支持这项研究是由美国国立卫生研究院（NIH）的美国（RO1 AI68002）。

1。重组SARS - CoV的RBD的蛋白制备<ol><li>准备磷酸钙转染试剂<ol><li> 2X哈佛商学院的缓冲液配制：16克氯化钠，0.4克的Na 2 HPO 4 7H 2 O，13.0克HEPES混合在一起。调整pH值至7.00，并带来总量1000毫升蒸馏水中。经过过滤消毒，分装解决方案，并储存在-20 ° C 提示：任何pH值的变化会影响转染结果。因此，最好是来测试几个pH值约7.00（例如，6.99，7.00，7.01），并找到最好使用下面介绍的方法转染。 </li><li> 2.5米氯化钙2准备：在终体积为200毫升添加73.5克的氯化钙2 · 2H 2 O蒸馏水。过滤器的解决方案，并储存在-20 ° C </li></ol></li><li>重组质粒转染和蛋白的纯化<ol><li>分割前汇合24 h转染293T细胞在50-70％。成长中的T - 175厘米2组织在40毫升的DMEM含10％热灭活胎牛血清和1％青霉素/链霉素（P / S）在37 ° 5％的CO 2（HI）的彗星的培养瓶中的细胞。 </li><li>应使所有的转染试剂室温染前。这些试剂包括哈佛商学院的2倍，2.5M 氯化钙 ，DIH 2 O，和rRBD质粒6。 提示：最后的重组质粒构建用于蛋白表达，应该包含一个信号肽，以确保培养上清分泌表达的重组蛋白。可能会增加6倍His标签易于纯化的表达蛋白C -末端。 </li><li>准备之一50毫升（A）和一个15毫升（b）屋宇署猎鹰管，并加试剂如表1所示的管。 A.管B管加入2X哈佛商学院的缓冲区，加2.5M 氯化钙和rRBD质粒，并带来DIH 2 O量的要求 <table border="1"><tbody><tr><td colspan="4"> A.一个T - 175厘米2组织培养瓶（4000μL/烧瓶）：准备rRBD表达 </td></tr><tr><td colspan="2"> 管中 </td><td colspan="2"> 管B </td></tr><tr><td> 2X哈佛商学院</td><td> 2000微升</td><td> 2.5M氯化钙2 </td><td> 200微升</td></tr><tr><td></td><td></td><td> rRBD质粒DNA </td><td> 40微克</td></tr><tr><td></td><td></td><td> DIH 2 O来 </td><td> 2000微升 </td></tr><tr><td colspan="4"> B.一个100毫米的培养皿（1000μL/皿）：SARS pseudovirus生产准备</td></tr><tr><td colspan="2"> 管中 </td><td colspan="2"> 管B </td></tr><tr><td> 2X哈佛商学院</td><td> 500μL， </td><td> 2.5M氯化钙2 </td><td> 50微升</td></tr><tr><td></td><td></td><td> SARS - CoV的S质粒DNA </td><td> 5微克</td></tr><tr><td></td><td></td><td> HIV - 1质粒（pNL4 3.luc.RE） </td><td> 5微克</td></tr><tr><td></td><td></td><td> DIH 2 O来 </td><td> 500μL， </td></tr></tbody></table> 表1转染混合物制备和卷 在表1中列出的卷是一个转单位。如果更多的烧瓶或菜肴用于转染，卷相应的调整。 </li><li>添加到管中滴加方式一管B的DNA钙的解决方案，同时保持常数和温柔的一个旋涡混合。让混合物在室温下坐20-30分钟。磷酸钙转染成功的关键取决于形成的沉淀物的大小和形状。因此，应混合振荡不断，慢慢地满足这一要求，因此，提高转染疗效。 </li><li>在滴加甚至添加到293T细胞（4000微升/瓶）的混合物。培养细胞在37 ° C在5％CO2培养箱中培养。 </li><li>更换新鲜的无血清的OPTI - MEM我降低血清中（50毫升/瓶）8-10 h后转染培养液中。两个多天在相同条件下，继续培养细胞。 </li><li>收集上清含有表示rRBD蛋白72 h后转染。在15分钟6000转离心去除细胞碎片。添加蛋白酶抑制剂的鸡尾酒收集上清和储存在4 ° C过夜。 </li><li>第二天，从培养上清净化rRBD重组蛋白，用镍NTA Superflow以下制造商的指示。 </li><li>使用Amicon超-15浓度管浓缩纯化蛋白质。蛋白浓度后，添加PBS的浓度管和离心机再次删除咪唑洗脱缓冲液。计算蛋白浓度和纯化蛋白质在-80 ° C，直到使用的存储。 </li></ol></li></ol> 2。小鼠免疫及样品采集<ol><li>预温西格玛辅助系统（SAS）40-45 ° C，符合制造商的说明。加入1每ml小瓶PBS调匀。 </li><li>根据表2中的协议，准备蛋白佐剂乳化。移液器计算为1.5毫升管rRBD蛋白质。加入同等体积的SAS辅助大力为2-3分钟，以形成乳化液管和涡。 提示：在表2中列出的卷是一个鼠标。调整卷，根据实际使用的鼠标号码。对于每个组，每一种疫苗所需的蛋白质和辅助混合在一起。疫苗接种，以确保准确性，始终准备一个额外的样品。 <table border="1"><tbody><tr><td> 集团 </td><td> 第1次疫苗 （200μL/鼠标） </td><td> 第2 次疫苗 （200μL/鼠标） </td><td> 第3 次疫苗 （200μL/鼠标） </td></tr><tr><td> rRBD蛋白</td><td> 20μg蛋白在PBS （100μL）+ 100μL的SAS </td><td> 10μg蛋白在PBS（100μL）+ 100μL的SAS </td><td> 10μg蛋白在PBS（100μL）+ 100μL的SAS </td></tr><tr><td> PBS对照</td><td> 100μL的PBS + 100μL的SAS </td><td> 100μL的PBS + 100μL的SAS </td><td> 100μL的PBS + 100μL的SAS </td></tr></tbody></table> 表2。小鼠免疫协议</li><li>皮下注射免疫总理的雌性BALB / c小鼠（4-6周龄，5只/组），并加强与rRBD和SAS两次如表2所示。 PBS作为对照组。皮下注射的网站通常选择的肩胛骨之间的皮肤松弛。此外，腹部腹面是常用的，因为它更容易注入，并可能会观察到从注射部位的任何泄漏。当使用重复剂量的疫苗，它是很容易来选择不同的注射部位，防止潜在的局部皮肤反应。 </li><li>流血通过眼窝每个接种疫苗的免疫接种后10天前与麻醉剂，并在56 ° C下30分钟热血清灭活补体小鼠。商店小鼠血清于-20 ° C，直到使用。 </li></ol> 3。中和检测，​​使用Pseudovirus中和试验<ol><li>准备非典pseudovirus <ol><li> 293T细胞分裂100毫米的组织培养培养皿（2 × 10 6细胞/皿）转染前16小时，和成长细胞如上。 </li><li>准备转染试剂，如表1所示。联合转染质粒编码SARS冠状病毒S蛋白和环境保护缺陷，质粒编码荧光素酶表达的HIV - 1的基因组（pNL4 3.luc.RE）使用磷酸钙转染试剂。 </li><li>更换新鲜DMEM培养液10毫升含10％胎牛血清和1％的P / S 8-10小时后转染介质。收集上清含有非典pseudovirus 72小时后转。 </li><li>通过0.45μm滤膜过滤pseudovirus。分装和储存在-80 ° C，直到使用。 </li></ol></li><li>非典pseudovirus中和试验<ol><li>分割293T细胞表达在SARS病毒受体ACE2的（ACE2/293T）10 4 cells/100μL/孔，96孔组织培养板16小时前感染。 </li><li>稀释2倍SARS pseudovirus ACE2/293T细胞检测病毒滴度。 </li><li>串行稀释的小鼠血清中的96孔组织培养板，加等体积滴定非典pseudovirus。在37 ° C，1小时Preinc​​ubate板</li><li>孵育后，加入100μL血清pseudovirus混合ACE2/293T细胞，并继续增长，细胞在37 ° 5％的CO 2的彗星。加入新鲜的DMEM培养24 h后。 </li><li>彻底清除板从培养上清感染后72 h。添加1X荧光素酶细胞培养裂解试剂（60μL/孔），并不断摇动板在室温下1-2 h促进细胞裂解。 </li><li>转移细胞裂解液（50μL/孔）进入光度计板（Microfluor 96孔板）。加入荧光素酶检测系统中的荧光素酶底物（50微升/孔），超384光度计检测相对荧光素酶的活性。 </li><li>非典pseudovirus中和效价和目前计算为50％的中和抗体滴度（NT 50）6 。 </li></ol></li></ol>

<ol>
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细胞密度是一个重要因素，影响磷酸钙为基础的转的疗效。根据我们的经验，低于70％的细胞汇合带来最好的结果。因此，为了提高转染效率，建议保持在约50-70％汇合，细胞密度。磷酸钙转染法一般被认为与其他转染方法，如脂质转染16相比，效率较低。然而，在这个协议中，我们使用一个修改过的磷酸钙转染法，即常数和慢转的解决方案中的一个旋涡混合确保适当的大小和形状形成沉淀，从而提高转染效率。

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>NaCl</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>S7653</td>
<td>&nbsp;</td>
<tr>
<td>Na2HPO4*7H2O</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>S2429</td>
<td>&nbsp;</td>
<tr>
<td>HEPES</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>H3375</td>
<td>&nbsp;</td>
<tr>
<td>CaCl2*2H2O</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>C5080</td>
<td>&nbsp;</td>
<tr>
<td>DMEM</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>12430</td>
<td>&nbsp;</td>
<tr>
<td>HI FBS</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>10438</td>
<td>&nbsp;</td>
<tr>
<td>Penicillin/Streptomycin</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>15140</td>
<td>&nbsp;</td>
<tr>
<td>OPTI-MEM I Medium</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>31985</td>
<td>&nbsp;</td>
<tr>
<td>Protease inhibitor cocktail</td>
<td>&nbsp;</td>
<td>Roche</td>
<td>11836170001</td>
<td>&nbsp;</td>
<tr>
<td>Ni-NTA Superflow</td>
<td>&nbsp;</td>
<td>Qiagen</td>
<td>30450</td>
<td>&nbsp;</td>
<tr>
<td>Sigma adjuvant system</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>S6322</td>
<td>&nbsp;</td>
<tr>
<td>Luciferase assay system</td>
<td>&nbsp;</td>
<td>Promega</td>
<td>E1501</td>
<td>&nbsp;</td>
<tr>
<td>Luciferase cell culture lysis reagent (5X)</td>
<td>&nbsp;</td>
<td>Promega</td>
<td>E1531</td>
<td>&nbsp;</td>
<tr>
<td>Amicon Ultra - 15</td>
<td>&nbsp;</td>
<td>Millipore</td>
<td>UFC901024</td>
<td>&nbsp;</td>
<tr>
<td>Microfluor 96-well plates</td>
<td>&nbsp;</td>
<td>Thermo Scientific</td>
<td>7905</td>
<td>&nbsp;</td>
<tr>
<td>Ultra 384 luminometer</td>
<td>&nbsp;</td>
<td>Tecan Systems</td>
<td>&nbsp;</td>
<td>&nbsp;</td>		</tbody>
		</table>
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protocol for recombinant rbd-based sars vaccines: protein preparation, animal vaccination and neutralization detection

基于其安全性和诱导抗感染的免疫反应的能力，亚单位疫苗已被用来作为候选人为多种病原体 1-3 。由于哺乳动物细胞系统的能力，从而形成正确折叠和糖基化蛋白质翻译后修饰，在哺乳动物细胞中表达的重组蛋白都表现出了极大的潜力，以保持较高的抗原性和免疫原性4-6。 自2004年以来，虽然没有发现新病例的SARS疫情的是一个恒定的威胁，因此，对SARS冠状病毒疫苗的发展是一个审慎的预防的步骤，并应进行。 RBD的SARS - CoV的S蛋白在受体结合，诱导特异性中和抗体对病毒感染7-9扮演重要的角色。因此，在这个协议中，我们描述发展RBD的亚单位疫苗，对SARS的新方法。简单地说，RBD的重组蛋白（rRBD）在培养的哺乳动物293T细胞培养上清表示，获得正确的构型和高免疫原性6正确折叠的蛋白质。的RBD的重组质粒转染的细胞，然后使用一些修改一个磷酸钙转染法6,10。 11,12与脂质转染法相比，这个修改过的磷酸钙转染法是更便宜，更容易处理，有可能达到疗效高，一旦形成一个合适的大小和形状的转复杂13,14。最后，在协议中引入综合症pseudovirus中和试验，用于检测rRBD蛋白免疫小鼠血清中和活性。此实验是比较安全的，不涉及传染性的SARS冠状病毒，并可以不执行了一个生物安全实验室 15的要求。 这里所描述的协议也可以用来设计和研究I类融合蛋白的重组亚单位疫苗，对其他病毒，例如，艾滋病毒，呼吸道合胞病毒（RSV），埃博拉病毒，流感病毒，以及尼帕和Handra病毒。此外，产生pseudovirus和随后建立pseudovirus中和试验方法可以适用于所有这些病毒。

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Protocol for Recombinant RBD-based SARS Vaccines: Protein Preparation, Animal Vaccination and Neutralization Detection

这一协议描述为抗击非典研究重组受体结合域（RBD）为基础的亚单位疫苗的一般程序。它包括RBD的蛋白在293T细胞中，免疫与RBD的小鼠，检测小鼠血清中和使用建立非典pseudovirus中和试验活动的转染和表达方法。

协议RBD - SARS疫苗的重组蛋白的制备，动物疫苗接种和中检测

Based on their safety profile and ability to induce potent immune responses against infections, subunit vaccines have been used as candidates for a wide ...

protocol-for-recombinant-rbd-based-sars-vaccines-protein-preparation

Research

JoVE Journal

Immunology and Infection

42.4K 次观看.  New York Blood Center.  中文 

视频: Protocol for Recombinant RBD-based SARS Vaccines: Protein Preparation, Animal Vaccination and Neutralization Detection

Combination of Adhesive-tape-based Sampling and Fluorescence in situ Hybridization for Rapid Detection of Salmonella on Fresh Produce

This protocol describes a simple approach for adhesive-tape-based sampling of tomato and other fresh produce surfaces, followed by on-tape fluorescence in situ hybridization (FISH) for rapid culture-independent detection of Salmonella spp. Cell-charged tapes can also be placed face-down on selective agar for solid-phase enrichment prior to detection. Alternatively, low-volume liquid enrichments (liquid surface miniculture) can be performed on the surface of the tape in non-selective broth, followed by FISH and analysis via flow cytometry. To begin, sterile adhesive tape is brought into contact with fresh produce, gentle pressure is applied, and the tape is removed, physically extracting microbes present on these surfaces. Tapes are mounted sticky-side up onto glass microscope slides and the sampled cells are fixed with 10% formalin (30 min) and dehydrated using a graded ethanol series (50, 80, and 95%; 3 min each concentration). Next, cell-charged tapes are spotted with buffer containing a Salmonella-targeted DNA probe cocktail and hybridized for 15 - 30 min at 55&deg;C, followed by a brief rinse in a washing buffer to remove unbound probe. Adherent, FISH-labeled cells are then counterstained with the DNA dye 4',6-diamidino-2-phenylindole (DAPI) and results are viewed using fluorescence microscopy. For solid-phase enrichment, cell-charged tapes are placed face-down on a suitable selective agar surface and incubated to allow in situ growth of Salmonella microcolonies, followed by FISH and microscopy as described above. For liquid surface miniculture, cell-charged tapes are placed sticky side up and a silicone perfusion chamber is applied so that the tape and microscope slide form the bottom of a water-tight chamber into which a small volume (&le; 500 &mu;L) of Trypticase Soy Broth (TSB) is introduced. The inlet ports are sealed and the chambers are incubated at 35 - 37&deg;C, allowing growth-based amplification of tape-extracted microbes. Following incubation, inlet ports are unsealed, cells are detached and mixed with vigorous back and forth pipetting, harvested via centrifugation and fixed in 10% neutral buffered formalin. Finally, samples are hybridized and examined via flow cytometry to reveal the presence of Salmonella spp. As described here, our "tape-FISH" approach can provide simple and rapid sampling and detection of Salmonella on tomato surfaces. We have also used this approach for sampling other types of fresh produce, including spinach and jalape&ntilde;o peppers.

Combination of Adhesive-tape-based Sampling and Fluorescence in situ Hybridization for Rapid Detection of Salmonella on Fresh Produce

This protocol describes a simple adhesive-tape-based approach for sampling of tomato and other fresh produce surfaces, followed by rapid whole cell detection of Salmonella using fluorescence in situ hybridization (FISH).

胶粘剂基于磁带的采样和荧光组合原位杂交快速检测沙门氏菌新鲜农产品

This protocol describes a simple approach for adhesive-tape-based sampling of tomato and other fresh produce surfaces, followed by on-tape fluorescence in ...

科研

免疫与感染

Whole-animal Imaging and Flow Cytometric Techniques for Analysis of Antigen-specific CD8+ T Cell Responses after Nanoparticle Vaccination

Traditional vaccine adjuvants, such as alum, elicit suboptimal CD8+ T cell responses. To address this major challenge in vaccine development, various nanoparticle systems have been engineered to mimic features of pathogens to improve antigen delivery to draining lymph nodes and increase antigen uptake by antigen-presenting cells, leading to new vaccine formulations optimized for induction of antigen-specific CD8+ T cell responses. In this article, we describe the synthesis of a &#8220;pathogen-mimicking&#8221; nanoparticle system, termed interbilayer-crosslinked multilamellar vesicles (ICMVs) that can serve as an effective vaccine carrier for co-delivery of subunit antigens and immunostimulatory agents and elicitation of potent cytotoxic CD8+ T lymphocyte (CTL) responses. We describe methods for characterizing hydrodynamic size and surface charge of vaccine nanoparticles with dynamic light scattering and zeta potential analyzer and present a confocal microscopy-based procedure to analyze nanoparticle-mediated antigen delivery to draining lymph nodes. Furthermore, we show a new bioluminescence whole-animal imaging technique utilizing adoptive transfer of luciferase-expressing, antigen-specific CD8+ T cells into recipient mice, followed by nanoparticle vaccination, which permits non-invasive interrogation of expansion and trafficking patterns of CTLs in real time. We also describe tetramer staining and flow cytometric analysis of peripheral blood mononuclear cells for longitudinal quantification of endogenous T cell responses in mice vaccinated with nanoparticles.

We describe whole-animal imaging and flow cytometry-based techniques for monitoring expansion of antigen-specific CD8+ T cells in response to immunization with nanoparticles in a murine model of vaccination.

对于纳米颗粒疫苗接种后的分析抗原特异性CD8 + T细胞应答整体动物成像和流式细胞技术

Traditional vaccine adjuvants, such as alum, elicit suboptimal CD8+ T cell responses. To address this major challenge in vaccine development, various ...

Intranasal Administration of Recombinant Influenza Vaccines in Chimeric Mouse Models to Study Mucosal Immunity

Vaccines are one of the greatest achievements of mankind, and have saved millions of lives over the last century. Paradoxically, little is known about the physiological mechanisms that mediate immune responses to vaccines perhaps due to the overall success of vaccination, which has reduced interest into the molecular and physiological mechanisms of vaccine immunity. However, several important human pathogens including influenza virus still pose a challenge for vaccination, and may benefit from immune-based strategies. 
Although influenza reverse genetics has been successfully applied to the generation of live-attenuated influenza vaccines (LAIVs), the addition of molecular tools in vaccine preparations such as tracer components to follow up the kinetics of vaccination in vivo, has not been addressed. In addition, the recent generation of mouse models that allow specific depletion of leukocytes during kinetic studies has opened a window of opportunity to understand the basic immune mechanisms underlying vaccine-elicited protection. Here, we describe how the combination of reverse genetics and chimeric mouse models may help to provide new insights into how vaccines work at physiological and molecular levels, using as example a recombinant, cold-adapted, live-attenuated influenza vaccine (LAIV). We utilized laboratory-generated LAIVs harboring cell tracers as well as competitive bone marrow chimeras (BMCs) to determine the early kinetics of vaccine immunity and the main physiological mechanisms responsible for the initiation of vaccine-specific adaptive immunity. In addition, we show how this technique may facilitate gene function studies in single animals during immune responses to vaccines. We propose that this technique can be applied to improve current prophylactic strategies against pathogens for which urgent medical countermeasures are needed, for example influenza, HIV, Plasmodium, and hemorrhagic fever viruses such as Ebola virus.

There is an overall lack of knowledge about how vaccines work. Here we propose the combined use of reverse genetics and bone marrow chimeric mice to gain insight into the early host immune responses to vaccines with a special focus on dendritic cells and T cell immunity.

重组流感疫苗的嵌合体小鼠模型鼻腔给药研究黏膜免疫

Vaccines are one of the greatest achievements of mankind, and have saved millions of lives over the last century. Paradoxically, little is known about the ...

In Vivo Assay for Detection of Antigen-specific T-cell Cytolytic Function Using a Vaccination Model

Current methodologies for antigen-specific killing are limited to in vitro use or utilized in infectious disease models. However, there is not a protocol specifically intended to measure antigen-specific killing without an infection. This protocol is designed and describes methods to overcome these limitations by allowing for the detection of antigen-specific killing of a target cell by CD8+ T cells in vivo. This is accomplished by merging a vaccination model with a traditional CFSE-labeled target killing assay. This combination allows the researcher to assess the antigen-specific CTL potential directly and quickly as the assay is not dependent upon tumor growth or infection. In addition, the readout is based on flow cytometry and so should be readily accessible to most researchers. The major limitation of the study is identifying the timeline in vivo that is appropriate to the hypothesis being tested. Variations in antigen strength and mutations in the T cells that may result in differential cytolytic function need to be carefully assessed to determine the optimal time for cell harvest and assessment. The appropriate concentration of peptide for vaccination has been optimized for hgp10025-33 and OVA257-264, but further validation would be needed for other peptides that may be more appropriate to a given study. Overall, this protocol allows a quick assessment of killing function in vivo and can be adapted to any given antigen.

In Vivo Assay for Detection of Antigen-specific T-cell Cytolytic Function Using a Vaccination Model

The goal of this protocol is to allow for detection of in vivo antigen-specific killing of a target cell in a murine model.

在体内应用免疫模型检测抗原特异性 T 细胞细胞功能的试验

Current methodologies for antigen-specific killing are limited to in vitro use or utilized in infectious disease models. However, there is not a protocol ...

Generating Recombinant Avian Herpesvirus Vectors with CRISPR/Cas9 Gene Editing

Herpesvirus of turkeys (HVT) is an ideal viral vector for the generation of recombinant vaccines against a number of avian diseases, such as avian influenza (AI), Newcastle disease (ND), and infectious bursal disease (IBD), using bacterial artificial chromosome (BAC) mutagenesis or conventional recombination methods. The clustered regularly interspaced palindromic repeats (CRISPR)/Cas9 system has been successfully used in many settings for gene editing, including the manipulation of several large DNA virus genomes. We have developed a rapid and efficient CRISPR/Cas9-mediated genome editing pipeline to generate recombinant HVT. To maximize the potential use of this method, we present here detailed information about the methodology of generating recombinant HVT expressing the VP2 protein of IBDV. The VP2 expression cassette is inserted into the HVT genome via an NHEJ (nonhomologous end-joining)-dependent repair pathway. A green fluorescence protein (GFP) expression cassette is first attached to the insert for easy visualization and then removed via the Cre-LoxP system. This approach offers an efficient way to introduce other viral antigens into the HVT genome for the rapid development of recombinant vaccines.

Herpesvirus of turkeys (HVT) is widely used as a vector platform for the generation of recombinant vaccines against a number of avian diseases. This article describes a simple and rapid approach for the generation of recombinant HVT-vectored vaccines using an integrated NHEJ-CRISPR/Cas9 and Cre-Lox system.

用 crispr/cas9 基因编辑生成重组禽流感病毒载体

Herpesvirus of turkeys (HVT) is an ideal viral vector for the generation of recombinant vaccines against a number of avian diseases, such as avian ...

Analysis of Iophenoxic Acid Analogues in Small Indian Mongoose (Herpestes Auropunctatus) Sera for Use as an Oral Rabies Vaccination Biological Marker

The small Indian mongoose (Herpestes auropunctatus) is a reservoir of rabies virus (RABV) in Puerto Rico and comprises over 70% of animal rabies cases reported annually. The control of RABV circulation in wildlife reservoirs is typically accomplished by a strategy of oral rabies vaccination (ORV). Currently no wildlife ORV program exists in Puerto Rico. Research into oral rabies vaccines and various bait types for mongooses has been conducted with promising results. Monitoring the success of ORV relies on estimating bait uptake by target species, which typically involves evaluating a change in RABV neutralizing antibodies (RVNA) post vaccination. This strategy may be difficult to interpret in areas with an active wildlife ORV program or in areas where RABV is enzootic and background levels of RVNA are present in reservoir species. In such situations, a biomarker incorporated with the vaccine or the bait matrix may be useful. We offered 16 captive mongooses placebo ORV baits containing ethyl-iophenoxic acid (et-IPA) in concentrations of 0.4% and 1% inside the bait and 0.14% in the external bait matrix. We also offered 12 captive mongooses ORV baits containing methyl-iophenoxic acid (me-IPA) in concentrations of 0.035%, 0.07% and 0.14% in the external bait matrix. We collected a serum sample prior to bait offering and then weekly for up to eight weeks post offering. We extracted Iophenoxic acids from sera into acetonitrile and quantified using liquid chromatography/mass spectrometry. We analyzed sera for et-IPA or me-IPA by liquid chromatography-mass spectrometry. We found adequate marking ability for at least eight and four weeks for et- and me-IPA, respectively. Both IPA derivatives could be suitable for field evaluation of ORV bait uptake in mongooses. Due to the longevity of the marker in mongoose sera, care must be taken to not confound results by using the same IPA derivative during consecutive evaluations.

Analysis of Iophenoxic Acid Analogues in Small Indian Mongoose Herpestes Auropunctatus Sera for Use as an Oral Rabies Vaccination Biological Marker

We offered captive mongooses placebo oral rabies vaccine baits with ethyl or methyl iophenoxic acid as a biomarker and verified bait uptake using a novel liquid chromatography with tandem mass spectrometry (LC-MS/MS) method.

小印度蒙古狼的异苯抗酸模拟分析(赫皮斯特奥罗普塔图斯)塞拉,用作口服狂犬病疫苗接种生物标记

The small Indian mongoose (Herpestes auropunctatus) is a reservoir of rabies virus (RABV) in Puerto Rico and comprises over 70% of animal rabies cases ...

A Rapid, Multiplex Dual Reporter IgG and IgM SARS-CoV-2 Neutralization Assay for a Multiplexed Bead-Based Flow Analysis System

The COVID-19 pandemic has underscored the need for rapid high-throughput methods for sensitive and specific serological detection of infection with novel pathogens, such as SARS-CoV-2. Multiplex serological testing can be particularly useful because it can simultaneously analyze antibodies to multiple antigens that optimizes pathogen coverage, and controls for variability in the organism and the individual host response. Here we describe a SARS-CoV-2 IgG 3-plex fluorescent microsphere-based assay that can detect both IgM and IgG antibodies to three major SARS-CoV-2 antigens-the spike (S) protein, spike angiotensin-converting enzyme-2 (ACE2) receptor-binding domain (RBD), and nucleocapsid (Nc). The assay was shown to have comparable performance to a SARS-CoV-2 reference assay for IgG in serum obtained at &#8805;21 days from symptom onset but had higher sensitivity with samples collected at &#8804;5 days from symptom onset. Further, using soluble ACE2 in a neutralization assay format, inhibition of antibody binding was demonstrated for S and RBD.

A flow analysis system for bead-based multiplexed assays which provides a two-reporter readout was used for the development of multiplex serological and antibody neutralization assays that can simultaneously measure neutralizing IgG and IgM antibodies for SARS-CoV-2.

基于多路复用珠子的流量分析系统的快速、多路双记者 IgG 和 Igm SARS-CoV-2 中和检测

The COVID-19 pandemic has underscored the need for rapid high-throughput methods for sensitive and specific serological detection of infection with novel ...

Detection of SARS-CoV-2 Receptor-Binding Domain Antibody using a HiBiT-Based Bioreporter

The emergence of the COVID-19 pandemic has increased the need for better serological detection methods to determine the epidemiologic impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The increasing number of SARS-CoV-2 infections raises the need for better antibody detection assays. Current antibody detection methods compromise sensitivity for speed or are sensitive but time-consuming. A large proportion of SARS-CoV-2-neutralizing antibodies target the receptor-binding domain (RBD), one of the primary immunogenic compartments of SARS-CoV-2. We have recently designed and developed a highly sensitive, bioluminescent-tagged RBD (NanoLuc HiBiT-RBD) to detect SARS-CoV-2 antibodies. The following text describes the procedure to produce the HiBiT-RBD complex and a fast assay to evaluate the presence of RBD-targeting antibodies using this tool. Due to the durability of the HiBiT-RBD protein product over a wide range of temperatures and the shorter experimental procedure that can be completed within 1 h, the protocol can be considered as a more efficient alternative to detect SARS-CoV-2 antibodies in patient serum samples.

The outlined protocol describes the procedure for producing the HiBiT-receptor-binding domain protein complex and its application for fast and sensitive detection of SARS-CoV-2 antibodies.

使用基于HiBiT的生物报告器检测SARS-CoV-2受体结合域抗体

The emergence of the COVID-19 pandemic has increased the need for better serological detection methods to determine the epidemiologic impact of severe ...

Live Imaging and Quantification of Viral Infection in K18 hACE2 Transgenic Mice Using Reporter-Expressing Recombinant SARS-CoV-2

The coronavirus disease 2019 (COVID-19) pandemic has been caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To date, SARS-CoV-2 has been responsible for over 242 million infections and more than 4.9 million deaths worldwide. Similar to other viruses, studying SARS-CoV-2 requires the use of experimental methods to detect the presence of virus in infected cells and/or in animal models. To overcome this limitation, we generated replication-competent recombinant (r)SARS-CoV-2 that expresses bioluminescent (nanoluciferase, Nluc) or fluorescent (Venus) proteins. These reporter-expressing rSARS-CoV-2 allow tracking viral infections in vitro and in vivo based on the expression of Nluc and Venus reporter genes. Here the study describes the use of rSARS-CoV-2/Nluc and rSARS-CoV-2/Venus to detect and track SARS-CoV-2 infection in the previously described K18 human angiotensin-converting enzyme 2 (hACE2) transgenic mouse model of infection using in vivo imaging systems (IVIS). This rSARS-CoV-2/Nluc and rSARS-CoV-2/Venus show rSARS-CoV-2/WT-like pathogenicity and viral replication in vivo. Importantly, Nluc and Venus expression allow us to directly track viral infections in vivo and ex vivo, in infected mice. These rSARS-CoV-2/Nluc and rSARS-CoV-2/Venus represent an excellent option to study the biology of SARS-CoV-2 in vivo, to understand viral infection and associated COVID-19 disease, and to identify effective prophylactic and/or therapeutic treatments to combat SARS-CoV-2 infection.

This protocol describes the dynamics of viral infections using luciferase- and fluorescence-expressing recombinant (r)SARS-CoV-2 and an in vivo imaging systems (IVIS) in K18 hACE2 transgenic mice to overcome the need of secondary approaches required to study SARS-CoV-2 infections in vivo.

使用报告基因表达重组SARS-CoV-2对K18 hACE2转基因小鼠的病毒感染进行实时成像和定量

The coronavirus disease 2019 (COVID-19) pandemic has been caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To date, SARS-CoV-2 has ...

Detection of Neutralization-sensitive Epitopes in Antigens Displayed on Virus-Like Particle (VLP)-Based Vaccines Using a Capture Assay

The virus-like particle (VLP) capture assay is an immunoprecipitation method, commonly known as a &#39;pull-down assay&#39; used to purify and isolate antigen-displaying VLPs. Surface antigen-specific antibodies are coupled to, and thus immobilized on a solid and insoluble matrix such as beads. Due to their high affinity to the target antigen, these antibodies can capture VLPs decorated with the cognate antigen anchored in the membrane envelope of the VLPs. This protocol describes the binding of antigen-specific antibodies to protein A- or G-conjugated magnetic beads. In our study, human immunodeficiency virus (HIV)-derived VLPs formed by the group-specific antigen (Gag) viral core precursor protein p55 Gag and displaying the envelope glycoproteins (Env) of HIV are examined. The VLPs are captured utilizing broadly neutralizing antibodies (bNAbs) directed against neutralization-sensitive epitopes in Env. The VLP capture assay outlined here represents a sensitive and easy-to-perform method to demonstrate that (i) the VLPs are decorated with the respective target antigen, (ii) the surface antigen retained its structural integrity as demonstrated by the epitope-specific binding of bNAbs used in the assay and (iii) the structural integrity of the VLPs revealed by the detection of Gag proteins in a subsequent Western blot-analysis. Consequently, the utilization of bNAbs for immunoprecipitation facilitates a prediction of whether VLP vaccines will be able to elicit a neutralizing B cell response in vaccinated humans. We anticipate that this protocol will furnish other researchers with a valuable and straightforward experimental approach to examine potential VLP-based vaccines.

Detection of Neutralization-sensitive Epitopes in Antigens Displayed on Virus-Like Particle VLP-Based Vaccines Using a Capture Assay

Here, we present a protocol to detect neutralization epitopes on antigen-displaying virus-like particles (VLPs). Immunoprecipitation of the human immunodeficiency virus (HIV)-derived VLPs is performed using envelope glycoproteins-specific monoclonal antibodies coupled to protein G-conjugated magnetic beads. Captured VLPs are subsequently subjected to SDS-PAGE and Western blot-analysis employing viral core protein Gag-specific antibodies.

使用捕获测定法检测基于病毒样颗粒（VLP）的疫苗上显示的抗原中和敏感表位

The virus-like particle (VLP) capture assay is an immunoprecipitation method, commonly known as a &#39;pull-down assay&#39; used to purify and isolate ...