Name: isolation and transplantation of different aged murine thymic grafts.
Uploaded: 2015-05-13T14:00:00.000+00:00
Duration: 5 min 47 s
Description: Watch this Scientific Journal Video about Isolation and Transplantation of Different Aged Murine Thymic Grafts. at JoVE.com

This work was supported by funding received from the National Institutes of Health (1R01AI083269).

Os estudos de murino foram aprovados pelo cuidado e uso Comitê Institucional Animal (IACUC) da Universidade de North Carolina em Chapel Hill e todos os cuidados com os animais estava em conformidade com as orientações IACUC. 1. Preparação do recém-nascido e Adulto Thymi <ol><li> Prepare todos os reagentes e equipamentos antes da eutanásia de ratos doadores. </li><li> Esterilizar instrumentos cirúrgicos por autoclavagem ou outros métodos apropriados. Todos os procedimentos cirúrgicos devem ser realizados sob uma câmara de fluxo laminar, para manter as condições estéreis e evitar a contaminação. Monte as ferramentas necessárias para a extração de thymi de camundongos doadores. </li><li> Encha um prato de 60 milímetros com estéril 1x PBS (pH 7,4) e colocar no gelo no interior do exaustor. Isto será usado para armazenar brevemente timos excisado a partir de ratinhos dadores antes do transplante. </li><li> De acordo com as orientações éticas, sacrificar os ratinhos dadores recém-nascidos e adultos por decapitação ratos doadores por asfixia com CO2, seguido por deslocação cervical. </li><li> Para removal do timo: Coloque o mouse em uma posição de decúbito dorsal sobre uma toalha de papel absorvente estéril e spray com etanol 70% antes de fazer uma incisão. </li><li> Expor a cavidade torácica e abdominal, fazendo uma incisão na linha média através da pele. Dobrar a pele sobre o peito e os membros anteriores para revelar a cavidade torácica. </li><li> Faça duas incisões laterais através do diafragma e da caixa torácica para expor o mediastino superior e anterior cavidade torácica. O timo deve ser visível como dois lóbulos branco imediatamente acima e adjacente ao coração. </li><li> Desmembrar o tecido conjuntivo em torno do timo com uma pinça fina, tornando certas para não perturbar a cápsula. Embora retendo o tórax com uma pinça, utilizar um segundo par de fórceps para extrair os dois lóbulos do timo posicionando pinças curvas por baixo do órgão e puxando verticalmente. Isto pode ser feito usando um escopo de dissecação para a extracção de timos de ratos recém-nascidos. </li><li> Inserir o timo no 60 milímetros dish estéril contendo 1x PBS (pH 7,4) em gelo e lóbulos tímicos separadas por corte através do istmo conjuntivo. Remover todos os detritos dos lobos do timo tornando certas para não danificar a cápsula, e cortar o timo para o número adequado de secções para transplante. </li><li> Não manipular o thymi obtidos a partir de ratos recém-nascidos. NOTA: Usado para um máximo de dois ratinhos receptores (1 lobo por beneficiário). </li><li> Transplantar a thymi obtidos a partir de ratos adultos, até um máximo de 4-6 ratinhos receptores. Utilizando um par de pinças, cuidadosamente compreender um adulto lóbulo do timo, como mostrado na Figura 1, o corte timo em três partes iguais, usando tesouras cirúrgicas. </li><li> Repita os passos de 1,3-1,4 para cada camundongo doador. A fim de limitar o tempo timos estão expostos, preparar um doador de timo de cada vez. </li></ol> 2. Thymus implantação sob a cápsula renal <ol><li> Montagem do equipamento de pré-esterilizado listados na Tabela 1. Assépticastécnica deve ser utilizada durante o decurso do processo, para prevenir a exposição a receptores de transplantes-ferramentas ou reagentes contaminados. </li><li> Antes do transplante, pesar e etiquetar cada rato destinatário. </li><li> Configure o microscópio de dissecação e circuito de anestesia na capela de fluxo laminar. </li><li> Usando um barbeador elétrico, raspar o lado esquerdo do mouse destinatário e garantir que não haja cabelo permanece ao redor da área usada para fazer a incisão. </li><li> Ligue vaporizador isofluorano e anestesiar o rato usando uma dose de entre 1-2%. Verificar anesthetization adequada antes de iniciar o procedimento cirúrgico através da verificação de uma ausência de reflexo seguinte toe pitada. </li><li> Após o mouse está devidamente anestesiados, aplique pomada veterinária aos olhos do mouse para prevenir o ressecamento e preparar o mouse para o transplante da seguinte forma: </li><li> Posicione o mouse sob o microscópio de dissecação em posição de decúbito lateral direito, de modo que o lado raspada está voltado para cima. Starting no centro da área cirúrgica, dispensar em um movimento circular usando uma pipeta de transferência descartável etanol a 70%, seguido de povidona-iodo (Betadine). Repita o tratamento de etanol / betadine 3 vezes antes de fazer uma incisão. </li><li> Usando uma tesoura de dissecção fazer uma incisão flanco 1-2 cm diretamente acima do rim. </li><li> Usando fórceps médias agarrar tecido conjuntivo adjacente ao rim e suavemente levantar o rim de modo a que ela se encontra no topo da musculatura. Para manter o rim exposta e no lugar sobre a musculatura, insira um braço de fórceps médio debaixo do rim, com especial atenção para não perturbar o ílio renal. </li><li> A fim de evitar a dessecação do tecido, irrigar o rim com estéril 1x PBS (pH 7,4) durante cada passo até que a manipulação do rim e rim cápsula é completa. </li><li> Usando fórceps finos apertar e levantar a cápsula perto da borda do rim mais distai para as glândulas supra-renais para separá-lo do rim. </li><li> Utilize um calibre 18agulha para fazer uma incisão grande o suficiente para inserir a peça preparada de timo do doador (Figura 2A). Certifique-se de manter a incisão capsular tão pequeno quanto possível para impedir a deslocação do enxerto ao longo do tempo. </li><li> Mantendo a cápsula puxada para fora do rim, utilizar um segundo par de uma pinça fina para inserir o enxerto por baixo da cápsula e empurrar o timo o mais à frente a partir da incisão capsular quanto possível (Figura 2B). </li><li> Remover a pinça de debaixo do rim, e retornar suavemente o rim de volta no lugar através da incisão. </li><li> Fechar a musculatura suturando a parede peritoneal e aplicando betadine uma vez fechada. Após a sutura está completa, aplicar agrafos para fechar a derme e aplicar betadine para a área circundante. </li><li> Devolver o mouse para uma gaiola que foi aquecido usando uma lâmpada de calor. </li><li> Monitorar cada rato pós-operatório até que recupere a consciência plena e mobilidade e não coloque ratos that não se recuperaram após anestesia em uma gaiola com outros animais. </li><li> Tratar ratos com pós-operatório drogas de gerenciamento de dor, conforme necessário. Fornecer ratinhos com analgésicos pós-operatórias tais como acetaminofeno na água de beber numa concentração de 1,6 mg / ml. </li><li> Repita os passos de 2,3-2,9 para cada rato destinatário. </li><li> Certifique-se de que o retorno ratos para atividades normais dentro de 1 hora de pós-operatório. Monitorar o peso pós-operatório, as habilidades motoras, assim como a actividade de beber e a alimentação de cada murganho para determinar as complicações que surgem como um resultado do procedimento de transplante. NOTA: perda de peso no pós-operatório, quando comparado ao peso pré-operatório, bem como a mobilidade alterada ou falha para comer ou beber pode indicar complicações. </li><li> Monitorar a reconstituição de células T no sangue periférico por sangramento através de ratinhos cauda entalhe seguido de separação de linfócitos, utilizando Lympholyte meios de separação de células de acordo com as especificações do fabricante. Realizar T caracteriz celularção através de coloração de linfócitos com anticorpos conjugados fluorescentes específicos para os marcadores de células T CD3, CD4, e CD8, bem como um discriminador morto vivo, tais como um éster de succinimidilo activado por fluorescência 8. Análise conforme mostrado na Figura 3 pode ser conseguido por meio de propagação em singuletos, células vivas e células CD3 positivas. </li></ol>

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	<li>Kappler, J. W., Roehm, N., Marrack, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=T+cell+tolerance+by+clonal+elimination+in+the+thymus.">T cell tolerance by clonal elimination in the thymus.</a> Cell. 49 (2), 273-280 (1987).</li><li>Takahama, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Journey+through+the+thymus:+stromal+guides+for+T-cell+development+and+selection.">Journey through the thymus: stromal guides for T-cell development and selection.</a> Nat. Rev. Immunol. 6, 127-135 (2006).</li><li>Klein, L., Kyewski, B., Allen, P. M., Hogquist, K. 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Immunol. 2 (11), 1025-1031 (2001).</li><li>Anderson, G., Jenkinson, E. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigating+central+tolerance+with+reaggregate+thymus+organ+cultures.">Investigating central tolerance with reaggregate thymus organ cultures.</a> Methods. Mol. Biol. 380, 185-196 (2007).</li><li>He, Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thymic+development+of+autoreactive+T+cells+in+NOD+mice+is+regulated+in+an+age-dependent+manner.">Thymic development of autoreactive T cells in NOD mice is regulated in an age-dependent manner.</a> J. Immunol. 191 (12), 5858-5866 (2013).</li><li>Stewart, C. C., Stewart, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chapter+6.+Immunophenotyping.">Chapter 6. Immunophenotyping.</a> Current Protocols in Cytometry. , (2001).</li><li>Rice, H. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thymic+transplantation+for+complete+DiGeorge+syndrome:+medical+and+surgical+considerations.">Thymic transplantation for complete DiGeorge syndrome: medical and surgical considerations.</a> J. Pediatr. Surg. 39 (11), 1607-1615 (2004).</li><li>Markert, M. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transplantation+of+thymus+tissue+in+complete+DiGeorge+Syndrome.">Transplantation of thymus tissue in complete DiGeorge Syndrome.</a> N. Engl. J. 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S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+FOXN1-Deficiency+is+associated+with+ab+double-negative+and+FoxP3++T-cell+expansions+that+are+distinctly+modulated+upon+thymic+transplantation.">Human FOXN1-Deficiency is associated with ab double-negative and FoxP3+ T-cell expansions that are distinctly modulated upon thymic transplantation.</a> PLoS One. 7 (5), e37042 (2012).</li><li>Chinn, I. K., Milner, J. D., Scheinberg, P., Douek, D. C., Markert, M. 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The authors do not have any competing financial interests to disclose.

Events regulating thymic selection are poorly understood. Recent studies have demonstrated ontogenic changes in the efficiency of selection. Coupling this approach with different transgenic thymus donor and recipient mice will further facilitate studies to identify the events and parameters that regulate thymic selection. Notably, thymic transplantation is used for the treatment and management of T cell and thymic disorders seen for instance in athymic infants lacking functional T cells and in patients with DiGeorge synd...

O timo é um órgão em que os eventos críticos no desenvolvimento de células T ocorrem 1. Timócitos residente, mediante rearranjo do receptor de células T (TCR) e dos genes α β, passam por uma série de interacções com lymphostromal e células apresentadoras de antigénio (APC) nas regiões corticais e medulares do timo 2. Selecção positiva tímico é mediada por células epiteliais tímicas corticais (TEC) para produzir timócitos que reconhecem péptidos antigénicos no contexto do complexo de histocompatibilidade principal hospedeiro (MHC) de classe I e moléculas II 2-3. Subsequente selecção tímica negativa envolve purga de timócitos auto-reactivas, impulsionado por uma interacção com a TEC medular ou células dendríticas (DC) que apresentam péptidos derivados de auto-proteínas ligadas por MHC de classe I e moléculas 3 II. O resultado final destes processos é o estabelecimento de uma pool de células maduras CD4 + e CD8 + T capazes de responder a um espectro amplode antigénios estranhos enquanto exibem reactividade mínima para auto-proteínas 4. A eficiência de eventos de selecção do timo é influenciada por uma série de factores, incluindo maturação do timo, a frequência de medular e cortical do TCE, composição subconjunto de DC timo, e a fonte de precursores do timo 3. Notavelmente, a seleção do timo aberrante pode resultar em auto-imunes 5 ou imunodeficientes patologias, que surgem a partir de selecção negativa ou positiva prejudicada, respectivamente. Os eventos moleculares que regulam a selecção tímica, no entanto, são pouco compreendidos. Em abordagens in vitro, tais como culturas de órgãos tímicos reaggregate (RTOC) 6, têm provado ser úteis para analisar os acontecimentos básicos associados com a selecção tímica, mas não totalmente recapitular a dinâmica do curso em eventos in vivo. Como resultado, esta abordagem baseada em transplante de timo foi criada para melhores eventos estudo de seleção de timócitos in vivo 7 </sup&gt;. Este protocolo descreve o transplante thymi de camundongos recém-nascidos e adultos doadores em ratinhos receptores SCID imunodeficientes. Esta técnica permite o estudo de mecanismos que regulam a selecção tímica positiva e negativa, bem como a saída do timo de vários subconjuntos de células T durante a ontogenia. Mais recentemente, esta abordagem tem sido utilizado para demonstrar que a eficácia de selecção tímica é limitado logo depois do nascimento em ratinhos conduz a um aumento do desenvolvimento de células T auto-reactivas, e um reduzido repertório de células T específicas para antigenes estranhos 7.

<table><tbody><tr><td>Ethanol&amp;nbsp;</td><td>Decon Laboratories</td><td>2705HC</td><td></td></tr><tr><td>PBS</td><td>GIBCO</td><td>14190-144</td><td>pH 7.4</td></tr><tr><td>Betadine Solution</td><td>Purdue Products</td><td>67618-150-17</td><td></td></tr><tr><td>18 gauge needle</td><td>BD</td><td>305195</td><td></td></tr><tr><td>Sutures (1.0 metric)</td><td>Ethicon</td><td>J493G</td><td>18&quot; (45cm)</td></tr><tr><td>AUTOCLIP Wound Clips (9mm)</td><td>Clay Adams&amp;reg; Brand</td><td>427631</td><td></td></tr><tr><td>Transfer pipette</td><td>Fisher Scientific</td><td>13-711-20</td><td>Sterile, disposable</td></tr><tr><td>Mouse anti-CD3 Ab</td><td>eBioscience</td><td>11-0031-85</td><td>Clone: 1452C11</td></tr><tr><td>Mouse anti-CD4 Ab</td><td>eBioscience</td><td>48-0042-82</td><td>Clone: RM4-5</td></tr><tr><td>Mouse anti-CD8 Ab</td><td>eBioscience</td><td>25-0081-82</td><td>Clone: 53-6.7</td></tr><tr><td>Lancet</td><td>Medipoint</td><td>Goldenrod 4mm</td><td></td></tr><tr><td>Pacific Orange Succinimidyl Ester, Triethylammonium Salt</td><td>Invitrogen</td><td>P30253</td><td></td></tr><tr><td>96-well round botton polypropylene plates</td><td>Corning</td><td>3365</td><td></td></tr><tr><td>1.2 ml polypropylene cluster tubes</td><td>Corning</td><td>4401</td><td></td></tr><tr><td>5 ml polypropylene round-bottom tubes</td><td>BD</td><td>352002</td><td></td></tr><tr><td>40uM Nylon Cell Strainer</td><td>Falcon</td><td>352340</td><td></td></tr><tr><td>16% Paraformaldehyde Solution, EM Grade</td><td>Electron Microscopy Services</td><td>15710</td><td>Hazardous</td></tr><tr><td>Puralube Optical Ointment</td><td>Fisher Scientific</td><td>NC0138063</td><td></td></tr><tr><td>Lympholyte</td><td>Cedarlane</td><td>CL5030</td><td></td></tr><tr><td>60 mm cell culture dish</td><td>Corning</td><td>430196</td><td>60 mm x 15 mm, Sterile</td></tr></tbody></table>

isolation and transplantation of different aged murine thymic grafts.

Os mecanismos que regulam a eficácia da selecção do timo permanecem mal definidos. O método aqui apresentado permite em análises in vivo do desenvolvimento e selecção das células T específicas para auto-antigénios e estrangeiras. A abordagem implica o implante de enxertos de timo derivados de várias ratos envelhecidos em recipientes SCID imunodeficientes. Ao longo de um período relativamente curto de tempo, os destinatários são completamente reconstituído com células T derivadas do enxerto de timo implantado. Apenas timócitos semeando o timo no momento de isolamento submetidos a selecção e se desenvolvem em células T maduras. Como tal, as alterações na natureza e especificidade das células T enxertadas como uma função do timo de eventos dependentes da idade, pode ser avaliada. Embora perícia técnica é necessária para o transplante bem sucedido do timo, este método proporciona uma estratégia única para o estudo in vivo, uma vasta gama de patologias que são devido a um resultado ou de função e / ou aberrante do timo homeostasé.

O sucesso deste procedimento é dependente de trauma cirúrgico mínima, bem como o posicionamento preciso do enxerto por baixo da cápsula do rim. O enxerto de timo deve ser cortado para assegurar tamanho adequado secções do timo para transplante subsequente, como mostrado na Figura 1. Seguindo o esquema na Figura 1, timos de ratos recém-nascidos ou adultos podem ser utilizadas para transplante subcapsular com sucesso o enxerto de células T resultados consistentes e reproduzíveis....

Watch this Scientific Journal Video about Isolation and Transplantation of Different Aged Murine Thymic Grafts. at JoVE.com

Isolation and Transplantation of Different Aged Murine Thymic Grafts.

This report provides a detailed description of transplanting murine thymi from different aged donor mice under the kidney capsule of immunodeficient mouse recipients. The goal of this approach is to model T cell development and thymic selection events in vivo.

Isolamento e Transplante de diferentes envelhecidas murino tímicos enxertos.

The mechanisms that regulate the efficacy of thymic selection remain ill-defined. The method presented here allows in vivo analyses of the development and ...

isolation-and-transplantation-of-different-aged-murine-thymic-grafts

Research

JoVE Journal

Immunology and Infection

13.7K visualizações.  University of North Carolina at Chapel Hill. This report provides a detailed description of transplanting murine thymi from different aged donor mice under the kidney capsule of immunodeficient mouse recipients. The goal of this approach is to model T cell development and thymic selection events in vivo. 

Vídeo: Isolation and Transplantation of Different Aged Murine Thymic Grafts.

Characterization of Thymic Settling Progenitors in the Mouse Embryo Using In Vivo and In Vitro Assays

Characterizing thymic settling progenitors is important to understand the pre-thymic stages of T cell development, essential to devise strategies for T cell replacement in lymphopenic patients. We studied thymic settling progenitors from murine embryonic day 13 and 18 thymi by two complementary in vitro and in vivo techniques, both based on the &#8220;hanging drop&#8221; method. This method allowed colonizing irradiated fetal thymic lobes with E13 and/or E18 thymic progenitors distinguished by CD45 allotypic markers and thus following their progeny. Colonization with mixed populations allows analyzing cell autonomous differences in biologic properties of the progenitors while colonization with either population removes possible competitive selective pressures. The colonized thymic lobes can also be grafted in immunodeficient male recipient mice allowing the analysis of the mature T cell progeny in vivo, such as population dynamics of the peripheral immune system and colonization of different tissues and organs. Fetal thymic organ cultures revealed that E13 progenitors developed rapidly into all mature CD3+ cells and gave rise to the canonical &#947;&#948; T cell subset, known as dendritic epithelial T cells. In comparison, E18 progenitors have a delayed differentiation and were unable to generate dendritic epithelial T cells. The monitoring of peripheral blood of thymus-grafted CD3-/- mice further showed that E18 thymic settling progenitors generate, with time, larger numbers of mature T cells than their E13 counterparts, a feature that could not be appreciated in the short term fetal thymic organ cultures.

Characterization of Thymic Settling Progenitors in the Mouse Embryo Using In Vivo and In Vitro Assays

This article describes in vivo and in vitro methodology to characterize the thymic settling progenitors by the analysis of the kinetics of generation, phenotype and numbers of their T cell progeny.

Caracterização de Thymic Settling Progenitores no embrião do rato Usando<em&gt; In Vivo</em&gt; E<em&gt; In Vitro</em&gt; Os ensaios

Characterizing thymic settling progenitors is important to understand the pre-thymic stages of T cell development, essential to devise strategies for T ...

Biologia do Desenvolvimento

Intravital Imaging of the Mouse Thymus using 2-Photon Microscopy

Two-photon Microscopy (TPM) provides image acquisition in deep areas inside tissues and organs. In combination with the development of new stereotactic tools and surgical procedures, TPM becomes a powerful technique to identify "niches" inside organs and to document cellular "behaviors" in live animals. While intravital imaging provides information that best resembles the real cellular behavior inside the organ, it is both more laborious and technically demanding in terms of required equipment/procedures than alternative ex vivo imaging acquisition. Thus, we describe a surgical procedure and novel "stereotactic" organ holder that allows us to follow the movements of Foxp3+ cells within the thymus.
Foxp3 is the master regulator for the generation of regulatory T cells (Tregs). Moreover, these cells can be classified according to their origin: ie. thymus-differentiated Tregs are called "naturally-occurring Tregs" (nTregs), as opposed to peripherally-converted Tregs (pTregs). Although significant amount of research has been reported in the literature concerning the phenotype and physiology of these T cells, very little is known about their in vivo interactions with other cells. This deficiency may be due to the absence of techniques that would permit such observations. The protocol described in this paper provides a remedy for this situation.
Our protocol consists of using nude mice that lack an endogenous thymus since they have a punctual mutation in the DNA sequence that compromises the differentiation of some epithelial cells, including thymic epithelial cells. Nude mice were gamma-irradiated and reconstituted with bone marrows (BM) from Foxp3-KIgfp/gfp mice. After BM recovery (6 weeks), each animal received embryonic thymus transplantation inside the kidney capsule. After thymus acceptance (6 weeks), the animals were anesthetized; the kidney containing the transplanted thymus was exposed, fixed in our organ holder, and kept under physiological conditions for in vivo imaging by TPM. We have been using this approach to study the influence of drugs in the generation of regulatory T cells.

We have developed novel laboratory tools and protocols for intravital imaging acquisition of the thymus. Our technique should help in the identification of &#x201C;niches&#x201D; within the thymus where T cell development occurs.

Imagem intravital da Thymus rato usando 2-Photon Microscopia

Two-photon Microscopy (TPM) provides image acquisition in deep areas inside tissues and organs. In combination with the development of new stereotactic ...

Imunologia e Infecção

Induction of Graft-versus-host Disease and In Vivo T Cell Monitoring Using an MHC-matched Murine Model

Graft-versus-host disease (GVHD) is the limiting barrier to the broad use of bone marrow transplant as a curative therapy for a variety of hematological deficiencies. GVHD is caused by mature alloreactive T cells present in the bone marrow graft that are infused into the recipient and cause damage to host organs. However, in mice, T cells must be added to the bone marrow inoculum to cause GVHD. Although extensive work has been done to characterize T cell responses post transplant, bioluminescent imaging technology is a non-invasive method to monitor T cell trafficking patterns in vivo. 
Following lethal irradiation, recipient mice are transplanted with bone marrow cells and splenocytes from donor mice. T cell subsets from L2G85.B6 (transgenic mice that constitutively express luciferase) are included in the transplant. By only transplanting certain T cell subsets, one is able to track specific T cell subsets in vivo, and based on their location, develop hypotheses regarding the role of specific T cell subsets in promoting GVHD at various time points. At predetermined intervals post transplant, recipient mice are imaged using a Xenogen IVIS CCD camera. Light intensity can be quantified using Living Image software to generate a pseudo-color image based on photon intensity (red = high intensity, violet = low intensity). 
Between 4-7 days post transplant, recipient mice begin to show clinical signs of GVHD. Cooke et al.1 developed a scoring system to quantitate disease progression based on the recipient mice fur texture, skin integrity, activity, weight loss, and posture. Mice are scored daily, and euthanized when they become moribund. Recipient mice generally become moribund 20-30 days post transplant. 
Murine models are valuable tools for studying the immunology of GVHD. Selectively transplanting particular T cell subsets allows for careful identification of the roles each subset plays. Non-invasively tracking T cell responses in vivo adds another layer of value to murine GVHD models.

Induction of Graft-versus-host Disease and In Vivo T Cell Monitoring Using an MHC-matched Murine Model

Murine bone marrow transplantation is a widely used technique to study immunological mechanisms governing graft-versus-host disease in humans. The ability to monitor T cell trafficking patterns in vivo allows for detailed analysis of the development and perpetuation of T cell responses during graft-versus-host disease.

Indução de enxerto-versus-hospedeiro de Doenças e<em&gt; Em Vivo</em&gt; Monitoramento celular T Usando um modelo murino de MHC de correspondência

Graft-versus-host disease (GVHD) is the limiting barrier to the broad use of bone marrow transplant as a curative therapy for a variety of hematological ...

Transplantation of Tail Skin to Study Allogeneic CD4 T Cell Responses in Mice

The study of T cell responses and their consequences during allo-antigen recognition requires a model that enables one to distinguish between donor and host T cells, to easily monitor the graft, and to adapt the system in order to answer different immunological questions. Medawar and colleagues established allogeneic tail-skin transplantation in mice in 1955. Since then, the skin transplantation model has been continuously modified and adapted to answer specific questions. The use of tail-skin renders this model easy to score for graft rejection, requires neither extensive preparation nor deep anesthesia, is applicable to animals of all genetic background, discourages ischemic necrosis, and permits chemical and biological intervention. 
In general, both CD4+ and CD8+ allogeneic T cells are responsible for the rejection of allografts since they recognize mismatched major histocompatibility antigens from different mouse strains. Several models have been described for activating allogeneic T cells in skin-transplanted mice. The identification of major histocompatibility complex (MHC) class I and II molecules in different mouse strains including C57BL/6 mice was an important step toward understanding and studying T cell-mediated alloresponses. In the tail-skin transplantation model described here, a three-point mutation (I-Abm12) in the antigen-presenting groove of the MHC-class II (I-Ab) molecule is sufficient to induce strong allogeneic CD4+ T cell activation in C57BL/6 mice. Skin grafts from I-Abm12 mice on C57BL/6 mice are rejected within 12-15 days, while syngeneic grafts are accepted for up to 100 days. The absence of T cells (CD3-/- and Rag2-/- mice) allows skin graft acceptance up to 100 days, which can be overcome by transferring 2 x 104 wild type or transgenic T cells. Adoptively transferred T cells proliferate and produce IFN-&#947; in I-Abm12-transplanted Rag2-/- mice.

Tail-skin transplantation is a powerful model for studying T cell-dependent rejection and tolerance induction during allogeneic immune responses in mice. The advantages of this protocol are minor invasive surgery, and ease of monitoring with no need to sacrifice the recipient mouse.

O transplante de pele da cauda para estudar as respostas das células T CD4 alogênico em camundongos

The study of T cell responses and their consequences during allo-antigen recognition requires a model that enables one to distinguish between donor and ...

Isolation, Identification, and Purification of Murine Thymic Epithelial Cells

The thymus is a vital organ for T lymphocyte development. Of thymic stromal cells, thymic epithelial cells (TECs) are particularly crucial at multiple stages of T cell development: T cell commitment, positive selection and negative selection. However, the function of TECs in the thymus remains incompletely understood. In the article, we provide a method to isolate TEC subsets from fresh mouse thymus using a combination of mechanical disruption and enzymatic digestion. The method allows thymic stromal cells and thymocytes to be efficiently released from cell-cell and cell-extracellular matrix connections and to form a single-cell suspension. Using the isolated cells, multiparameter flow cytometry can be applied to identification and characterization of TECs and dendritic cells. Because TECs are a rare cell population in the thymus, we also describe an effective way to enrich and purify TECs by depleting thymocytes, the most abundant cell type in the thymus. Following the enrichment, cell sorting time can be decreased so that loss of cell viability can be minimized during purification of TECs. Purified cells are suitable for various downstream analyses like Real Time-PCR, Western blot and gene expression profiling. The protocol will promote research of TEC function and as well as the development of in vitro T cell reconstitution.

Here we describe an efficient method for isolation, identification, and purification of mouse thymic epithelial cells (TECs). The protocol can be utilized for studies of thymus function for normal T cell development, thymus dysfunction, and T cell reconstitution.

Isolamento, identificação e purificação de células epiteliais do timo murino

The thymus is a vital organ for T lymphocyte development. Of thymic stromal cells, thymic epithelial cells (TECs) are particularly crucial at multiple ...

Murine Full-thickness Skin Transplantation

Murine full-thickness skin transplantation is a well-established in vivo model to study alloimmune response and graft rejection. Despite its limited application to humans, skin transplantation in mice has been widely employed for transplantation research. The procedure is easy to learn and perform, and it does not require delicate microsurgical techniques nor extensive training. Moreover, graft rejection in this model occurs in a very reproducible immunological reaction and is easily monitored by direct inspection and palpation. In addition, secondary skin transplantation with donor-matched or third-party skin grafts can be performed on more complex transplant models as an alternative and uncomplicated method to assess donor-specific tolerance. The complications are low and are in general limited to anesthesia overdose or respiratory distress after the procedure. Graft failure, on the other hand, occurs commonly as a result of poor preparation of the graft, incorrect positioning in the graft bed, or inappropriate placement of the bandage. In this article, we present a protocol for full-thickness skin transplantation in mice and describe the important steps necessary for a successful procedure.

Murine full-thickness skin transplantation is a well-established model to study rejection in an alloimmune setting. Here, we provide a tutorial of each step involved in performing a BALB/c--&#62;C57BL/6 full-thickness skin transplant.

Murino Transplante de pele de espessura total

Murine full-thickness skin transplantation is a well-established in vivo model to study alloimmune response and graft rejection. Despite its limited ...

A Novel Microsurgical Model for Heterotopic, En Bloc Chest Wall, Thymus, and Heart Transplantation in Mice

Exploration of novel strategies in organ transplantation to prolong allograft survival and minimizing the need for long-term maintenance immunosuppression must be pursued. Employing vascularized bone marrow transplantation and co-transplantation of the thymus have shown promise in this regard in various animal models.1-11 Vascularized bone marrow transplantation allows for the uninterrupted transfer of donor bone marrow cells within the preserved donor microenvironment, and the incorporation of thymus tissue with vascularized bone marrow transplantation has shown to increase T-cell chimerism ultimately playing a supportive role in the induction of immune regulation. The combination of solid organ and vascularized composite allotransplantation can uniquely combine these strategies in the form of a novel transplant model. Murine models serve as an excellent paradigm to explore the mechanisms of acute and chronic rejection, chimerism, and tolerance induction, thus providing the foundation to propagate superior allograft survival strategies for larger animal models and future clinical application. Herein, we developed a novel heterotopic en bloc chest wall, thymus, and heart transplant model in mice using a cervical non-suture cuff technique. The experience in syngeneic and allogeneic transplant settings is described for future broader immunological investigations via an instructional manuscript and video supplement.

To study combined solid organ and vascularized composite allotransplantation, we describe a novel heterotopic en bloc chest wall, thymus, and heart transplant model in mice using a cervical non-suture cuff technique.

A Microsurgical Modelo Novel para heterotópico, em bloco da parede torácica, Thymus, e Transplante Cardíaco em Ratos

Exploration of novel strategies in organ transplantation to prolong allograft survival and minimizing the need for long-term maintenance immunosuppression ...

Medicina

Renal Subcapsular Transplantation of 2'-Deoxyguanosine-Treated Murine Embryonic Thymus in Nude Mice

The thymus is an important central immune organ, which plays an essential role in the development and differentiation of T cells. Thymus transplantation is an important method for investigating thymic epithelial cell function and T cells maturation in vivo. Here we will describe the experimental methods used within our laboratory to transplant 2&#8217;-deoxyguanosine (to deplete donor&#8217;s lymphocytes) treated embryonic thymus into the renal capsule of an athymic nude mouse. This method is both simple and efficient and does not require special skills or devices. The results obtained via this simple method showed that transplanted thymus can effectively support the recipient&#8217;s T cells production. Additionally, several key points with regards to the protocol will be further elucidated.

We provide a simple and efficient method to transplant 2&#8217;-deoxyguanosine treated E18.5 thymus into the renal capsule of a nude mouse. This method should aide in the study of both thymic epithelial cells function and T cells maturation.

Transplantação subcapsular renal do Thymus Embryonic murine 2 '-Deoxyguanosine-Tratado em ratos nus

The thymus is an important central immune organ, which plays an essential role in the development and differentiation of T cells. Thymus transplantation ...

Otimizando o isolamento de células estromais do timo e da medula óssea

Stromal Cell Isolation From Hematopoietic Organs

Single-cell sequencing has enabled the mapping of heterogeneous cell populations in the stroma of hematopoietic organs. These methodologies provide a lens through which to study previously unresolved heterogeneity at steady state, as well as changes in cell type representation induced by extrinsic stresses or during aging. Here, we present step-wise protocols for the isolation of high-quality stromal cell populations from murine and human thymus, as well as murine bone and bone marrow. Cells isolated through these protocols are suitable for generating high-quality single-cell multiomics datasets. The impacts of sample digestion, hematopoietic lineage depletion, FACS analysis/sorting, and how these factors influence compatibility with single-cell sequencing are discussed here. With examples of FACS profiles indicating successful and inefficient dissociation and downstream stromal cell yields in post-sequencing analysis, recognizable pointers for users are provided. Considering the specific requirements of stromal cells is crucial for acquiring high-quality and reproducible results that can advance knowledge in the field.

Autor em destaque: Avançando na pesquisa hematopoiética usando isolamento de células estromais para sequenciamento de células únicas

Here we present protocols that enable isolation of stromal cells from murine bone, bone marrow, thymus and human thymic tissue compatible with single-cell multiomics.

Isolamento de células estromais de órgãos hematopoiéticos

Single-cell sequencing has enabled the mapping of heterogeneous cell populations in the stroma of hematopoietic organs. These methodologies provide a lens ...

Isolamento e Transplante de diferentes envelhecidas murino tímicos enxertos.

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