المؤلفون ممتنون لايسن H. ، Gubbels M. ، K. غرينسفن فان ، جوين E. ، دريك A. ، V. ماهاجان ، قاو م ، وغ ياب لإجراء مناقشات مثمرة والكواشف. ونحن ممتنون لDausman J. ، R. فلانري ، وجيه جاكسون للحصول على المساعدة في إدارة المستعمرة الماوس. ونحن ممتنون لWisniewski P. للFACSorting. كان مدعوما من قبل برنامج EMF العلوم الإنسانية حدود. وأيد RJ بواسطة المعهد الوطني للصحة منح RO1 - R37 HD045022 وCA084198. وأيد HLP من المنح المقدمة من المعهد الوطني للصحة.

<ol>
	<li>Schatz, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=V(D)J+recombination.">V(D)J recombination.</a> Immunol. Rev. 200, 5-5 (2004).</li><li>Barnden, M. J., Allison, J., Heath, W. R., Carbone, F. R., R, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Defective+TCR+expression+in+transgenic+mice+constructed+using+cDNA-based+alpha-+and+beta-chain+genes+under+the+control+of+heterologous+regulatory+elements.">Defective TCR expression in transgenic mice constructed using cDNA-based alpha- and beta-chain genes under the control of heterologous regulatory elements.</a> Immunol. Cell Biol. 76, 34-34 (1998).</li><li>Eggan, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hybrid+vigor,+fetal+overgrowth,+and+viability+of+mice+derived+by+nuclear+cloning+and+tetraploid+embryo+complementation.">Hybrid vigor, fetal overgrowth, and viability of mice derived by nuclear cloning and tetraploid embryo complementation.</a> Proc Natl Acad Sci U S A. 98, 6209-6209 (2001).</li><li>Kishigami, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Significant+improvement+of+mouse+cloning+technique+by+treatment+with+trichostatin+A+after+somatic+nuclear+transfer.">Significant improvement of mouse cloning technique by treatment with trichostatin A after somatic nuclear transfer.</a> Biochem Biophys Res Commun. 340, 183-183 (2006).</li><li>Wakayama, T., Yanagimachi, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+cloning+with+nucleus+donor+cells+of+different+age+and+type.">Mouse cloning with nucleus donor cells of different age and type.</a> Mol Reprod Dev. 58, 376-376 (2001).</li></ol>

وقد تم رفعها على براءة اختراع.

وقد أظهرت لنا هنا والتي يمكن استخدامها لتوليد فئران SCNT transnuclear من الخلايا التائية مع خصوصية محددة مسبقا. وإن لم يكن هو موضح هنا ، ينبغي أن تكون أيضا قابلة للاستخدام تقنية لتوليد الفئران من خلايا B transnuclear مع خصوصية محددة مسبقا. شيء واحد مهم هو أن تنظر إلى السلالة والجنس من الماوس ، والذي هو مصاب أو تحصين وتستخدم لعزل الخلايا T أو B من الفائدة. منذ خلايا T و B لديها كفاءة منخفضة للغاية في برمجة عامة ، فإننا نوصي باستخدام الهجينة F1 من النمط الفرداني المطلوب. لأن الخلية المانحة ، كما يحدد الجنس ، ونحن نوصي باستخدام خلايا T أو B من الفئران الذكور. وهذا يعني أن الفئران الذكور فقط خيالية سيحيل TCR BCR أو من خلال germline ، مع الفئران الذكور يجري أسهل وأسرع لتكاثرها. أخذت معا ، ونحن نعتقد أن إعادة برمجة جينية عبر SCNT يمثل أداة قوية لتوليد نوع جديد من نماذج الماوس ، والتي سوف تكون له ميزة كبيرة للحقل المناعية.

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<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">	
		
		<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>Red Blood Cell lysis Buffer</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>R7757</td>
<td>&nbsp;</td>
<tr>
<td>Cell strainer</td>
<td>&nbsp;</td>
<td>BD Falcon</td>
<td>REF 352340</td>
<td>&nbsp;</td>
<tr>
<td>Pregnant Mare Serum (PMS)</td>
<td>&nbsp;</td>
<td>Calbiochem</td>
<td>367222</td>
<td>&nbsp;</td>
<tr>
<td>Human Chorionic Gonadotropin (HCG)</td>
<td>&nbsp;</td>
<td>Calbiochem</td>
<td>230734</td>
<td>&nbsp;</td>
<tr>
<td>Hyaluronidase</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>H4272</td>
<td>Type IV-S</td>
</tr>
<tr>
<td>KSOM-AA</td>
<td>&nbsp;</td>
<td>Millipore</td>
<td>MR-106-D</td>
<td>&nbsp;</td>
<tr>
<td>HCZB</td>
<td>&nbsp;</td>
<td>Millipore</td>
<td>MR-173-D</td>
<td>Customized medium</td>
</tr>
<tr>
<td>Ca-free medium for activation</td>
<td>&nbsp;</td>
<td>Millipore</td>
<td>MR-174-D</td>
<td>Customized medium</td>
</tr>
<tr>
<td>SrCl2</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>255521</td>
<td>100mM = 10x</td>
</tr>
<tr>
<td>AlbuMAX I</td>
<td>&nbsp;</td>
<td>Gibco</td>
<td>11020-021</td>
<td>&nbsp;</td>
<tr>
<td>PVP</td>
<td>&nbsp;</td>
<td>MP Biotech</td>
<td>102787</td>
<td>Make 10% solution using HCZB, and add 0.1% AlbuMAX I</td>
</tr>
<tr>
<td>Cytochalasin B</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>C6762</td>
<td>500&mu;g/ml = 100x</td>
</tr>
<tr>
<td>Trichostatin A</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>T8552</td>
<td>5mM = 1000x</td>
</tr>
<tr>
<td>Mineral Oil</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>M5310</td>
<td>&nbsp;</td>
<tr>
<td>Holding needle</td>
<td>&nbsp;</td>
<td>Humagen</td>
<td>MPH-SM-30</td>
<td>&nbsp;</td>
<tr>
<td>Injection and transfer needles</td>
<td>&nbsp;</td>
<td>Humagen</td>
<td>4-15, 7-15, 15-15</td>
<td>&nbsp;</td>
<tr>
<td>Mouth pipette</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>A5177</td>
<td>&nbsp;</td>
<tr>
<td>Scissors</td>
<td>&nbsp;</td>
<td>Fine Science Instruments</td>
<td>14088-10</td>
<td>or something similar</td>
</tr>
<tr>
<td>Forceps</td>
<td>&nbsp;</td>
<td>Fine Science Instruments</td>
<td>11251-10</td>
<td>or something similar</td>
</tr>
<tr>
<td>Wound Clip Applicator</td>
<td>&nbsp;</td>
<td>BD</td>
<td>427630</td>
<td>&nbsp;</td>
<tr>
<td>Wound Clips</td>
<td>&nbsp;</td>
<td>BD</td>
<td>427630</td>
<td>&nbsp;</td>
<tr>
<td>Suture</td>
<td>&nbsp;</td>
<td>Ethicon</td>
<td>K871H</td>
<td>&nbsp;</td>
<tr>
<td>DMEM</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>D6429</td>
<td>&nbsp;</td>
<tr>
<td>FBS</td>
<td>&nbsp;</td>
<td>Hyclone</td>
<td>SH30071.03</td>
<td>15%</td>
</tr>
<tr>
<td>Penicillin/Streptomycin</td>
<td>&nbsp;</td>
<td>Lonza</td>
<td>17-602E</td>
<td>100x</td>
</tr>
<tr>
<td>Glutamin</td>
<td>&nbsp;</td>
<td>MP Biomedicals</td>
<td>101806</td>
<td>200mM = 100x</td>
</tr>
<tr>
<td>Non-essential Aminoacids</td>
<td>&nbsp;</td>
<td>Gibco</td>
<td>11140050</td>
<td>100x</td>
</tr>
<tr>
<td>&beta;-Mercaptoethanol</td>
<td>&nbsp;</td>
<td>Gibco</td>
<td>21985-023</td>
<td>5&mu;l in 500ml</td>
</tr>
<tr>
<td>LIF</td>
<td>&nbsp;</td>
<td>Millipore</td>
<td>ESG1106</td>
<td>1000x</td>
</tr>
<tr>
<td>MEK inhibitor</td>
<td>&nbsp;</td>
<td>Cell Signaling</td>
<td>9900L</td>
<td>For ES derivation only, add to ES medium (final concentration 50&mu;M)</td>
</tr>		</tbody>
		</table>
		</div>

transnuclear mice with pre-defined t cell receptor specificities against toxoplasma gondii obtained via scnt

اللمفاويات ، مثل خلايا T ، الخضوع الجينية V تأشب J (D) ، لتوليد مستقبلات مع خصوصية معينة 1. المعدلة وراثيا عن الفئران ترتيبها مستضد محددة مستقبلات الخلايا التائية (TCR) تم أداة لا غنى عنها لدراسة تطور الخلايا T وظيفة. ومع ذلك ، عادة ما يتم عزل هذه TCRs من خلايا تي ذات الصلة بعد فترة طويلة الأجل ثقافة التالية غالبا تحفيز المستضد المتكررة ، التي لا مفر منها لتحديد الخلايا التائية مع تقارب عالية. التكامل الجينومية عشوائية من TCR α β وسلسلة والتعبير ، من غير الذاتية المروجين يمكن أن تؤدي إلى اختلافات في مستوى التعبير وحركية. إعادة برمجة جينية عبر نقل نواة الخلية الجسدية ويوفر أداة لتوليد الخلايا الجذعية الجنينية والفئران من أي خلية من الاهتمام. وبالتالي ، عندما يتم تطبيق SCNT لخلايا تي من التحديد المعروف ، يتم نقل هذه الجينية V (D) لإعادة ترتيب J الخلايا الجذعية الجنينية SCNT - (المجالس) والفئران المستمدة منها ، في حين يتم إعادة تعيين علامات جينية. لقد أظهرنا أنه يمكن استخدام خلايا T مع خصوصيات محددة مسبقا ضد التوكسوبلازما الغوندية لتوليد نماذج الماوس التي تعبر عن TCR مواضع محددة من الذاتية الخاصة بهم ، من دون التعديل الوراثي قدم تجريبيا. السهولة النسبية والسرعة التي يمكن الحصول على نماذج من هذا القبيل transnuclear يبشر بالخير لبناء نماذج الأمراض الأخرى.

Watch this Scientific Journal Video about Transnuclear Mice with Pre-defined T Cell Receptor Specificities Against Toxoplasma gondii Obtained Via SCNT at JoVE.com

Transnuclear Mice with Pre-defined T Cell Receptor Specificities Against Toxoplasma gondii Obtained Via SCNT

نظهر هنا التي يمكن استخدامها عبر إعادة برمجة جينية نقل نواة الخلية الجسدية (SCNT) بوصفه أداة لتوليد نماذج الفأر مع محددة مسبقا مستقبلات الخلايا التائية (TCR) الخصوصيات. هذه الفئران transnuclear تعبر عن TCR المقابلة من موضع الذاتية الخاصة بهم تحت سيطرة المروج المحلية.

Transnuclear الفئران مع الخصوصيات المحددة مسبقا ضد مستقبلات الخلايا T المقوسة الغوندية الحصول عليها عن طريق SCNT

Lymphocytes, such as T cells, undergo genetic V(D)J recombination, to generate a receptor with a certain specificity1. Mice transgenic for a rearranged ...

transnuclear-mice-with-pre-defined-t-cell-receptor-specificities

Research

JoVE Journal

Immunology and Infection

Transnuclear Mice with Pre-defined T Cell Receptor Specificities Against Toxoplasma gondii Obtained Via SCNT

14.0K Views.  Whitehead Institute for Biomedical Research. نظهر هنا التي يمكن استخدامها عبر إعادة برمجة جينية نقل نواة الخلية الجسدية (SCNT) بوصفه أداة لتوليد نماذج الفأر مع محددة مسبقا مستقبلات الخلايا التائية (TCR) الخصوصيات. هذه الفئران transnuclear تعبر عن TCR المقابلة من موضع الذاتية الخاصة بهم تحت سيطرة المروج المحلية.

Video: Transnuclear Mice with Pre-defined T Cell Receptor Specificities Against Toxoplasma gondii Obtained Via SCNT

Obtaining Highly Purified Toxoplasma gondii Oocysts by a Discontinuous Cesium Chloride Gradient

Toxoplasma gondii is an obligate intracellular protozoan pathogen that commonly infects humans. It is a well characterized apicomplexan associated with causing food- and water-borne disease outbreaks. The definitive host is the feline species where sexual replication occurs resulting in the development of the highly infectious and environmentally resistant oocyst. Infection occurs via ingestion of tissue cysts from contaminated meat or oocysts from soil or water. Infection is typically asymptomatic in healthy individuals, but results in a life-long latent infection that can reactivate causing toxoplasmic encephalitis and death if the individual becomes immunocompromised. Meat contaminated with T. gondii cysts have been the primary source of infection in Europe and the United States, but recent changes in animal management and husbandry practices and improved food handling and processing procedures have significantly reduced the prevalence of T. gondii cysts in meat1, 2. Nonetheless, seroprevalence in humans remains relatively high suggesting that exposure from oocyst contaminated soil or water is likely. Indeed, waterborne outbreaks of toxoplasmosis have been reported worldwide supporting the theory exposure to the environmental oocyst form poses a significant health risk3-5. To date, research on understanding the prevalence of T. gondii oocysts in the water and environment are limited due to the lack of tools to detect oocysts in the environment 5, 6. This is primarily due to the lack of efficient purification protocols for obtaining large numbers of highly purified T gondii oocysts from infected cats for research purposes. This study describes the development of a modified CsCl method that easily purifies T. gondii oocysts from feces of infected cats that are suitable for molecular biological and tissue culture manipulation7.

Obtaining Highly Purified Toxoplasma gondii Oocysts by a Discontinuous Cesium Chloride Gradient

This study describes the development of a modified CsCl method that easily purifies T. gondii oocysts from feces of infected cats that are suitable for molecular biological and tissue culture manipulation

الحصول على عالي النقاء المقوسة الغوندية البيضات من قبل التدرج كلوريد السيزيوم متقطع

Toxoplasma gondii is an obligate intracellular protozoan pathogen that commonly infects humans. It is a well characterized apicomplexan associated with ...

Toxoplasma gondii Cyst Wall Formation in Activated Bone Marrow-derived Macrophages and Bradyzoite Conditions

Toxoplasma gondii is an obligate intracellular parasite that can invade any nucleated cell of warm-blooded animals. During infection, T. gondii disseminates as a fast replicating form called the tachyzoite. Tachyzoites convert into a slow-growing encysted form called the bradyzoite by a signaling process that is not well characterized. Within animals, bradyzoite cysts are found in the central nervous system and muscle tissue and represent the chronic stage of infection. Conversion to bradyzoites can be simulated in tissue culture by CO2 starvation, using medium with high a pH, or the addition of interferon gamma (IFN&gamma;). Bradyzoites are characterized by the presence of a cyst wall, to which the lectin Dolichos biflorus agglutinin (DBA) binds. Fluorescently labeled DBA is used to visualize the cyst wall in parasites grown in human foreskin fibroblasts (HFFs) that have been exposed to low CO2 and high pH medium. Similarly, parasites residing in murine bone marrow-derived macrophages (BMMs) display a cyst wall detectable by DBA after the BMMs are activated with IFN&gamma; and lipopolysaccharide (LPS). This protocol will demonstrate how to induce conversion of T. gondii to bradyzoites using a high pH growth medium with low CO2 and activation of BMMs. Host cells will be cultured on coverslips, infected with tachyzoites and either activated with addition of IFN&gamma; and LPS (BMMs) or exposed to a high pH growth medium (HFFs) for three days. Upon completion of infections, host cells will be fixed, permeabilized, and blocked. Cyst walls will be visualized using rhodamine DBA with fluorescence microscopy.

Toxoplasma gondii Cyst Wall Formation in Activated Bone Marrow-derived Macrophages and Bradyzoite Conditions

Toxoplasma gondii converts to a cyst form in response to environmental stresses, which can be mimicked in tissue culture models. This video demonstrates techniques to examine cyst wall formation by activating bone marrow-derived macrophages or changing growth medium pH in fibroblast cells.

التوكسوبلازما جدار الكيس الغوندية تشكيل المنشط تقوم البلاعم في نخاع العظام والمستمدة من الشروط المتباطئة

Toxoplasma gondii is an obligate intracellular parasite that can invade any nucleated cell of warm-blooded animals. During infection, T. gondii ...

A Genetic Screen to Isolate Toxoplasma gondii Host-cell Egress Mutants

The widespread, obligate intracellular, protozoan parasite Toxoplasma gondii causes opportunistic disease in immuno-compromised patients and causes birth defects upon congenital infection. The lytic replication cycle is characterized by three stages: 1. active invasion of a nucleated host cell; 2. replication inside the host cell; 3. active egress from the host cell. The mechanism of egress is increasingly being appreciated as a unique, highly regulated process, which is still poorly understood at the molecular level. The signaling pathways underlying egress have been characterized through the use of pharmacological agents acting on different aspects of the pathways1-5. As such, several independent triggers of egress have been identified which all converge on the release of intracellular Ca2+, a signal that is also critical for host cell invasion6-8. This insight informed a candidate gene approach which led to the identification of plant like calcium dependent protein kinase (CDPK) involved in egress9. In addition, several recent breakthroughs in understanding egress have been made using (chemical) genetic approaches10-12. To combine the wealth of pharmacological information with the increasing genetic accessibility of Toxoplasma we recently established a screen permitting the enrichment for parasite mutants with a defect in host cell egress13. Although chemical mutagenesis using N-ethyl-N-nitrosourea (ENU) or ethyl methanesulfonate (EMS) has been used for decades in the study of Toxoplasma biology11,14,15, only recently has genetic mapping of mutations underlying the phenotypes become routine16-18. Furthermore, by generating temperature-sensitive mutants, essential processes can be dissected and the underlying genes directly identified. These mutants behave as wild-type under the permissive temperature (35 &deg;C), but fail to proliferate at the restrictive temperature (40 &deg;C) as a result of the mutation in question. Here we illustrate a new phenotypic screening method to isolate mutants with a temperature-sensitive egress phenotype13. The challenge for egress screens is to separate egressed from non-egressed parasites, which is complicated by fast re-invasion and general stickiness of the parasites to host cells. A previously established egress screen was based on a cumbersome series of biotinylation steps to separate intracellular from extracellular parasites11. This method also did not generate conditional mutants resulting in weak phenotypes. The method described here overcomes the strong attachment of egressing parasites by including a glycan competitor, dextran sulfate (DS), that prevents parasites from sticking to the host cell19. Moreover, extracellular parasites are specifically killed off by pyrrolidine dithiocarbamate (PDTC), which leaves intracellular parasites unharmed20. Therefore, with a new phenotypic screen to specifically isolate parasite mutants with defects in induced egress, the power of genetics can now be fully deployed to unravel the molecular mechanisms underlying host cell egress.

A Genetic Screen to Isolate Toxoplasma gondii Host-cell Egress Mutants

Forward genetics is a powerful method to unravel the molecular level of how Toxoplasma egresses from its host cell. Protocols are provided to chemically mutagenize parasites, enrich for mutants with defects in induced egress, and validate the phenotype of cloned mutants.

شاشة الوراثية لعزل التوكسوبلازما جوندياي المسوخ الخروج المضيف الخلية

The widespread, obligate intracellular, protozoan parasite Toxoplasma gondii causes opportunistic disease in immuno-compromised patients and causes birth ...

Genetic Manipulation in &Delta;ku80 Strains for Functional Genomic Analysis of Toxoplasma gondii

Targeted genetic manipulation using homologous recombination is the method of choice for functional genomic analysis to obtain a detailed view of gene function and phenotype(s). The development of mutant strains with targeted gene deletions, targeted mutations, complemented gene function, and/or tagged genes provides powerful strategies to address gene function, particularly if these genetic manipulations can be efficiently targeted to the gene locus of interest using integration mediated by double cross over homologous recombination.
Due to very high rates of nonhomologous recombination, functional genomic analysis of Toxoplasma gondii has been previously limited by the absence of efficient methods for targeting gene deletions and gene replacements to specific genetic loci. Recently, we abolished the major pathway of nonhomologous recombination in type I and type II strains of T. gondii by deleting the gene encoding the KU80 protein1,2. The &Delta;ku80 strains behave normally during tachyzoite (acute) and bradyzoite (chronic) stages in vitro and in vivo and exhibit essentially a 100% frequency of homologous recombination. The &Delta;ku80 strains make functional genomic studies feasible on the single gene as well as on the genome scale1-4.
Here, we report methods for using type I and type II &Delta;ku80&Delta;hxgprt strains to advance gene targeting approaches in T. gondii. We outline efficient methods for generating gene deletions, gene replacements, and tagged genes by targeted insertion or deletion of the hypoxanthine-xanthine-guanine phosphoribosyltransferase (HXGPRT) selectable marker. The described gene targeting protocol can be used in a variety of ways in &Delta;ku80 strains to advance functional analysis of the parasite genome and to develop single strains that carry multiple targeted genetic manipulations. The application of this genetic method and subsequent phenotypic assays will reveal fundamental and unique aspects of the biology of T. gondii and related significant human pathogens that cause malaria (Plasmodium sp.) and cryptosporidiosis (Cryptosporidium).

Genetic Manipulation in &lt;em&gt;&amp;Delta;ku80&lt;/em&gt; Strains for Functional Genomic Analysis of &lt;em&gt;Toxoplasma gondii&lt;/em&gt;

Here we report a method for using type I and type II &Delta;ku80 strains of Toxoplasma gondii to efficiently generate targeted gene deletions and gene replacements for functional genomic analysis.

التلاعب الجيني في<em&gt; Δku80</em&gt; سلالات لتحليل الجينوم الوظيفي لل<em&gt; التوكسوبلازما جوندياي</em

Targeted genetic manipulation using homologous recombination is the method of choice for functional genomic analysis to obtain a detailed view of gene ...

Forward Genetics Screens Using Macrophages to Identify Toxoplasma gondii Genes Important for Resistance to IFN-&#947;-Dependent Cell Autonomous Immunity

Toxoplasma gondii, the causative agent of toxoplasmosis, is an obligate intracellular protozoan pathogen. The parasite invades and replicates within virtually any warm blooded vertebrate cell type. During parasite invasion of a host cell, the parasite creates a parasitophorous vacuole (PV) that originates from the host cell membrane independent of phagocytosis within which the parasite replicates. While IFN-dependent-innate and cell mediated immunity is important for eventual control of infection, innate immune cells, including neutrophils, monocytes and dendritic cells, can also serve as vehicles for systemic dissemination of the parasite early in infection. An approach is described that utilizes the host innate immune response, in this case macrophages, in a forward genetic screen to identify parasite mutants with a fitness defect in infected macrophages following activation but normal invasion and replication in na&#239;ve macrophages. Thus, the screen isolates parasite mutants that have a specific defect in their ability to resist the effects of macrophage activation. The paper describes two broad phenotypes of mutant parasites following activation of infected macrophages: parasite stasis versus parasite degradation, often in amorphous vacuoles. The parasite mutants are then analyzed to identify the responsible parasite genes specifically important for resistance to induced mediators of cell autonomous immunity. The paper presents a general approach for the forward genetics screen that, in theory, can be modified to target parasite genes important for resistance to specific antimicrobial mediators. It also describes an approach to evaluate the specific macrophage antimicrobial mediators to which the parasite mutant is susceptible. Activation of infected macrophages can also promote parasite differentiation from the tachyzoite to bradyzoite stage that maintains chronic infection. Therefore, methodology is presented to evaluate the importance of the identified parasite gene to establishment of chronic infection.

Forward Genetics Screens Using Macrophages to Identify Toxoplasma gondii Genes Important for Resistance to IFN-&amp;#947;-Dependent Cell Autonomous Immunity

Forward genetics is a powerful approach to identify genes in intracellular pathogens important for resistance to cell autonomous immunity. The current approach uses innate immune cells, specifically macrophages, to identify novel Toxoplasma gondii genes important for immune evasion.

الى الامام علم الوراثة شاشات طريق الضامة لتحديد<em&gt; التوكسوبلازما</em&gt; الجينات هامة الحصانة الذاتية للمقاومة إلى الإنترفيرون γ التي تعتمد على خلية

Toxoplasma gondii, the causative agent of toxoplasmosis, is an obligate intracellular protozoan pathogen. The parasite invades and replicates within ...

Retroviral Transduction of Bone Marrow Progenitor Cells to Generate T-cell Receptor Retrogenic Mice

T cell receptor (TCR) signaling is essential in the development and differentiation of T cells in the thymus and periphery, respectively. The vast array of TCRs proves studying a specific antigenic response difficult. Therefore, TCR transgenic mice were made to study positive and negative selection in the thymus as well as peripheral T cell activation, proliferation and tolerance. However, relatively few TCR transgenic mice have been generated specific to any given antigen. Thus, studies involving TCRs of varying affinities for the same antigenic peptide have been lacking. The generation of a new TCR transgenic line can take six or more months. Additionally, any specific backcrosses can take an additional six months. In order to allow faster generation and screening of multiple TCRs, a protocol for retroviral transduction of bone marrow was established with stoichiometric expression of the TCR&#945; and TCR&#946; chains and the generation of retrogenic mice. Each retrogenic mouse is essentially a founder, virtually negating a founder effect, while the length of time to generate a TCR retrogenic is cut from six months to approximately six weeks. Here we present a rapid and flexible alternative to TCR transgenic mice that can be expressed on any chosen background with any particular TCR.

We present a rapid and flexible protocol for a single T cell receptor (TCR) retroviral-based in vivo expression system. Retroviral vectors are used to transduce bone marrow progenitor cells to study T cell development and function of a single TCR in vivo as an alternative to TCR transgenic mice.

فيروسات تنبيغ من خلايا نخاع العظم السلف لتوليد خلايا T مستقبلات Retrogenic الفئران

T cell receptor (TCR) signaling is essential in the development and differentiation of T cells in the thymus and periphery, respectively.  The vast array ...

Development of Stem Cell-derived Antigen-specific Regulatory T Cells Against Autoimmunity

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic self-tolerance. Tregs represent about 5 - 10% of the mature CD4+ T cell subpopulation in mice and humans, with about 1 - 2% of those Tregs circulating in the peripheral blood. Induced pluripotent stem cells (iPSCs) can be differentiated into functional Tregs, which have a potential to be used for cell-based therapies of autoimmune diseases. Here, we present a method to develop antigen (Ag)-specific Tregs from iPSCs (i.e., iPSC-Tregs). The method is based on incorporating the transcription factor FoxP3 and an Ag-specific T cell receptor (TCR) into iPSCs and then differentiating on OP9 stromal cells expressing Notch ligands delta-like (DL) 1 and DL4. Following in vitro differentiation, the iPSC-Tregs express CD4, CD8, CD3, CD25, FoxP3, and Ag-specific TCR and are able to respond to Ag stimulation. This method has been successfully applied to cell-based therapy of autoimmune arthritis in a murine model. Adoptive transfer of these Ag-specific iPSC-Tregs into Ag-induced arthritis (AIA)-bearing mice has the ability to reduce joint inflammation and swelling and to prevent bone loss.

We present here a method to develop functional antigen (Ag)-specific regulatory T cells (Tregs) from induced pluripotent stem cells (iPSCs) for immunotherapy of autoimmune arthritis in a murine model.

تطوير المستمدة الخلية الجذعية خلايا T التنظيمية مستضد محددة ضد المناعة الذاتية

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic ...

Identification of Mediators of T-cell Receptor Signaling via the Screening of Chemical Inhibitor Libraries

The T-cell receptor (TCR) signaling pathway comprises a multitude of mediators that transmit signals upon the activation of the TCR. Different strategies have been proposed and implemented for the identification of new mediators of TCR signaling, which would improve the understanding of T-cell processes, including activation and thymic selection. We describe a screening assay that enables the identification of molecules that influence TCR signaling based on the activation of developing thymocytes. Strong TCR signals cause developing thymocytes to activate apoptotic machinery in a process known as negative selection. Through the application of kinase inhibitors, those with targets that affect TCR signaling are able to override the process of negative selection. The method detailed in this paper can be used to identify inhibitors of canonical kinases with established roles in the TCR signaling pathways and also inhibitors of new kinases yet to be established in the TCR signaling pathways. The screening strategy here can be applied to screens of higher throughput for the identification of novel druggable targets in TCR signaling.

Identification of Mediators of T-cell Receptor Signaling via the Screening of Chemical Inhibitor Libraries

This paper uses a flow-cytometry-based assay to screen libraries of chemical inhibitors for the identification of inhibitors and their targets that influence T-cell receptor signaling. The methods described here can also be expanded for high-throughput screenings.

تحديد وسطاء من خلايا تي مستقبلات الإشارات عن طريق فحص مكتبات المانع الكيميائية

The T-cell receptor (TCR) signaling pathway comprises a multitude of mediators that transmit signals upon the activation of the TCR. Different strategies ...

Single-cell Screening Method for the Selection and Recovery of Antibodies with Desired Specificities from Enriched Human Memory B Cell Populations

The human antibody repertoire represents a largely untapped source of potential therapeutic antibodies and useful biomarkers. While current computational methods, such as next generation sequencing (NGS), yield enormous sets of data on the antibody repertoire at the sequence level, functional data is required to identify which sequences are relevant for a particular antigen or set of antigens. Here, we describe a method to identify and recover individual antigen-specific antibodies from peripheral blood mononuclear cells (PBMCs) from a human blood donor. This method utilizes an initial enrichment of mature B cells and requires a combination of phenotypic cell markers and fluorescently-labeled protein to isolate IgG memory B cells via flow cytometry. The heavy and light chain variable regions are then cloned and re-screened. Although limited to the memory B cell compartment, this method takes advantage of flow cytometry to interrogate millions of B cells and returns paired heavy and light chain sequences from a single cell in a format ready for expression and confirmation of specificity. Antibodies recovered with this method can be considered for therapeutic potential, but can also link specificity and function with bioinformatic approaches to assess the B cell repertoire within individuals.

The BSelex method to identify and recover individual antigen-specific antibodies from human peripheral blood mononuclear cells combines flow cytometry with single cell PCR and cloning.

طريقة فحص خلية واحدة لاختيار واستعادة الأجسام المضادة مع الخصائص المطلوبة من الذاكرة البشرية المخصب B مجموعات الخلايا

The human antibody repertoire represents a largely untapped source of potential therapeutic antibodies and useful biomarkers. While current computational ...

Stem Cell-Derived Viral Ag-Specific T Lymphocytes Suppress HBV Replication in Mice

Hepatitis B virus (HBV) infection is a global health issue. With over 350 million people affected worldwide, HBV infection remains the leading cause of liver cancer. This is a major concern, especially in developing countries. Failure of the immune system to mount an effective response against HBV leads to chronic infection. Although HBV vaccine is present and novel antiviral medicines are being created, eradication of virus-reservoir cells remains a major health topic. Described here is a method for the generation of viral antigen (Ag) -specific CD8+ cytotoxic T lymphocytes (CTLs) derived from induced pluripotent stem cells (iPSCs) (i.e., iPSC-CTLs), which have the ability to suppress HBV replication. HBV replication is efficiently induced in mice through hydrodynamic injection of an HBV expression plasmid, pAAV/HBV1.2, into the liver. Then, HBV surface Ag-specific mouse iPSC-CTLs are adoptively transferred, which greatly suppresses HBV replication in the liver and blood as well as prevents HBV surface Ag expression in hepatocytes. This method demonstrates HBV replication in mice after hydrodynamic injection and that stem cell-derived viral Ag-specific CTLs can suppress HBV replication. This protocol provides a useful method for HBV immunotherapy.

Presented here is a protocol for the effective suppression of hepatitis B virus (HBV) replication in mice by utilizing adoptive cell transfer (ACT) of stem cell-derived viral antigen (Ag)-specific T lymphocytes. This procedure may be adapted for potential ACT-based immunotherapy of HBV infection.

الخلايا الجذعية المشتقة الفيروسية Ag محددة T الخلايا الليمفاوية قمع النسخ المتماثل HBV في الفئران

Hepatitis B virus (HBV) infection is a global health issue. With over 350 million people affected worldwide, HBV infection remains the leading cause of ...