The present study was supported by the NIH grants HL120947 (P.C.), HL103868 (P.C.), and the American Heart Association Grant-in-Aid (P.C.)

일반 발언 : 주 멸균 조건에서 계란의 조작과 관련된 모든 절차를 수행하고 멸균 기술 규격 제품을 사용한다. 70 % 에탄올로 모든 장비를 사용하기 전에 사전 깨끗한. 일반적으로, 인플루엔자 바이러스 접종 수확 BSL -2- 실험실에서 수행되어야한다. 그러나,이 프로토콜을 전파하는 데 사용되는 경우 훨씬 더 병원성 인플루엔자 바이러스 (예를 들어, 유행성 및 사전 유행성 균주, 가금류 및 가축, 고병원성 조류 인플루엔자 균주, 1918 년 H1N1 균주에 위험을 초래할 균주), 높은 바이오 안전성 수준 어떤 경우에는, 생물 안전주의 사항과 권한이 필요합니다. 지역 기관 바이오 안전성위원회는 인플루엔자 바이러스와 관련된 모든 연구를 승인해야합니다. 예방 접종에 대한 계란 1. 준비 <ol><li> 적합한 공급 업체에서 혈청 무균 (SPF) 갓 수정 된 조류의 알을 얻습니다. 일반적으로 닭고기 달걀 사용된다. 계란은 우리를해야한다바로 도착 에디션. </li><li> 자동 계란 터너와 가습 계란 인큐베이터에 도착 장소 계란은 계란을 정규적으로 회전시. 자동 계란 터너를 사용할 수없는 경우, 수동으로 적어도 2 ~ 3 회 하루 (장갑을 착용하고 가능한 한 무균 모든 항목을 유지하는 확인) 계란을 회전 할 수 있습니다. </li><li> 37 ° C와 10-11일에 대한 55~60% 습도에서 알을 품어. </li></ol> 2. 계란 캔들링 <ol><li> 배양 7, 8 일 후에 캔들링에 의해 불임 달걀을 확인하는 어두운 방에서 밝은 빛에 계란을 검사 할 수 달걀 캔 들러를 사용합니다. <ol><li> 70 % 에탄올로 계란 캔 들러를 닦습니다. 종종 장갑을 변경하고 병원체에 의한 오염의 위험을 최소화하기 위해 70 % 에탄올로 소독. </li><li> 인큐베이터에서 계란을 제거하고 빈 달걀 종이팩에 배치합니다. </li><li> 실내 조명을 끄고. </li><li> 캔 들러에 대해 한 번에 각 계란 하나의 큰 끝을 잡고. </li><li> determin하기 위해 달걀을 준수전자는 비옥 한 또는 불임 인 경우. 참고 : 콩 모양 배에 이르는 얇은 혈관이 명확하게 볼 수 있어야합니다. 미 수정 달걀은 볼 달걀 노른자와 작은 핏자국으로 표시됩니다. </li></ol></li><li> 미 수정있는 계란을 폐기하고, 인큐베이터 가능한 계란을 반환합니다. 30 분 동안 인큐베이터 밖에서 알을 두지 마십시오. 계란의 상태를 확인할 수없는 경우이를 표시하고 나중에 관찰. </li></ol> 바이러스 접종 3. 준비 <ol><li> 10 mM의 HEPES (PH 7.4)를 포함 멸균 PBS에서 104 PFU / ㎖ - 10 3 인플루엔자 바이러스 주식을 희석. 중요한 단계 : 즉시 사용하기 전에 바이러스 주식을 희석하고 얼음에 모든 시간을 희석 바이러스를 유지합니다. </li></ol> 뇨 경로를 통해 4. 인플루엔자 바이러스 예방 접종 <ol><li> 바이러스 접종 (10 일 또는 11)의 날에 다시 계란을 촛불과 죽은 배아를 제거 할 수 있습니다. 살아있는 배아를 구별계란 내부 이동을 찾고. </li><li> 인큐베이터에서 세 알을 제거하고 공기 주머니 위로 별도의 홀더에 계란을 마련. </li><li> 영구 마커와 계란의 공기 공간을 표시합니다. </li><li> 70 % 에탄올로 공기 공간 위에 달걀 껍질을 씻으십시오. </li><li> 계란 판지 및 바이오 안전성 후드 (BSL-2)에 공기 공간을 최대로 계란을 넣습니다. </li><li> 각 계란의 공기 주머니를 통해 껍질에 작은 구멍을 주먹으로 멸균 18G 바늘을 사용합니다. 배아 또는 노른자를 찔러 방지하기 위해 너무 깊이 바늘을 삽입하지 않도록주의하십시오. </li><li> 멸균 1 ML의 주사기에 희석 된 인플루엔자 바이러스를 그려 22G 바늘을 연결합니다. </li><li> 조심스럽게 뇨 공동으로 45 ° 각도로 바늘과 주사기를 진행합니다. </li><li> 희석 인플루엔자 바이러스 0.2ml를 주입한다. </li><li> 다른 두 계란 주사를 반복 한 다음 주사기와 바늘을 폐기​​합니다. </li><li> 글루건 (또는 녹은 파라핀 왁스)에서 접착제의 드롭 구멍을 밀봉합니다. B전자 접착제 계란 내부에 누출되지 않도록주의. </li><li> 공기 공간이 위쪽으로 지적와 계란 인큐베이터에 계란을 다시 배치합니다. </li><li> 반복 4.2 단계 - 4.12 모든 계란 접종 때까지. </li></ol> 5. 보육 시간 <ol><li> 37 ° C와 ~ 60 %의 습도에서 끄지 않고 감염된 계란을 품어. </li><li> 인플루엔자 바이러스 유형에 따라 최적의 배양 시간을 선택한다. 48 시간 동안 인플루엔자를 품어; 72 시간 동안 인플루엔자 B와 C를 품어. </li></ol> 6. 인플루엔자 바이러스 수확 <ol><li> 인큐베이션 기간 후, 배아를 죽이고 피 감염된 막액 오염의 위험을 최소화하기 위해 혈관을 수축 4 시간 (또는 O / N) 이상 동안 39 ° C에서 계란을 냉각. 수율을 감소 바이러스, 흡수로부터 적혈구를 방지하기 위해 이렇게. 또한, 냉각 계란 30 분 -20 ° C에서; 그러나 혈액이 오염의 위험을 증가시킨다. </li><li> 계란이 충분히 냉각 된 후에, 바이오 안전성 후드에 계란을 전송합니다. 공기 주머니가 위로 향하게 회사 홀더에 달걀을 놓습니다. 70 % 에탄올로 달걀 표면을 청소합니다. </li><li> 공기 주머니 위에 달걀 껍질을 열 멸균 가위를 사용합니다. 융모 막을 파괴하지 않도록주의하면서 공기 주머니 주위에 껍질을 제거합니다. </li><li> 멸균 무딘 집게로 융모 막을 엽니 다. 조심스럽게 배아와 작은 주걱이나 숟가락으로 난황을 옆으로 이동합니다. 노른자를 파열되지 않도록주의하십시오. </li><li> 1 에펜 도르프 피펫을 사용하여 조심스럽게 막액를 수집합니다. 필요한 경우, 옆으로 약간 많은 유체 가능한 수집 계란을 기울입니다. </li><li> 50 ㎖ 플라스틱 원뿔 관에 모든 계란에서 막액을 결합합니다. 바이러스 수확하는 동안 항상 얼음에 튜브를 유지합니다. 하나의 계란 생산량 5 - 약간 노란 유체 10 ㎖. </li><li> 4에서 10 분 동안 1,000 XG에서 바이러스 - 함유 막액 스핀6; C 파편 펠렛합니다. 새로운 50 ㎖ 튜브에 맑은 액체를 이동시켜 얼음에 보관. BSL-2 폐기물 용기에 달걀을 폐기하십시오. </li></ol> 7. 저장 <ol><li> 즉시 뇨 명확히 유체 (예를 들어, 50, 100 또는 500 UL 분량 씩) 나누어지는 스냅 동결을 액체 질소에. 냉동 바이러스 주식 장기 저장을 위해 -80 ° C 냉장고에 전송합니다. </li></ol>

<ol>
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The authors have nothing to disclose.

인플루엔자는 질병의 큰 부담을 글로벌 초래하고 작업 폐 손상 (7)의 병인을 이해로 계속된다. 이 치명적인 질병의 촉진 연구, 다양한 방법 인플루엔자 바이러스 (6)을 전파하기 위해 개발되었습니다. 여기서는 닭고기 계란 인플루엔자 바이러스를 생산하는 방법을 설명한다. 이 방법의 장점은 높은 재현성 있다는 종종 시험 관내 연구에 필요한 높은 역가 인플루엔자 바이러?...

인플루엔자는 인간의 건강에 큰 위협이되고 있습니다. 그것은 큰 글로벌 부담이 매년 전세계에서 1 500000 사망까지 일으키는 잠재적으로 치명적인 호흡기 질환이다. 인플루엔자 바이러스는 가족 오르 쏘 믹소 바이러스과 (orthomixoviridae)에있는 자신의 게놈 1,2 8 음의 감각 단일 가닥 RNA를 수행한다. 바이러스 게놈의 높은 가변성 (즉, 항원 &quot;드리프트&quot;)는 장기 면역을 방지 할 수 있습니다. 또한, 인플루엔자 항 바이러스제 3 더욱 강하다. 2009 H1N1 인플루엔자 대유행 인플루엔자 질병 (유행성 변형, 항 바이러스 성, 지연 백신 생산)과 관련된 모든 어려운 문제를 강조했다. 백신 제제는 대부분 병원성 인플루엔자 균주 4 (H1N1, H3N2 인플루엔자 B 각각 하나씩)에 대한 세계 보건기구 (WHO)에 의해 매년 결정된다. 이 방법은 예측 인플루엔자 균주를 기반으로하기 때문에들, 병원성 균주는 때때로 잘못 파악하고 백신 유효성이 크게 저하된다. 더욱이, 신규 한 인플루엔자 균주의 출현은이 전염병을 일으키는 이러한 예방 프로그램을 회피 할 수있다. 범용 인플루엔자 백신의 생성은 5 애매하고있다. 따라서 연구는 폐 손상의 기전을 이해하기에 계속해야합니다. 시설 실험실 연구에, 여러 가지 방법이 바이러스 분리 및 전파 (6)을 위해 개발되었다. 인간 인플루엔자 바이러스는 포유 동물 세포의 다양한 기판들에서 증폭 될 수있다. 그러나, 대량으로 생성하는 높은 역가의 바이러스는 가장 유정란에 달성된다. 다음 프로토콜은 인플루엔자에 대한 기존의 바이러스 주식에서 바이러스 전파 및 저장 기술에 대해 설명합니다.

<table border="0" cellpadding="0" cellspacing="0" width="873">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:353px;">Name of Reagent/ Equipment</td>
			<td style="width:225px;">Company</td>
			<td style="width:128px;">Catalog Number</td>
			<td style="width:167px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:353px;">Phosphate buffered saline (PBS)</td>
			<td style="width:225px;">Cellgro&#160;</td>
			<td style="width:128px;">21-040-CV</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">serum pathogen-free (SPF) fertilized chicken eggs&#160;</td>
			<td>VALO BioMedia</td>
			<td style="width:128px;">n/a</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">humidified egg incubator&#160;</td>
			<td>FARM iNNOVATORS</td>
			<td>Model 2100</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">automatic egg turner</td>
			<td>FARM iNNOVATORS</td>
			<td>Model 3200</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">egg candler</td>
			<td>FARM iNNOVATORS</td>
			<td>Model 3300&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:353px;">1 ml syringe</td>
			<td style="width:225px;">BD Bioscience</td>
			<td style="width:128px;">309659</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:353px;">18G needle</td>
			<td style="width:225px;">BD Bioscience</td>
			<td style="width:128px;">305196</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:353px;">20G / 22G needle</td>
			<td style="width:225px;">BD Bioscience</td>
			<td style="width:128px;">305176 / 305156</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:353px;">HEPES</td>
			<td style="width:225px;">Sigma-Aldrich</td>
			<td style="width:128px;">H3375</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:353px;">Ethanol, &#62;99.5%</td>
			<td style="width:225px;">Sigma-Aldrich</td>
			<td style="width:128px;">459844</td>
			<td>diluted to 70% using water</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:353px;">glue gun &#34;Ad tech Hi Temp Project Pro&#34;</td>
			<td style="width:225px;">Ad tech, Adhesive Technologies, Inc.</td>
			<td>Model 1105</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:353px;">glue &#34;Ad tech MINI SIZE, Multi Temp&#34;</td>
			<td style="width:225px;">Ad tech, Adhesive Technologies, Inc.</td>
			<td>220-34ZIP30</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:353px;">MDCK cells</td>
			<td style="width:225px;">ATCC</td>
			<td>CRL-2935</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:353px;">Washed Pooled Turkey Red Blood Cells, 10%</td>
			<td style="width:225px;">Lampire Biological Laboratories</td>
			<td>724908</td>
			<td></td>
		</tr>
	</tbody>
</table>

influenza virus propagation in embryonated chicken eggs

인플루엔자 감염은 약 36,000 명이 사망하고 미국에서 20 만 명 이상의 입원 매년와 연결되어 있습니다. 돌연변이 다시 구색 인한 새로운 인플루엔자 바이러스 균주의 연속 출현 바이러스의 제어를 복잡하게하고 신규 약물과 백신의 개발을 필요로 영구. 인플루엔자의 실험실 기반의 연구는 바이러스의 전파에 대한 안정적이고 비용 효율적인 방법이 필요합니다. 여기에, 포괄적 인 프로토콜은 지속적으로 높은 역가의 바이러스 주식을 산출 비옥 한 닭 계란에 인플루엔자 바이러스 전파, 제공됩니다. 11 일 - 간단히 말해, 혈청 무균 (SPF) 수정 된 닭고기 달걀은 37 ° C와 10 55~60% 습도에서 배양된다. 이 기간 동안, 배아 발달 쉽게 알 캔 들러를 사용하여 모니터 할 수있다. 바이러스 접종은 바늘을 사용하여 공동 내로 뇨 바이러스 스톡의 주사에 의해 수행된다. 37 ° C에서 배양 2 일 후, 계란은4 ° C에서 적어도 4 시간 동안 냉장. 공기 주머니와 상기 멤브레인 융모 껍질을주의 깊게 개방하고, 바이러스를 함유 막액 수확된다. 유체를 원심 분리에 의해 먼지로부터 클리어 분주 장기 저장에 대해 -80 ° C에 전달된다. 다량 보통이 프로토콜에 의해 달성되고 높은 바이러스 역가 (바이러스 - 함유 달걀 당 유체를 5-10 ml)을 대량으로 요구하는 시험 관내 연구를 위해, 특히 바이러스 제제 우리 유리한 방법 계란의 사용량을 만들었다 바이러스의 것과 동일한 바이러스 주식의 높은 복용량이 필요하다.

여러 방법은 인플루엔자 바이러스 역가를 위해 개발되었다. 적절한 방법을 선택하는 하나의 고려 사항은 일부 가능한 비리을 평가하는 관계없이 다른 사람이 감염을 기반으로하는 반면 생존 능력 (예를 들어, 헤 마글 루티 닌 분석)의 총 입자를 결정하는 것입니다 (예를 들면, 상패 분석) 6. 여기서, 마우스 구성된 인플루엔자 바이러스 (A는 / PR / 34분의 8) 접종 닭고기 계란에?...

Watch this Scientific Journal Video about Influenza Virus Propagation in Embryonated Chicken Eggs at JoVE.com

Influenza Virus Propagation in Embryonated Chicken Eggs

Fertile chicken eggs are widely used to produce large amounts of human influenza A virus as they provide a convenient and cost-effective system to prove high yields of virus.

인간 백신 닭 계란에 인플루엔자 바이러스 전파

Influenza infection is associated with about 36,000 deaths and more than 200,000 hospitalizations every year in the United States. The continuous ...

influenza-virus-propagation-in-embryonated-chicken-eggs

Research

JoVE Journal

Immunology and Infection

42.5K 조회수.  Cedars-Sinai Medical Center. Fertile chicken eggs are widely used to produce large amounts of human influenza A virus as they provide a convenient and cost-effective system to prove high yields of virus.

비디오: Influenza Virus Propagation in Embryonated Chicken Eggs

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.

플라스미드 DNA의 재조합 독감 바이러스의 생성

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

연구

면역학 및 감염병학

High-throughput Detection Method for Influenza Virus

Influenza virus is a respiratory pathogen that causes a high degree of morbidity and mortality every year in multiple parts of the world. Therefore, precise diagnosis of the infecting strain and rapid high-throughput screening of vast numbers of clinical samples is paramount to control the spread of pandemic infections. Current clinical diagnoses of influenza infections are based on serologic testing, polymerase chain reaction, direct specimen immunofluorescence and cell culture 1,2.
Here, we report the development of a novel diagnostic technique used to detect live influenza viruses. We used the mouse-adapted human A/PR/8/34 (PR8, H1N1) virus 3 to test the efficacy of this technique using MDCK cells 4. MDCK cells (104 or 5 x 103 per well) were cultured in 96- or 384-well plates, infected with PR8 and viral proteins were detected using anti-M2 followed by an IR dye-conjugated secondary antibody. M2 5 and hemagglutinin 1 are two major marker proteins used in many different diagnostic assays. Employing IR-dye-conjugated secondary antibodies minimized the autofluorescence associated with other fluorescent dyes. The use of anti-M2 antibody allowed us to use the antigen-specific fluorescence intensity as a direct metric of viral quantity. To enumerate the fluorescence intensity, we used the LI-COR Odyssey-based IR scanner. This system uses two channel laser-based IR detections to identify fluorophores and differentiate them from background noise. The first channel excites at 680 nm and emits at 700 nm to help quantify the background. The second channel detects fluorophores that excite at 780 nm and emit at 800 nm. Scanning of PR8-infected MDCK cells in the IR scanner indicated a viral titer-dependent bright fluorescence. A positive correlation of fluorescence intensity to virus titer starting from 102-105 PFU could be consistently observed. Minimal but detectable positivity consistently seen with 102-103 PFU PR8 viral titers demonstrated the high sensitivity of the near-IR dyes. The signal-to-noise ratio was determined by comparing the mock-infected or isotype antibody-treated MDCK cells.
Using the fluorescence intensities from 96- or 384-well plate formats, we constructed standard titration curves. In these calculations, the first variable is the viral titer while the second variable is the fluorescence intensity. Therefore, we used the exponential distribution to generate a curve-fit to determine the polynomial relationship between the viral titers and fluorescence intensities. Collectively, we conclude that IR dye-based protein detection system can help diagnose infecting viral strains and precisely enumerate the titer of the infecting pathogens.

This method describes the use of Infrared dye based imaging system for detection of H1N1 in bronchioalveolar lavage (BAL) fluid of infected mice at a high sensitivity. This methodology can be performed in a 96- or 384-well plate, requires &lt;10 &mu;l volume of test material and has the potential for concurrent screening of multiple pathogens.

인플루엔자 바이러스에 대한 높은 처리량 검출 방법

Influenza virus is a respiratory pathogen that causes a high degree of morbidity and mortality every year in multiple parts of the world. Therefore, ...

Affinity Purification of Influenza Virus Ribonucleoprotein Complexes from the Chromatin of Infected Cells

Like all negative-strand RNA viruses, the genome of influenza viruses is packaged in the form of viral ribonucleoprotein complexes (vRNP), in which the single-stranded genome is encapsidated by the nucleoprotein (NP), and associated with the trimeric polymerase complex consisting of the PA, PB1, and PB2 subunits. However, in contrast to most RNA viruses, influenza viruses perform viral RNA synthesis in the nuclei of infected cells. Interestingly, viral mRNA synthesis uses cellular pre-mRNAs as primers, and it has been proposed that this process takes place on chromatin1. Interactions between the viral polymerase and the host RNA polymerase II, as well as between NP and host nucleosomes have also been characterized1,2.
Recently, the generation of recombinant influenza viruses encoding a One-Strep-Tag genetically fused to the C-terminus of the PB2 subunit of the viral polymerase (rWSN-PB2-Strep3) has been described. These recombinant viruses allow the purification of PB2-containing complexes, including vRNPs, from infected cells. To obtain purified vRNPs, cell cultures are infected, and vRNPs are affinity purified from lysates derived from these cells. However, the lysis procedures used to date have been based on one-step detergent lysis, which, despite the presence of a general nuclease, often extract chromatin-bound material only inefficiently. 
Our preliminary work suggested that a large portion of nuclear vRNPs were not extracted during traditional cell lysis, and therefore could not be affinity purified. To increase this extraction efficiency, and to separate chromatin-bound from non-chromatin-bound nuclear vRNPs, we adapted a step-wise subcellular extraction protocol to influenza virus-infected cells. Briefly, this procedure first separates the nuclei from the cell and then extracts soluble nuclear proteins (here termed the "nucleoplasmic" fraction). The remaining insoluble nuclear material is then digested with Benzonase, an unspecific DNA/RNA nuclease, followed by two salt extraction steps: first using 150 mM NaCl (termed "ch150"), then 500 mM NaCl ("ch500") (Fig. 1). These salt extraction steps were chosen based on our observation that 500 mM NaCl was sufficient to solubilize over 85% of nuclear vRNPs yet still allow binding of tagged vRNPs to the affinity matrix.
After subcellular fractionation of infected cells, it is possible to affinity purify PB2-tagged vRNPs from each individual fraction and analyze their protein and RNA components using Western Blot and primer extension, respectively. Recently, we utilized this method to discover that vRNP export complexes form during late points after infection on the chromatin fraction extracted with 500 mM NaCl (ch500)3.

Influenza viruses replicate their RNA genome in association with host-cell chromatin. Here, we present a method to purify intact viral ribonucleoprotein complexes from the chromatin of infected cells. Purified viral complexes can be analyzed by both Western blot and primer extension of protein and RNA content, respectively.

감염된 세포의 염색질에서 인플루엔자 바이러스 Ribonucleoprotein 컴플렉스의 동질 정제

Like all negative-strand RNA viruses, the genome of influenza viruses is packaged in the form of viral ribonucleoprotein complexes (vRNP), in which the ...

Propagation of Homalodisca coagulata virus-01 via Homalodisca vitripennis Cell Culture

The glassy-winged sharpshooter (Homalodisca vitripennis) is a highly vagile and polyphagous insect found throughout the southwestern United States. These insects are the predominant vectors of Xylella fastidiosa (X. fastidiosa), a xylem-limited bacterium that is the causal agent of Pierce&#39;s disease (PD) of grapevine. Pierce&#8217;s disease is economically damaging; thus, H. vitripennis have become a target for pathogen management strategies. A dicistrovirus identified as Homalodisca coagulata virus-01 (HoCV-01) has been associated with an increased mortality in H. vitripennis populations. Because a host cell is required for HoCV-01 replication, cell culture provides a uniform environment for targeted replication that is logistically and economically valuable for biopesticide production. In this study, a system for large-scale propagation of H. vitripennis cells via tissue culture was developed, providing a viral replication mechanism. HoCV-01 was extracted from whole body insects and used to inoculate cultured H. vitripennis cells at varying levels. The culture medium was removed every 24 hr for 168 hr, RNA extracted and analyzed with qRT-PCR. Cells were stained with trypan blue and counted to quantify cell survivability using light microscopy. Whole virus particles were extracted up to 96 hr after infection, which was the time point determined to be before total cell culture collapse occurred. Cells were also subjected to fluorescent staining and viewed using confocal microscopy to investigate viral activity on F-actin attachment and nuclei integrity. The conclusion of this study is that H. vitripennis cells are capable of being cultured and used for mass production of HoCV-01 at a suitable level to allow production of a biopesticide.

Propagation of Homalodisca coagulata virus-01 via Homalodisca vitripennis Cell Culture

Here we present a protocol to propagate Homalodisca vitripennis cells and HoCV-1 in vitro. Medium was removed from HoCV-1 positive cultures and RNA extracted every 24 hr for 168 hr. Cell survivability was quantified by trypan blue staining. Whole virus particles were extracted post-infection. Extracted RNA was quantified by qRT-PCR.

의 전파<em&gt; Homalodisca의 coagulata 바이러스-01</em&gt;를 통해<em&gt; Homalodisca vitripennis</em&gt; 세포 배양

The glassy-winged sharpshooter (Homalodisca vitripennis) is a highly vagile and polyphagous insect found throughout the southwestern United States. These ...

Nasal Wipes for Influenza A Virus Detection and Isolation from Swine

Surveillance for influenza A viruses in swine is critical to human and animal health because influenza A virus rapidly evolves in swine populations and new strains are continually emerging. Swine are able to be infected by diverse lineages of influenza A virus making them important hosts for the emergence and maintenance of novel influenza A virus strains. Sampling pigs in diverse settings such as commercial swine farms, agricultural fairs, and live animal markets is important to provide a comprehensive view of currently circulating IAV strains. The current gold-standard ante-mortem sampling technique (i.e. collection of nasal swabs) is labor intensive because it requires physical restraint of the pigs. Nasal wipes involve rubbing a piece of fabric across the snout of the pig with minimal to no restraint of the animal. The nasal wipe procedure is simple to perform and does not require personnel with professional veterinary or animal handling training. While slightly less sensitive than nasal swabs, virus detection and isolation rates are adequate to make nasal wipes a viable alternative for sampling individual pigs when low stress sampling methods are required. The proceeding protocol outlines the steps needed to collect a viable nasal wipe from an individual pig.

The authors present a protocol to collect swine nasal wipes to detect and isolate influenza A viruses.

돼지에서 인플루엔자 바이러스 탐지 및 격리를위한 코 닦음

Surveillance for influenza A viruses in swine is critical to human and animal health because influenza A virus rapidly evolves in swine populations and ...

Measuring Attachment and Internalization of Influenza A Virus in A549 Cells by Flow Cytometry

Attachment to target cells followed by internalization are the very first steps of the life cycle of influenza A virus (IAV). We provide here a detailed protocol for measuring relative changes in the amount of viral particles that attach to A549 cells, a human lung epithelial cell line, as well as in the amount of particles that are internalized into the cell. We use biotinylated virus which can be easily detected following staining with Cy3-labeled streptavidin (STV-Cy3). We describe the growth, purification and biotinylation of A/WSN/33, a widely used IAV laboratory strain. Cold-bound biotinylated IAV particles on A549 cells are stained with STV-Cy3 and measured using flow cytometry. To investigate uptake of viral particles, cold-bound virus is allowed to internalize at 37 &#176;C. In order to differentiate between external and internalized viral particles, a blocking step is applied: Free binding spots on the biotin of attached virus on the cell surface are bound by unlabeled streptavidin (STV). Subsequent cell permeabilization and staining with STV-Cy3 then enables detection of internalized viral particles. We present a calculation to determine the relative amount of internalized virus. This assay is suitable to measure effects of drug-treatments or other manipulations on attachment or internalization of IAV.

We present a protocol describing a semi-quantitative method for measuring both, the attachment of influenza A virus to A549 cells, as well as the internalization of virus particles into the target cells by flow cytometry.

유동 세포 계측법에 의해 A549 세포의 부착 및 국제화 인플루엔자의 바이러스를 측정

Attachment to target cells followed by internalization are the very first steps of the life cycle of influenza A virus (IAV). We provide here a detailed ...

Neutrophil Isolation and Analysis to Determine their Role in Lymphoma Cell Sensitivity to Therapeutic Agents

Neutrophils are the most abundant (40% to 75%) type of white blood cells and among the first inflammatory cells to migrate towards the site of inflammation. They are key players in the innate immune system and play major roles in cancer biology. Neutrophils have been proposed as key mediators of malignant transformation, tumor progression, angiogenesis and in the modulation of the antitumor immunity; through their release of soluble factors or their interaction with tumor cells. To characterize the specific functions of neutrophils, a fast and reliable method is coveted for in vitro isolation of neutrophils from human blood. Here, a density gradient separation method is demonstrated to isolate neutrophils as well as mononuclear cells from the blood. The procedure consists of layering the density gradient solution such as Ficoll carefully above the diluted blood obtained from patients diagnosed with chronic lymphocytic leukemia (CLL), followed by centrifugation, isolation of mononuclear layer, separation of neutrophils from RBCsby dextran then lysis of residual erythrocytes. This method has been shown to isolate neutrophils &#8805; 90 % pure. To mimic the tumor microenvironment, 3-dimensional (3D) experiments were performed using basement membrane matrix such as Matrigel. Given the short half-life of neutrophils in vitro, 3D experiments with fresh human neutrophils cannot be performed. For this reason promyelocytic HL60 cells are differentiated along the granulocytic pathway using the differentiation inducers dimethyl sulfoxide (DMSO) and retinoic acid (RA). The aim of our experiments is to study the role of neutrophils on the sensitivity of lymphoma cells to anti-lymphoma agents. However these methods can be generalized to study the interactions of neutrophils or neutrophil-like cells with a large range of cell types in different situations.

Neutrophils are the most abundant type of white blood cells. The isolation of neutrophils from human blood by density gradient separation method and the differentiation of human promyelocytic (HL60) cells along the granulocytic pathway are described here; to test their role on sensitivity of lymphoma cells to anti-lymphoma agents.

호중구의 분리 및 분석 치료제에 림프종 세포 감도에서 자신의 역할을 확인하는 방법

Neutrophils are the most abundant (40% to 75%) type of white blood cells and among the first inflammatory cells to migrate towards the site of ...

In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation

Acid-triggered molecular processes closely control cell entry of many viruses that enter through the endocytic system. In the case of influenza A virus (IAV), virus fusion with the endosomal membrane as well as the subsequent disassembly of the viral capsid, called uncoating, is governed by the ionic conditions inside endocytic vesicles. The early steps in the virus life cycle are hard to study because endosomes cannot be directly accessed experimentally, creating the need for an in vitro approach. Here, we describe a method based on velocity gradient centrifugation of purified virions through a two-layer glycerol gradient, which enables analysis of the IAV core and its stability. The gradient contains a non-ionic detergent (NP-40) in its lower layer to remove the viral membrane by solubilization as the virus sediments toward the bottom. At neutral pH, viral cores are pelleted as stable structures. The major core components, matrix protein (M1) and the viral ribonucleoproteins (vRNPs), can be clearly identified in the pellet fraction by SDS-PAGE. Decreasing the pH to 6.0 or lower in the bottom layer selectively removes M1 from the pellet followed by release of vRNPs at more acidic conditions. Viral protein bands on Coomassie-stained gels can be subjected to densitometric quantification to monitor intermediate states of IAV disassembly. Besides pH, other factors that influence viral core stability can be assessed, such as salt concentration and putative viral uncoating factors, simply by modifying the detergent-containing glycerol layer accordingly. Taken together, the presented technique allows highly reproducible and quantitative analysis of viral uncoating in vitro. It can be applied to other enveloped viruses that undergo complex uncoating processes.

In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation

Disassembly of influenza A virus cores during virus entry into host cells is a multistep process. We describe an in vitro method to analyze the early stages of viral uncoating. In this approach, velocity gradient centrifugation is used to biochemically dissect the steps that initiate uncoating under defined conditions.

그라데이션 원심 분리에 의해 인플루엔자 A 바이러스 캡시드의 생체 외 분해에

Acid-triggered molecular processes closely control cell entry of many viruses that enter through the endocytic system. In the case of influenza A virus ...

Influenza A Virus Studies in a Mouse Model of Infection

Influenza viruses cause over 500,000 deaths worldwide1 and are associated with an annual cost of 12 - 14 billion USD in the United States alone considering direct medical and hospitalization expenses and work absenteeism2. Animal models are crucial in Influenza A virus (IAV) studies to evaluate viral pathogenesis, host-pathogen interactions, immune responses, and the efficacy of current and/or novel vaccine approaches as well as antivirals. Mice are an advantageous small animal model because their immune system is evolutionarily similar to that found in humans, they are available from commercial vendors as genetically identical subjects, there are multiple strains that can be exploited to evaluate the genetic basis of infections, and they are relatively inexpensive and easy to manipulate. To recapitulate IAV infection in humans via the airways, mice are first anesthetized prior to intranasal inoculation with infectious IAVs under proper biosafety containment. After infection, the pathogenesis of IAVs is determined by monitoring daily the morbidity (body weight loss) and mortality (survival) rate. In addition, viral pathogenesis can also be evaluated by assessing virus replication in the upper (nasal mucosa) or lower (lungs) respiratory tract of infected mice. Humoral responses upon IAV infection can be rapidly evaluated by non-invasive bleeding and secondary antibody detection assays aimed at detecting the presence of total or neutralizing antibodies. Here, we describe the common methods used to infect mice intranasally (i.n) with IAV and evaluate pathogenesis, humoral immune responses and protection efficacy.

Influenza A viruses (IAVs) are important human respiratory pathogens. To understand the pathogenicity of IAVs and to perform preclinical testing of novel vaccine approaches, animal models mimicking human physiology are required. Here, we describe techniques to evaluate IAV pathogenesis, humoral responses and vaccine efficacy using a mouse model of infection.

감염 마우스 모델에서 인플루엔자 A 바이러스 연구

Influenza viruses cause over 500,000 deaths worldwide1 and are associated with an annual cost of 12 - 14 billion USD in the United States alone ...

Generation of Escape Variants of Neutralizing Influenza Virus Monoclonal Antibodies

Influenza viruses exhibit a remarkable ability to adapt and evade the host immune response. One way is through antigenic changes that occur on the surface glycoproteins of the virus. The generation of escape variants is a powerful method in elucidating how viruses escape immune detection and in identifying critical residues required for antibody binding. Here, we describe a protocol on how to generate influenza A virus escape variants by utilizing human or murine monoclonal antibodies (mAbs) directed against the viral hemagglutinin (HA). With the use of our technique, we previously characterized critical residues required for the binding of antibodies targeting either the head or stalk of the novel avian H7N9 HA. The protocol can be easily adapted for other virus systems. Analyses of escape variants are important for modeling antigenic drift, determining single nucleotide polymorphisms (SNPs) conferring resistance and virus fitness, and in the designing of vaccines and/or therapeutics.

We describe a method by which we identify critical residues required for the binding of human or murine monoclonal antibodies that target the viral hemagglutinin of influenza A viruses. The protocol can be adapted to other virus surface glycoproteins and their corresponding neutralizing antibodies.

인플루엔자 바이러스 단일 클론 항 체를 중화의 탈출 변종의 생성

Influenza viruses exhibit a remarkable ability to adapt and evade the host immune response. One way is through antigenic changes that occur on the surface ...