INTRODUÇÃO: O objetivo deste estudo foi avaliar prospectivamente os anticorpos anti-HLA após o transplante renal e associar estes achados com episódios de rejeição aguda, marcação por C4d e sobrevida do enxerto. MÉTODOS: Foram avaliados 926 soros de 111 pacientes no primeiro ano pós-transplante ou até a perda do enxerto. Os anticorpos foram analisados por PRA-ELISA (Panel Reactive Antibodies by Enzyme Linked Immuno Sorbent Assay). Anticorpos anti-HLA doador-específicos foram detectados por provas-cruzadas e caracterizados pelo método de microesferas marcadas com antígenos HLA. Episódios de rejeição aguda foram classificados conforme os Critérios de Banff 97, atualizados em 2003. RESULTADOS: Conforme o PRA-ELISA pós-transplante os pacientes foram classificados em 5 Grupos: Grupo A (n=80): sem evidência de anticorpos pré e pós-transplante; Grupo B (n=8): pacientes com anticorpos de novo; Grupo C (n=5): pacientes sensibilizados que permaneceram com mesmo nível de PRA-ELISA; Grupo D (n=4): pacientes sensibilizados que elevaram o nível de PRA-ELISA e Grupo E (n=14): pacientes sensibilizados que diminuíram o nível de PRA-ELISA durante o primeiro ano pós-transplante. A incidência de rejeição aguda foi de 23,4%. Pacientes dos Grupos B, C e D apresentaram mais episódios de rejeição aguda (respectivamente, 57%; 60% e 100%) que os dos Grupos A (18%) e E (7%), (p<0,001). Rejeições ocorridas no Grupo A foram histologicamente menos severas do que as dos outros Grupos (p=0,03) e com menor incidência de C4d+ (p<0,001). Entre os pacientes com rejeição aguda, 44% deles apresentaram anticorpos no momento da rejeição, sendo que em 90% dos casos esses anticorpos foram doadorespecíficos. Rejeição mediada por células, ou seja, sem anticorpos e com C4d-, ocorreu em 56% dos casos. A incidência global de rejeição mediada por anticorpos (RMA) foi de 11%. A sobrevida do enxerto censurada para óbito foi menor em pacientes com rejeição aguda (p<0,001), especialmente naqueles com anticorpos anti-HLA doador-específicos (p<0,001), com C4d+ (p=0,003) e nos casos de RMA (p<0,003). CONCLUSÃO: Nossos dados sugerem que a monitorização dos anticorpos anti-HLA após o transplante renal pode ser útil no diagnóstico das respostas mediadas por anticorpos e tem implicações em termos de sobrevida do enxerto. / INTRODUCTION: The aim was to follow prospectively anti-HLA antibodies (Abs) after kidney transplantation and to evaluate their association with acute rejection episodes, C4d staining and graft survival. METHODS: We analyzed 926 sera from 111 transplanted patients until graft lost or during 1 year posttransplant. The antibodies were analyzed using Panel Reactive Antibodies by Enzyme Linked Immuno Sorbent Assay (PRA-ELISA). Donor-specific antibodies (DSA) were detected by crossmatch tests and characterized by single antigen beads. Acute rejections (AR) were classified by Banff 97 criteria, updated in 2003. RESULTS: According to post-transplant PRAELISA the patients were classified in 5 groups: Group A (n=80): no evidence of Abs pre and post-transplant; Group B (n=8): patients with Abs de novo; Group C (n=5): sensitized patients who sustained the same PRA-ELISA levels; Group D (n=4): sensitized patients who increased PRA-ELISA levels and Group E (n=14): sensitized patients who decreased PRA-ELISA levels during the first year. The overall incidence of acute rejection was 23,4%. Patients from Groups B, C and D had more AR (respectively, 57%; 60% and 100%) than patients from Groups A (18%) and E (7%), (p<0.001). Patients from Group A had lower Banff scores than other groups (p=0.03) and lower rates of C4d positivity on AR biopsies (p<0.001). Among patients with AR, 44% of them had antibodies which appeared/increased during the AR episodes, and 90% were DSA. AR were pure cell-mediated (C4d-/Abs-) in 56% of the cases. The overall incidence of antibody-mediated rejection (AMR) was 11%. One-year censored graft survival was lower in patients with AR (p<0.001), specially in those with DSA (p<0.001), C4d+ (p=0.003), and AMR (p<0.003). CONCLUSION: Our data suggest that monitoring of anti- HLA antibodies post-transplantation is an useful tool for the diagnosis of antibody-mediated responses, and has prognostic implications in terms of graft survival.

Introdução: A nefropatia crônica do enxerto permanece sendo a principal causa de perda tardia de enxertos renais. No momento, não existe uma estratégia terapêutica definida para minimizar ou reverter a perda da função renal. Diversas tentativas terapêuticas foram empregadas sem resultados definitivos. As estratégias de minimização de inibidores da calcineurina (CNI) com conversão para Micofenolato mofetil (MMF) e conversão para Sirolimo (SRL) são as mais promissoras. Este estudo avaliou a segurança e a eficácia dessas duas estratégias terapêuticas na progressão da nefropatia crônica do enxerto em pacientes transplantados renais. Métodos: Foram selecionados pacientes com filtração glomerular (RFG) medida por depuração de 51Cr-EDTA entre 25 e 60 ml/min/1,73 m2 que apresentaram alterações histológicas compatíveis com nefropatia crônica do enxerto e que não apresentaram proteinúria 24 h superior a 800 mg/24 h. Os pacientes foram randomizados para serem convertidos ao SRL ou manterem-se sob níveis baixos de CNI associados ao MMF e prednisona. O objetivo primário foi avaliar um objetivo composto pelos seguintes eventos: morte, perda do enxerto, rejeição aguda ou perda de RFG inicial superior a 20%. Os pacientes foram acompanhados por 12 meses e a uma análise por intenção de tratar foi realizada ao fim desse período. Resultados: Vinte e nove pacientes foram randomizados para os grupos SRL (n=14) e CNI (n=15). Não houve diferença entre os grupos quanto a os dados demográficos e imunológicos. Os valores de creatinina sérica e a TFG foram semelhantes no momento da randomização. A sobrevida dos pacientes e dos enxertos foi de 100%. Não foram observados episódios de rejeição aguda. Após 12 meses, não houve diferença significativa entre os grupos com relação à TFG. Houve maior número de eventos adversos não-graves no grupo SRL, destacandose, acne, edema, piora de dislipidemia e anemia. Entretanto, o número de eventos adversos graves não foi estatisticamente diferente entre os grupos. SRL foi descontinuado temporariamente em 1 paciente, mas não ocorreu descontinuação definitiva no estudo. Conclusão: Os dois esquemas terapêuticos apresentaram desempenhos rigorosamente semelhantes com relação à evolução da função renal e quanto à evolução histológica, mas houve um número maior de eventos adversos não-graves com o uso de sirolimo / Chronic allograft nephropathy is the main cause of late kidney graft loss. Several treatments have been proposed for this condition without conclusive results. Calcineurin inhibitors minimization and conversion to Sirolimus are the most promising alternatives. This study evaluated the safety and the efficacy of these therapeutic strategies on one-year progression of chronic allograft nephropathy in kidney transplant recipients. Patients with measured glomerular filtration rate (51Cr-EDTA plasmatic clearance) between 25 e 60 ml/min/1,73 m2 and histological findings of CAN, with proteinuria less than 800 mg/24 h were included. They were randomized either to Sirolimus or to low-level of CNI (both groups received MMF and prednisone). The primary end-point was a composite of first occurrence of death, graft loss, acute rejection or a 20% decrease of initial GFR. Patients were followed for 12 months and evaluated as intention-to-treat analysis. Twenty-nine patients were included in this study. Fourteen patients were randomized to SRL group and fifteen to CNI group. At baseline, no differences were detected in any of the demographic and immunologic group characteristics. Also, serum creatinine and GFR were not different at randomization. One year after conversion, patient and graft survival was 100%. At 12 months, there were no differences in GFR between two groups, in SRL group was 41,99 ± 13,48 ml/min/1,73 m2and in CNI group was 41,21 ± 9,10 ml/min/1,73 m2 (p=0,96). Non-serious adverse events, like anemia (p=0,006), acne (p=0,006), edema (p=0,005) and mouth ulcers (p=0,017) were more frequently found in the SRL group. No significant difference in serious adverse events was observed. SRL was temporarily interrupted in one patient. None of the patients dropped-out from the study and none required study drug discontinuation. In conclusion both regimens conferred equal beneficial in GFR preservation in CAN patients. However, SRL was associated with more adverse events

Introdução: O transplante renal é a terapia substitutiva de escolha para a insuficiência renal crônica. O número absoluto de transplantes renais vem aumentando mundialmente e consequentemente as complicações deste procedimento têm sido evidenciadas com maior recorrência, dentre elas a estenose na artéria renal transplantada. A técnica endovascular vem mostrando bons resultados iniciais, com boa taxa de perviedade e baixa taxa de complicações pósoperatórias quando comparadas a técnica aberta para tratamento da estenose. O objetivo deste estudo foi avaliar os resultados primários da angioplastia da artéria renal do rim transplantado secundário a processo de re-estenose. Métodos: Realizado estudo retrospectivo no período de setembro de 2009 a outubro de 2015, baseado em protocolos de seguimento pós-transplante com perfil dos pacientes submetidos a tratamento por estenose em artéria de rim transplantado e o seguimento em curto prazo com critérios clínicos, laboratoriais e ultrassonográficos. Resultados: Dentre um total de 391 transplantes, 19 pacientes foram diagnosticados com Estenose na Artéria renal transplantada. Evidenciado um tempo médio entre o transplante e o diagnóstico de 172,6 dias. As estenoses ou acotovelamentos com alterações hemodinâmicas foram evidenciadas na anastomose (47%), no terço proximal (35%) e terço médio (18%) da artéria transplantada. Todos os pacientes foram submetidos a angioplastia com balão e posicionamento de stent metálico com sucesso técnico de 94,7 %. A creatinina média evoluiu de 3,63 mg/dl para 2,69 mg/dl em 24h e para 1,81 mg/dl em 30 dias (p<0.05). A taxa de filtração glomerular melhorou de 32,66 ml/min para 41,61 ml/min após 24 horas e 51,05 ml/min após 30 dias (p<0.05). Os critérios ultrassonográficos avaliados de velocidade da artéria renal e índice reno-iliaco (368,9 cm/seg e 3,71 pré angioplastia) normalizaram e se estabilizaram durante o período estudado (211,45 cm/seg e 1,69 90 dias pós angioplastia; p<0.05). Conclusão: A abordagem endovascular utilizando de angioplastia primária e colocação de stent metálico foi segura com boa uma taxa de sucesso técnico. O procedimento foi efetivo na melhora da função renal do enxerto transplantado e na correção das alterações ultrassonográficas evidenciadas no pré-operatório. / Introduction: Renal transplantation is the substitutive therapy of choice for chronic renal failure. The absolute number of renal transplants has increased worldwide and consequently the complications of this procedure have been evidenced with greater recurrence, among them stenosis in the transplanted renal artery. The endovascular technique has shown good initial results, with good patency rate and low rate of postoperative complications when compared to the open technique for stenosis treatment. The aim of this study was to evaluate the primary results of ATP from the renal artery of the transplanted kidney secondary to the restenosis process. Methods: A retrospective study was carried out from September 2009 to October 2015, based on post-transplant follow-up protocols with a profile of patients submitted to stenosis in a transplanted kidney artery and a short-term follow-up with clinical, laboratory and ultrasonographics criteria. Results: Out of a total of 391 transplants, 19 patients were diagnosed with transplanted renal artery stenosis. An average time between transplantation and the diagnosis of 172.6 days was evidenced. Stenting or flexing with hemodynamic changes were evident in the anastomosis (47%), in the proximal third (35%) and the middle third (18%) of the transplanted artery. All patients underwent balloon angioplasty and metallic stent placement with technical success of 94.7%. Mean creatinine increased from 3.63 mg / dL to 2.69 mg / dL in 24 hours and to 1.81 mg / dL in 30 days (p <0.05). The glomerular filtration rate improved from 32.66 ml / min to 41.61 ml / min after 24 hours and 51.05 ml / min after 30 days (p <0.05). The ultrasound criteria evaluated for renal artery velocity and reno-iliac index (368.9 cm / sec and 3.71 pre angioplasty) normalized and stabilized during the study period (211.45 cm / sec and 1.69 Angioplasty, p <0.05). Conclusion: The endovascular approach using primary angioplasty and stent placement was safe with good technical success rate. The procedure was effective in improving the renal function of the transplanted graft and in correcting the ultrasound changes evidenced in the preoperative period.

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-10-11T13:25:57Z No. of bitstreams: 1 flavialiciarodriguesmagacho.pdf: 2211542 bytes, checksum: 17ff2c88b41d6fd8f0a559f9d79f8d7e (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-10-16T13:58:49Z (GMT) No. of bitstreams: 1 flavialiciarodriguesmagacho.pdf: 2211542 bytes, checksum: 17ff2c88b41d6fd8f0a559f9d79f8d7e (MD5) / Made available in DSpace on 2018-10-16T13:58:49Z (GMT). No. of bitstreams: 1 flavialiciarodriguesmagacho.pdf: 2211542 bytes, checksum: 17ff2c88b41d6fd8f0a559f9d79f8d7e (MD5) Previous issue date: 2018-07-12 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Introdução: a doença renal crônica destaca-se por afetar a vida de milhares de brasileiros e onerar os cofres públicos. Na fase terminal da doença, a sobrevivência do paciente é condicionada à realização de um tipo de terapia renal substitutiva. A literatura tem demonstrado ser o transplante renal a alternativa custo-efetiva dentre as terapias renais substitutivas, pois permite a reintegração do paciente às suas atividades cotidianas, aumentando a expectativa e qualidade de vida. Um fator que tem contribuído para o sucesso dos transplantes renais é o avanço tecnológico dos imunossupressores. Recomenda-se para o tratamento de manutenção dos transplantes renais a administração de esquemas tríplices de medicamentos, compostos por um esteroide mais dois medicamentos de classes farmacológicas distintas (inibidores da calcineurina ou antimetabólitos ou inibidores da rapamicina). Objetivo: avaliar o custo-efetividade da administração de tacrolimo com micofenolato de sódio e Prednisona (Grupo 1= 93 pacientes) comparado com a associação de tacrolimo com everolimo e Prednisona (Grupo 2= 91 pacientes), no tratamento de manutenção pós-transplante renal, em uma Unidade de Prática Integrada do Hospital Santa Casa de Misericórdia de Juiz de Fora, Minas Gerais. Material e métodos: para a análise farmacoeconômica dos esquemas imunossupressores foi utilizado o modelo estático, do tipo Árvore de Decisão. O modelo foi desenvolvido no software Treeage Suite 2011 e acompanhou uma coorte de pós-transplantados renais, estimando os benefícios clínicos em termos de sobrevida e incidência de eventos adversos (rejeição, doença/infecção por citomegalovírus, perda do enxerto e morte), bem como os custos associados aos regimes imunossupressores, na perspectiva do Sistema Único de Saúde. Resultados: a supremacia do everolimo em relação ao micofenolato de sódio se fez presente principalmente nos eventos relacionados à incidência de pacientes que apresentaram infecção ou doença decorrente por citomegalovírus (4,4% com everolimo versus 20,4% com micofenolato de sódio, p = 0,001). Na análise considerando sobrevida como desfecho, o Grupo 2 não pode ser considerado custo-efetivo quando comparado ao uso de Grupo 1, pois a razão de custo-efetividade incremental foi cerca de R$229.876,30, excedendo o limiar de custo-efetividade recomendado pela Organização Mundial da Saúde, três vezes o produto interno bruto brasileiro. Já na análise que diz respeito à incidência de eventos adversos, a razão de custo-efetividade incremental foi cerca de R$52.760,52, portanto, o Grupo 2 foi considerado custo-efetivo em relação ao Grupo 1. Conclusão: o regime imunossupressor contendo ácido micofenólico é ainda considerado o padrão-ouro para o tratamento de manutenção do transplante renal, no entanto, está associado a muitos efeitos adversos para os transplantados. Esse estudo desmistifica tal regime, à medida que o regime imunossupressor contendo everolimo apresentou-se custo-efetivo em relação ao micofenolato na análise feita a partir da incidência de efeitos adversos, bem como na redução significativa de eventos relacionados ao citomegalovírus, o qual é responsável pela maior causa de morbimortalidade em transplantados. / Introduction: chronic kidney disease stands out as affecting the lives of thousands of Brazilians and burdening the public coffers. In the terminal phase of the disease, the survival of the patient is conditioned to a type of substitutive renal therapy. The literature has demonstrated that kidney transplantation is the cost-effective alternative among the substitutive renal therapies, since it allows reintegration of the patient into their daily activities, increasing the expectation and quality of life. One factor that has contributed to the success of kidney transplantation is the technological advancement of immunosuppressants. The administration of three-drug regimens consisting of a steroid plus two drugs of different pharmacological classes (calcineurin inhibitors or antimetabolites or inhibitors of rapamycin) is recommended for the maintenance treatment of kidney transplantation. Aim: to evaluate the cost-effectiveness of administration of tacrolimus with mycophenolate sodium and prednisone (Group 1 = 93 patients) compared to the combination of tacrolimus with everolimus and Prednisone (Group 2 = 91 patients) in post-transplant renal maintenance, in an Integrated Practice Unit of the Santa Casa de Misericórdia Hospital of Juiz de Fora, Minas Gerais. Material and methods: for the pharmacoeconomic analysis of the immunosuppressive regimens, the static model, of the decision tree type, was used. The model was developed in the Treeage Suite 2011 software and followed a cohort of renal transplant recipients, estimating the clinical benefits in terms of survival and incidence of adverse events (rejection, cytomegalovirus disease / infection, graft loss and death), as well as the costs associated with immunosuppressive regimens, from the Unified Health System perspective. Results: the efficacy of everolimo in relation to mycophenolate sodium was mainly present in the events related to the incidence of patients who presented infection or disease due to cymegalovirus (4.4% with everolimo versus 20.4% with mycophenolate sodium, p = 0.001). In the analysis considering survival as an outcome, Group 2 can not be considered cost-effective when compared to Group 1 use, as the incremental Cost-Effectiveness Ratio was around R$229,876.30, exceeding the cost thresholdeffectiveness recommended by the World Health Organization, three times the Brazilian GDP. In the analysis related to the incidence of adverse events, the ICR was around R$52,760.52, therefore, Group 2 was considered cost-effective in relation to Group 1. Conclusion: the immunosuppressive regimen containing mycophenolic acid is still considered the gold standard for the maintenance treatment of kidney transplantation, however, is associated with many adverse effects for transplant recipients. This study demystifies this regimen, as the immunosuppressive regimen containing everolimo was cost-effective in relation to mycophenolate in the analysis made from the incidence of adverse effects, as well as in the significant reduction of events related to citamegalovirus, which is responsible the greatest cause of morbidity and mortality in transplant patients.

Parmi toutes les études/cohortes existantes en transplantation rénale, peu d’entre elles étudient l’impact des paramètres pharmacologiques. L’utilisation d’un auto-questionnaire, en complément du dossier médical, a été validée pour le recueil de ces données. La comparaison du dossier médical et des auto-questionnaires pour la déclaration des événements indésirables a permis de mettre en évidence des différences. Les infections étaient les événements indésirables les plus déclarés par les médecins alors que les patients n’en déclaraient que très peu. L’observance, évaluée par l’auto-questionnaire, diminuait entre la 1ère et la 3ème année post-greffe, tout comme la sensation d’euphorie et de renaissance. En effet, le score de qualité de vie (QdV) de la dimension « Santé mentale » du ReTransQol diminuait entre ces deux périodes. En revanche, la peur de la perte du greffon du patient augmentait comme démontrée par la diminution du score de QdV de la dimension « Peur de la perte du greffon ». La QdV, évaluée par des questionnaires génériques ou spécifiques aux greffés rénaux, est aussi un paramètre important à prendre en compte dans le suivi des patients. Les propriétés psychométriques de la 2nde version du ReTransQol, ainsi que sa reproductibilité et sa sensibilité aux changements ont été validées dès le 3ème mois post-transplantation rénale. L’étude de pharmaco-économie Ephegren, suite de la cohorte Epigren, va notamment étudier les rapports coût-efficacité et coût-utilité des stratégies immunosuppressives et anti-cytomégalovirus. Ainsi, des recommandations pourront être proposées afin d’homogénéiser les pratiques et diminuer les coûts de prise en charge des greffés rénaux. / Among all existing studies/cohorts in kidney transplantation, only a few study the impact of the pharmacological parameters. In addition to the clinical file, the use of a self-administered questionnaire has been validated to collect these data. Comparison between clinical file and self-administered questionnaire concerning the reporting of adverse events highlighted some differences. Infections were the most reported adverse events by the physicians while the patients declared only a few. Adherence evaluated with the self-administered questionnaire decreased between the first and third post-transplantation year and so did the feeling of euphoria and revival. The « Mental health » dimension of the quality of life (QOL) ReTransQol score decreased over this period. However patients’ fear of losing the graft increased as shown by the decrease of the « Fear of losing the graft » dimension of the QOL score. QOL, evaluated by generic and kidney-transplanted-specific questionnaires is also an important parameter that must be considered in patient follow-up. Psychometric properties of the second version of the ReTransQol, as well as its reproducibility and its sensitivity to changes have been validated as early as the 3rd post-kidney-transplantation month. The pharmacoeconomic study Ephegren, development of Epigren cohort, will study the cost-effectiveness and cost-utility ratio of immunosuppressive and anti-cytomegalovirus strategies. Guidelines will then be proposed to standardise the treatments and decrease the management costs of kidney-transplant recipients.

African Americans (AA) are more susceptible to end-stage renal disease (ESRD) for several reasons. Treatment options for patients with ESRD include dialysis therapy and transplantation, with the latter typically producing better outcomes. AA are less likely to complete the medical evaluation process, which requires patients to consult with doctors and undergo a series of tests and examinations. This study sought to determine the factors that predict completion of the medical evaluation for AA ESRD patients using a mixed methods design. Participants consisted of transplant professionals (N=23) recruited from nine transplant centers in the Mid-Atlantic, Mid-Western and Southeastern parts of the United States, and kidney patients (N=30 patients) recruited from one transplant center in the Mid-Atlantic region. Semi-structured interviews and nominal focus groups were conducted to gather qualitative data; quantitative survey data were also collected. The results revealed factors classified as impacting patients at the individual-level and systemic level, and others classified as health-related and informational/educational. Participants ranked insurances issues, limited income, lack of a personal means of transportation, lack of patient motivation, the number of procedures required to complete the evaluation, scheduling difficulties and time constraints as top barriers to completing the medical evaluation process. Top motivators consisted of informational support, social support, religious beliefs, patients’ desire to get off dialysis, support from the transplant staff, center-based education, patient’s knowledge of the benefits of transplantation and patient navigators. These findings provide valuable information on factors that impact AA renal patients’ completion of the medical evaluation.

Background: We evaluated the concept of whether liver failure patients with a superimposed kidney injury receiving a simultaneous liver and kidney transplant (SLKT) have similar outcomes compared to patients with liver failure without a kidney injury receiving a liver transplantation (LT) alone. Methods: Using data from the United Network of Organ Sharing (UNOS) database, patients were divided into five groups based on pre-transplant model for end-stage liver disease (MELD) scores and categorized as not having (serum creatinine (sCr) <= 1.5 mg/dL) or having (sCr > 1.5 mg/dL) renal dysfunction. Of 30,958 patients undergoing LT, 14,679 (47.5%) had renal dysfunction, and of those, 5,084 (16.4%) had dialysis. Results: Survival in those (liver failure with renal dysfunction) receiving SLKT was significantly worse (P < 0.001) as compared to those with sCr < 1.5 mg/dL (liver failure only). The highest mortality rate observed was 21% in the 36+ MELD group with renal dysfunction with or without SLKT. In high MELD recipients (MELD > 30) with renal dysfunction, presence of renal dysfunction affects the outcome and SLKT does not improve survival. In low MELD recipients (16 - 20), presence of renal dysfunction at the time of transplantation does affect post-transplant survival, but survival is improved with SLKT. Conclusions: SLKT improved 1-year survival only in low MELD (16 - 20) recipients but not in other groups. Performance of SLKT should be limited to patients where a benefit in survival and post-transplant outcomes can be demonstrated.

Le cytomégalovirus (CMV) est l’agent responsable de l’infection opportuniste la plus fréquemment rencontrée en transplantation d’organe. Chez les receveurs séronégatifs qui reçoivent un rein provenant d’un donneur séropositif, 50 % de ces patients peuvent développer une virémie, et 30 % une maladie. A court terme, malgré les traitements anti-viraux, elle est responsable d’une morbidité non négligeable. A long terme, le CMV est associé à une augmentation de la fréquence des sténoses artérielles, plus d’infections associées, plus de rejet aigu, plus de lésions de fibrose interstitielle et d’atrophie tubulaire, une moins bonne survie des greffons et des patients. La cohabitation et la coévolution du CMV avec l’homme depuis des milliers d’années ont aboutie à un état d’équilibre entre le virus et son hôte. Le virus s’est profondément adapté à son hôte afin d’échapper à la réponse immune. En réponse à cela, la réponse immunitaire anti-CMV occupe une part unique et majeure au sein de la réponse immune de l’hôte. Les lymphocytes T CD8+ spécifiques du CMV représentent par exemple 10.2% des lymphocytes T CD8+ mémoires. Avec l’âge, ils s’accumulent et peuvent représenter jusqu’à 30% du pool total de lymphocyte T CD8+. Le système immunitaire sous la contrainte du virus s’est donc refaçonné de façon à garder le contrôle du virus. Depuis 1999, un nouvel acteur de cette réponse immunitaire a été identifié : les lymphocytes T gamma delta Vdelta2-negative. Ces cellules sont impliquées habituellement dans la lutte contre les différents stress d’origine microbien et non microbien (tumeur). Elles interviennent plutôt localement (dans les épithéliums) par différents mécanismes et sont désormais considérées comme des effecteurs intermédiaires entre l’immunité innée et l’immunité adaptative. Leur expansion dans le sang est associée à la guérison de la maladie et à la résolution de l’infection à CMV. Elles ont par ailleurs in vitro une réactivité croisée contre des cellules infectées par le CMV et des cellules tumorales. Les lymphocytes T gamma delta Vdelta2-negative sont donc une représentation supplémentaire de l’énorme impact du CMV sur le système immunitaire de l’hôte. Dans ce travail, nous avons pu étendre et approfondir leur rôle en transplantation d’organe. Nous avons tout d’abord décrit que les lymphocytes T gamma delta Vdelta2-negative avaient un phénotype et une cinétique d’expansion exactement superposable aux lymphocytes T CD8+ spécifiques du CMV in vivo. Nous avons ensuite observé que l’expansion des lymphocytes T gamma delta Vdelta2-negative induits pas l’infection à CMV s’associait à une survenue moindre de cancer à long terme chez les patients transplantés rénaux. Nous avons pu montrer que leur activation était sous la dépendance d’une interaction entre leur TCR et un ligand. Enfin, une autre voie d’activation dépendante du CD16, faisant intervenir les complexes immuns CMV-IgG anti-CMV a aussi été identifiée. Nos travaux depuis 10 ans ont donc démontré que les lymphocytes T gamma delta Vdelta2-negative occupaient une place majeure dans la réponse immune anti-CMV au même titre que les lymphocytes T CD8+. L’intégration de ces cellules à l’immunologie anti-CMV devrait permettre de mieux comprendre certains effets indirects induits par le virus, et pourrait être utile dans le suivi de la réponse immune anti-CMV en transplantation d’organe. L’identification de leur ligand pourrait permettre enfin de tester assez rapidement de nouveaux protocoles d’immunothérapie anti-virale ou anti-tumorale. / Cytomegalovirus (CMV) infection is the most frequent opportunistic infection encountered in solid-organ transplantation. Fifty percent of seronegative kidney transplant recipients (KTR) who receive a kidney from a seropositive donor may develop a CMV infection which causes a disease in 30% of cases. In the long term, CMV is associated with an increased incidence of arterial stenosis, more opportunistic infections, more acute rejection episodes, more interstitial fibrosis and tubular atrophy, and a poorer graft and patient survivals. For thousands years, the co-evolution between the CMV and the immune system allowed to a state of equilibrium between the virus and the host. The virus has deeply adapted to its host in order to escape the immune response. In response, the anti-CMV immune reaction takes up an important and unique place. For example, the CMV-specific CD8+ T cells represent an average 10.2% of the memory CD8+ T cell compartment in CMV-seropositive healthy individuals. With age, these cells accumulate and can represent around 30% of CD8+ T lymphocytes. Therefore under the long-lasting pressure of the virus, the immune system has redesigned in order to keep the control of the virus. Since 1999, a new actor was identified within the immune system: the Vdelta2-negative gamma delta T cells. These cells are involved against various microbial and non microbial stresses. They act locally in epithelia by different mechanisms and are now considered as intermediate effectors between innate and adaptive immunity. In vivo in KTR, their blood expansion is associated with the resolution of CMV infection. In vitro, they share a cross-reactivity against CMV-infected cells and tumor cells. Therefore, the Vdelta2-negative gamma delta T cells are new representatives of the huge impact of CMV on the host immune system. In this work, we were able to extend and get further insight into their role in organ transplantation. In vivo, we first described that Vdelta2-negative gamma delta T cells displayed a phenotype and an expansion kinetic similar to that of CMV-specific CD8+ T cells. Next, we observed that the CMV-induced Vdelta2-negative gamma delta T cells expansion was associated with a lower occurrence of cancer in long-term KTR. In vitro, experiments of transfer of gamma delta TCR allowed us to show that their activation against tumor ligands was TCR-dependent and that different tumor ligands could be recognized by each Vdelta2-negative gamma delta TCR studied. In addition, we observed that the recognition of CMV-infected cells was not only TCR-dependent, but under the dependence of a multi molecular complex involving co stimulatory signals. Finally, we also identified a new CD16-dependent pathway of activation in gamma-delta T cells, involving IgG-opsonised CMV. In summary, Vdelta2-negative gamma delta T cells take up a major place within the anti-CMV immune response in addition to CD8+ T lymphocytes. The integration of these cells to the anti-CMV immunology should provide a better understanding of some indirect effects of the virus and could be useful to monitor the immune response against CMV in solid-organ transplant recipients. Moreover, identification of their ligands could provide interesting tools for new protocols of anti-CMV and anti-tumor immunotherapy.

Introdução: o transplante renal é o tratamento de escolha para uma significativa porção dos pacientes com perda crônica terminal da função renal. A rejeição aguda é uma importante complicação pós-transplante e entre outras disfunções agudas tem na biópsia do enxerto o padrão ouro para o seu diagnóstico. No entanto as biópsias apresentam uma série de limitações e riscos sendo necessário que se desenvolva biomarcadores não invasivos capazes de identificar disfunções do enxerto. Objetivos: analisar e quantificar a expressão dos microRNAs miR-142-3p, miR-155 e miR-210 em amostras de sangue periférico, urina e tecido renal coletadas de pacientes que submetidos à transplante renal que desenvolveram disfunção do enxerto. Métodos: estudo com delineamento transversal e executado no Laboratório de Biologia Molecular aplicado à Nefrologia (LABMAN), do Centro de Pesquisa Experimental do Hospital de Clínicas de Porto Alegre. As amostras são de pacientes submetidos a transplante renal que necessitaram de biópsia, por critério clínico. A expressão dos miRNAs miR-142-3p, miR-155 e miR-210 nos materiais biológicos (tecido renal, sangue periférico e células do sedimento urinário) foi avaliada através da técnica de reação em cadeia da polimerase quantitativo em tempo real. Resultados: foi encontrada, no sangue periférico uma diminuição estatisticamente significativa na expressão do miR-142-3p no grupo de pacientes com rejeição aguda (n=23) quando comparado ao grupo com outras causas de disfunção do enxerto (n=68) (P = 0,01). Não houve diferença entre os grupos na expressão do miR-155 e do miR-210, tampouco para o miR142-3p nos demais compartimentos. Conclusão: miR-142-3p mostra uma expressão diferenciada de rejeição aguda de enxertos renais, há um envolvimento deste marcador no grupo de biomarcadores moleculares em potencial para a disfunção do enxerto renal. / Background: kidney transplantation is the treatment of choice for a significant portion of patients with end-stage kidney disease. Acute rejection is a major post-transplant complication among other acute disorders and has on graft biopsy the gold standard for diagnosis. Biopsy, however it is an invasive and potentially harmful procedure so it is desirable to develop new noninvasive markers for diagnosing graft dysfunction. Objective: to analyze and quantify the expression of microRNAs miR-142-3p, miR-155 and miR-210 in the peripheral blood, urinary sediment and kidney tissue obtained from patients who developed graft dysfunction after kidney transplantation. Methods: crosssectional study performed at the Laboratory of Molecular Biology applied to Nephrology (Labman), Center of Experimental Research from Hospital de Clinicas de Porto Alegre. The samples are from kidney transplant patients who undertook indication biopsies as a part of investigation of graft dysfunction. Micro-RNAs expression was evaluated by quantitative real-time polymerase chain reaction. Results: it was found that in peripheral blood, a significant decrease in the expression of miR-142-3p occurred in patients with acute rejection (n = 23) as compared to the group of patients with other causes of graft dysfunction (n = 68), (P = 0.01). No other significant differences were found in gene expression of miR-155 and miR-210, neither for miR142-3p in the other urine or kidney tissue. Conclusion: miR-142-3p presents differential expression in the peripheral blood of patients with rejecting kidney grafts. The role of miRNAs as biomarkers for kidney graft dysfunction is worth be further explored.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-01-11T16:56:50Z No. of bitstreams: 1 lucianesenradesouzabraga.pdf: 2197940 bytes, checksum: 0ad10886dccd0f71b9cda0d9562287bd (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-01-25T17:09:45Z (GMT) No. of bitstreams: 1 lucianesenradesouzabraga.pdf: 2197940 bytes, checksum: 0ad10886dccd0f71b9cda0d9562287bd (MD5) / Made available in DSpace on 2016-01-25T17:09:45Z (GMT). No. of bitstreams: 1 lucianesenradesouzabraga.pdf: 2197940 bytes, checksum: 0ad10886dccd0f71b9cda0d9562287bd (MD5) Previous issue date: 2015-04-19 / Desde o primeiro transplante renal bem sucedido, que a clínica vêm sendo monitorada, medida e descrita, de forma a nortear a atividade transplantadora em todo o mundo. Neste trabalho, avaliamos dados de prontuário médico de todos os pacientes transplantados renais entre janeiro de 2002 e dezembro de 2012, acompanhados no Núcleo Interdisciplinar de Estudos e Pesquisas em Nefrologia da Universidade Federal de Juiz de Fora (NIEPEN-UFJF). Este estudo, retrospectivo e de coorte, foi idealizado a partir da coleta de dados para alimentação do Cadastro Nacional de Transplantes (CNTx), tendo como objetivo principal descrever a sobrevida de pacientes e do enxerto renal, bem como o impacto de diferentes variáveis clínicas sobre estes desfechos, em um serviço de baixa atividade transplantadora. Foram incluídos 162 pacientes, com média de idade de 44 ± 11,5 anos, dos quais 92% tiveram doador vivo relacionado. A sobrevida dos pacientes, do enxerto e do enxerto censurada para óbito foram analisadas através do método de Kaplan-Meier, e sua associação com os fatores de risco estudados foi verificada por meio do teste log-rank, ou pelo modelo de Cox, conforme indicado. A sobrevida dos pacientes em 1, 3 e 5 anos foi de 88,6%, 86% e 82,9%, respectivamente. A sobrevida do enxerto foi de 86,9%, 83% e 77%, e a sobrevida do enxerto censurada para óbito foi de 98,1%, 96,6% e 92,9% para os mesmos períodos. A maioria das perdas de enxerto ocorreram durante o primeiro ano pós-transplante, devido a infecções. Após ajustes estatísticos, observamos que pacientes com idade acima de 42 anos (HHR 3,94, IC 1,39 a 11,13), com doador falecido (HHR 11,41, CI 1,2 a 108,35) ou escolaridade entre 8 e 11 anos apresentaram risco aumentado de perda do enxerto, de forma independente. Em resumo, apesar da elevada mortalidade observada no primeiro ano pós-transplante, as taxas de sobrevida de pacientes e do enxerto foram similares àquelas descritas em grandes bases de dados preexistentes. Acreditamos que a melhoria do cuidado no período pós-transplante é fundamental no sentido de melhorar as taxas de sobrevida, especialmente em centros de baixa atividade transplantadora, que correspondem a cerca de 30% da atividade transplantadora nacional, mas representam enorme potencial para crescimento do número absoluto de transplantes no Brasil, nos próximos anos. / Since the first successful kidney transplant, performance data have been monitored, measured and reported in order to guide transplant activity worldwide. In this paper, we evaluated clinical data from medical records of all kidney transplant recipients followed at the Núcleo Interdisciplinar de Estudos e Pesquisas em Nefrologia of the Federal University of Juiz de Fora (NIEPEN-UFJF), from January 2002 to December 2012. This is a retrospective cohort study, first conceived from periodical data feeding of the Brazilian National Transplant Control Database (CNTx). The main goal was to describe patient and graft survival, as well as clinical and demographic variables affecting them, in the setting of a low activity transplant center. We studied 162 patients, with a mean age of 44 ± 11.5 years, and 92% had a living donor. Patient, graft and death-censored graft survival rates were assessed by Kaplan-Meier analysis, and their association with the studied risk factors was assessed through log-rank test, or Cox model, as suitable. Patient survival at 1, 3 and 5 years was 88.6%, 86% and 82.9%, respectively. Graft survival was 86.9%, 83% and 77%, and death-censored graft survival was 98.1%, 96.6% and 92.9% for the aforementioned time points. Most grafts were lost due to patient death caused by infections, which mainly occurred within the first posttransplant year. After statistical adjustments, we observed that age over 42 years (HHR 3.94, CI 1.39 to 11.13), deceased donor (HHR 11.41, CI 1.2 to 108.35) and schooling time between 8-11 years were independently associated with graft loss. In summary, despite a high early mortality rate, patient and graft survival rates we observed are similar to those described in large databases. We believe that improvements in long-term posttransplant care are a key issue to improve survival rates, especially in low-activity transplant centers, which in Brazil account for roughly 30% of transplant activity, but also represent a great potential source of growth in number of transplants in years to come.