complex defense pathways. Understanding this mechanism is important for developing durable disease-resistant plants against wide range of pathogens. Virus-induced gene silencing (VIGS)-based forward genetics screening is a useful approach for identification of plant defense genes imparting nonhost resistance. Tobacco rattle virus (TRV)-based VIGS vector is the most efficient VIGS vector to date and has been efficiently used to silence endogenous target genes in Nicotiana benthamiana.

	In this manuscript, we demonstrate a forward genetics screening approach for silencing of individual clones from a cDNA library in N. benthamiana and assessing the response of gene silenced plants for compromised nonhost resistance against nonhost pathogens, Pseudomonas syringae pv. tomato T1, P. syringae pv. glycinea, and X. campestris pv. vesicatoria. These bacterial pathogens are engineered to express GFPuv protein and their green fluorescing colonies can be seen by naked eye under UV light in the nonhost pathogen inoculated plants if the silenced target gene is involved in imparting nonhost resistance. This facilitates reliable and faster identification of gene silenced plants susceptible to nonhost pathogens. Further, promising candidate gene information can be known by sequencing the plant gene insert in TRV vector. Here we demonstrate the high throughput capability of VIGS-mediated forward genetics to identify genes involved in nonhost resistance. Approximately, 100 cDNAs can be individually silenced in about two to three weeks and their relevance in nonhost resistance against several nonhost bacterial pathogens can be studied in a week thereafter. In this manuscript, we enumerate the detailed steps involved in this screening. VIGS-mediated forward genetics screening approach can be extended not only to identifying genes involved in nonhost resistance but also to studying genes imparting several biotic and abiotic stress tolerances in various plant species.

Virus-induced gene silencing is an useful tool for identifying genes involved in nonhost resistance of plants. We demonstrate the use of bacterial pathogens expressing GFPuv in identifying gene silenced plants susceptible to nonhost pathogens. This approach is easy, fast and facilitates large scale screening and similar protocol can be applied to studying various other plant-microbe interactions.

유전자의 식별을위한 VIGS - 중재 앞으로 유전학 검사는 Nonhost 저항에 참여


	Nonhost disease resistance of plants against bacterial pathogens is controlled by complex defense pathways. Understanding this mechanism is important ...

Organoids as Model for Infectious Diseases: Culture of Human and Murine Stomach Organoids and Microinjection of Helicobacter Pylori

Recently infection biologists have employed stem cell derived cultures to answer the need for new and better models to study host-pathogen interactions. Three cellular sources have been used: Embryonic stem cells (ESC), induced pluripotent stem cells (iPSC) or adult stem cells. Here, culture of mouse and human gastric organoids derived from adult stem cells is described and used for infection with the gastric pathogen Helicobacter pylori. Human gastric glands are isolated from resection material, seeded in a basement matrix and embedded in medium containing growth factors epidermal growth factor (EGF), R-spondin, Noggin, Wnt, fibroblast growth factor (FGF) 10, gastrin and transforming growth factor (TGF) beta inhibitor. In these conditions, gastric glands grow into 3-dimensional organoids containing 4 lineages of the stomach. The organoids expand indefinitely and can be frozen and thawed similarly as cell lines. For infection studies, bacteria are microinjected into the lumen of the organoids. Infected organoids are processed for imaging. The described methods can be adapted to other organoids and infections with other bacteria, viruses or parasites. This allows the study of infection-induced changes in primary cells.

Stem cell derived cultures harbor tremendous potential to model infectious diseases. Here, the culture of mouse and human gastric organoids derived from adult stem cells is described. The organoids are microinjected with the gastric pathogen Helicobacter pylori.

감염증에 대한 모델로 Organoids : 헬리코박터 파이로리의 인간의 문화와 쥐 위장 Organoids 및 미세 주입

Recently infection biologists have employed stem cell derived cultures to answer the need for new and better models to study host-pathogen interactions. ...

Isolation and Flow Cytometric Characterization of Murine Small Intestinal Lymphocytes

The intestines &#8212; which contain the largest number of immune cells of any organ in the body &#8212; are constantly exposed to foreign antigens, both microbial and dietary. Given an increasing understanding that these luminal antigens help shape the immune response and that education of immune cells within the intestine is critical for a number of systemic diseases, there has been increased interest in characterizing the intestinal immune system. However, many published protocols are arduous and time-consuming. We present here a simplified protocol for the isolation of lymphocytes from the small-intestinal lamina propria, intraepithelial layer, and Peyer&#39;s patches that is rapid, reproducible, and does not require laborious Percoll gradients. Although the protocol focuses on the small intestine, it is also suitable for analysis of the colon. Moreover, we highlight some aspects that may need additional optimization depending on the specific scientific question. This approach results in the isolation of large numbers of viable lymphocytes that can subsequently be used for flow cytometric analysis or alternate means of characterization.

There is growing interest in the quantitative characterization of intestinal lymphocytes owing to increasing recognition that these cells play a critical role in a variety of intestinal and systemic diseases. In this protocol, we describe how to isolate single cell populations from different small-intestinal compartments for subsequent flow cytometric characterization.

쥐 소장 림프구의 분리 및 유세포 특성

The intestines &#8212; which contain the largest number of immune cells of any organ in the body &#8212; are constantly exposed to foreign antigens, both ...

Swab Sampling Method for the Detection of Human Norovirus on Surfaces

Human noroviruses are a leading cause of epidemic and sporadic gastroenteritis worldwide. Because most infections are either spread directly via the person-to-person route or indirectly through environmental surfaces or food, contaminated fomites and inanimate surfaces are important vehicles for the spread of the virus during norovirus outbreaks.
We developed and evaluated a protocol using macrofoam swabs for the detection and typing of human noroviruses from hard surfaces. Compared with fiber-tipped swabs or antistatic wipes, macrofoam swabs allow virus recovery (range 1.2-33.6%) from toilet seat surfaces of up to 700 cm2. The protocol includes steps for the extraction of the virus from the swabs and further concentration of the viral RNA using spin columns. In total, 127 (58.5%) of 217 swab samples that had been collected from surfaces in cruise ships and long-term care facilities where norovirus gastroenteritis had been reported tested positive for GII norovirus by RT-qPCR. Of these 29 (22.8%) could be successfully genotyped. In conclusion, detection of norovirus on environmental surfaces using the protocol we developed may assist in determining the level of environmental contamination during outbreaks as well as detection of virus when clinical samples are not available; it may also facilitate monitoring of effectiveness of remediation strategies.

A macrofoam based sampling methodology was developed and evaluated for the detection and quantification of norovirus on environmental hard surfaces.

표면에 인간의 노로 바이러스의 검출을위한 면봉 표본 추출 방법

Human noroviruses are a leading cause of epidemic and sporadic gastroenteritis worldwide. Because most infections are either spread directly via the ...

A Method to Assess Fc-mediated Effector Functions Induced by Influenza Hemagglutinin Specific Antibodies

Antibodies play a crucial role in coupling the innate and adaptive immune responses against viral pathogens through their antigen binding domains and Fc-regions. Here, we describe how to measure the activation of Fc effector functions by monoclonal antibodies targeting the influenza virus hemagglutinin with the use of a genetically engineered Jurkat cell line expressing an activating type 1 Fc-Fc&#947;R. Using this method, the contribution of specific Fc-Fc&#947;R interactions conferred by immunoglobulins can be determined using an in vitro assay.

We describe a method to measure the activation of Fc-mediated effector functions by antibodies that target the influenza virus hemagglutinin. This assay can also be adapted to assess the ability of monoclonal antibodies or polyclonal sera targeting other viral surface glycoproteins to induce Fc-mediated immunity.

독감 조류 특정 항 체에 의해 유도 된 Fc 중재 Effector 기능을 평가 하는 방법

Antibodies play a crucial role in coupling the innate and adaptive immune responses against viral pathogens through their antigen binding domains and ...

Isolating Lymphocytes from the Mouse Small Intestinal Immune System

The intestinal immune system plays an essential role in maintaining the barrier function of the gastrointestinal tract by generating tolerant responses to dietary antigens and commensal bacteria while mounting effective immune responses to enteropathogenic microbes. In addition, it has become clear that local intestinal immunity has a profound impact on distant and systemic immunity. Therefore, it is important to study how an intestinal immune response is induced and what the immunologic outcome of the response is. Here, a detailed protocol is described for the isolation of lymphocytes from small intestine inductive sites like the gut-associated lymphoid tissue Peyer&#39;s patches and the draining mesenteric lymph nodes and effector sites like the lamina propria and the intestinal epithelium. This technique ensures isolation of a large numbers of lymphocytes from small intestinal tissues with optimal purity and viability and minimal cross compartmental contamination within acceptable time constraints. The technical capability to isolate lymphocytes and other immune cells from intestinal tissues enables the understanding of immune responses to gastrointestinal infections, cancers, and inflammatory diseases.

Here we describe a detailed protocol for the isolation of lymphocytes from the inductive sites including the gut-associated lymphoid tissue Peyer&#39;s patches and the draining mesenteric lymph nodes, and the effector sites including the lamina propria and the intestinal epithelium of the small intestinal immune system.

마우스 작은 장의 면역 시스템에서 세포를 분리

The intestinal immune system plays an essential role in maintaining the barrier function of the gastrointestinal tract by generating tolerant responses to ...

Preparation of Murine Submandibular Salivary Gland for Upright Intravital Microscopy

The submandibular salivary gland (SMG) is one of the three major salivary glands, and is of interest for many different fields of biological research, including cell biology, oncology, dentistry, and immunology. The SMG is an exocrine gland comprised of secretory epithelial cells, myofibroblasts, endothelial cells, nerves, and extracellular matrix. Dynamic cellular processes in the rat and mouse SMG have previously been imaged, mostly using inverted multi-photon microscope systems. Here, we describe a straightforward protocol for the surgical preparation and stabilization of the murine SMG in anesthetized mice for in vivo imaging with upright multi-photon microscope systems. We present representative intravital image sets of endogenous and adoptively transferred fluorescent cells, including the labeling of blood vessels or salivary ducts and second harmonic generation to visualize fibrillar collagen. In sum, our protocol allows for surgical preparation of mouse salivary glands in upright microscopy systems, which are commonly used for intravital imaging in the field of immunology.

We describe a protocol to surgically expose and stabilize the murine submandibular salivary gland for intravital imaging using upright intravital microscopy. This protocol is easily adaptable to other exocrine glands of the head and neck region of mice and other small rodents.

똑바로 Intravital 현미경 Murine Submandibular 침 샘의 준비

The submandibular salivary gland (SMG) is one of the three major salivary glands, and is of interest for many different fields of biological research, ...