Devido à complexidade da insuficiência renal crônica e do seu tratamento, o transplante renal é, para a maioria dos pacientes, um acontecimento muito desejado. Atualmente, com o aumento do número de transplantes, observa-se também, com maior freqüência, o paciente que vivencia a experiência de ter que retornar ao tratamento dialítico após a perda do enxerto renal. O presente trabalho tem como proposta focalizar a pessoa com insuficiência renal crônica que já tenha realizado o transplante renal e, por algum motivo, tenha perdido o enxerto deparando-se, novamente, com a necessidade de realizar a hemodiálise para sobreviver. O objetivo é compreender, a partir da experiência vivida pelo paciente, como é para ele retornar a conviver com o tratamento dialítico após ter vivenciado um período sem necessitar desse tratamento. O trabalho fundamenta-se no método de pesquisa qualitativa de inspiração fenomenológica em Psicologia, que investiga a experiência humana vivida, e parte de uma questão orientadora: Como é para o paciente ter que retornar ao tratamento dialítico após ter ficado algum tempo transplantado e fora do programa de hemodiálise. Para tanto, foram entrevistados todos os oito pacientes que vivenciaram tal situação e que realizavam hemodiálise no Instituto de Hemodiálise da Santa Casa de Franca, SP. Por intermédio de entrevista fenomenológica, buscou-se chegar à experiência de cada paciente e apreender os significados atribuídos às suas vivências. Um diário de campo foi utilizado como fonte subsidiária de informação. As entrevistas foram analisadas por meio do método fenomenológico. Após a leitura atentiva de cada entrevista para apreensão de unidades de significado e, a partir das convergências dessas, foram desveladas as seguintes categorias: o transplante, subdividida em: o transplante como possibilidade: sonho e realidade, o transplante como experiência: a facticidade; a perda do transplante, que se subdividu em: o impacto da perda, a busca do sentido, a constatação da aprendizagem através da experiência; a volta a hemodiálise com as subcategorias: o começar de novo. a retomada do projeto existencial; e as fontes de apoio. Após a análise, foi realizada uma síntese compreensiva das vivências dos pacientes e, posteriormente, uma compreensão dessas vivências à luz da Psicologia Fenomenológica. Uma reflexão a respeito do cuidado a essas pessoas, levando em conta a dimensão subjetiva existencial que este olhar possibilita ftnalizou o presente estudo. / Due to the complexity of the chronic renal failure and its treatment, renal transplantation is, for the majority of patients, an event very desired. Currently, with the increase of the number of transplants, it is also observed, more frequently, the patient who lives the experience of having to return to the dialysis treatment dialítico after the loss of the renal graft. This work has the proposal focuses on the person with chronic renal failure who has already completed the renal transplantation and, for some reason, has lost the graft encountering, again, with the need to perform hemodialysis to survive. The objective is to understand, starting from the experience lived by the patient, as it is for him to return to live together with the treatment dialítico after having lived a period without needing of that treatment. The work is based on qualitative research method of phenomenological inspiration in Psychology, which investigates the human experience lived, and part of a guiding question: What is it like for the patient to have to return to dialysis treatment after having been a time transplanted and outside the hemodialysis program? For this, all of the eight patients, who experienced this situation and accomplished hemodialysis at the Institute of Hemodialysis of the Holy House of France, SP, were interviewed. By means of phenomenological interview, we tried to get the experience of each patient and apprehend the meanings attributed to their existences. A field diary was used as subsidiary source of information. The interviews were analyzed by means of the phenomenological method. After a careful reading of each interview for apprehension of units of meaning, and from the convergence of these, were discussed the following categories: the transplant, subdivided into: the transplant as a possible: dream and reality, the transplant as experience: the facticity; the loss of the transplant, which is subdivided into: the impact of the loss, the search for the sense, the verification of the learning through experience; the return to the hemodialysis with the subcategories: beginning again, the retaking of the existential project; and the support sources. After the analysis, a comprehensive synthesis of the patients\' existences was accomplished and, posteriorly, an understanding of these existences in the light of Phenomenological Psychology. A reflection on the care to these people, taking into account the subjective dimension existential that this look allows, concluded the present study.

Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-07-04T10:49:54Z No. of bitstreams: 1 anapaulasimoesferreirateixeira.pdf: 994054 bytes, checksum: 199eb1dc9ad02119d4f457cca728d665 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-08T14:04:54Z (GMT) No. of bitstreams: 1 anapaulasimoesferreirateixeira.pdf: 994054 bytes, checksum: 199eb1dc9ad02119d4f457cca728d665 (MD5) / Made available in DSpace on 2017-08-08T14:04:54Z (GMT). No. of bitstreams: 1 anapaulasimoesferreirateixeira.pdf: 994054 bytes, checksum: 199eb1dc9ad02119d4f457cca728d665 (MD5) Previous issue date: 2009-09-14 / Estudos evidenciam o aumento da prevalência da síndrome metabólica após o transplante renal e sugerem sua associação com a redução da função do enxerto e com o aumento do risco cardiovascular. Em nosso meio, não existem dados sobre a prevalência da síndrome metabólica após o transplante renal. O presente estudo tem por objetivos avaliar a prevalência da síndrome metabólica (SM) em receptores de transplante renal e identificar os fatores de risco associados ao seu diagnóstico. Realizado um estudo transversal, para obtenção de informações demográficas, clínicas e laboratoriais dos pacientes submetidos a transplante renal há mais de seis meses e em acompanhamento ambulatorial regular. A presença da síndrome metabólica foi determinada utilizando os critérios, atualizados em 2005, do National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATPIII). Foram incluídos 87 indivíduos, dos quais 39 (44,8%) preencheram critérios para a síndrome metabólica. Os pacientes com síndrome metabólica eram, em média, mais velhos (47,26 +/- 12,96 anos) do que aqueles sem SM (40,46+/- 10,57 anos). Após a análise multivariada, essa diferença de idade entre os grupos persistiu significante (p=0,009), implicando no risco incremental para SM de 5,5% para cada ano de vida (OR 1,055; IC 95% 1,014 a 1,098). De forma semelhante, o uso de betabloqueadores (p=0,01; OR 3,523, IC 95% 1,351 a 9,187) e a presença de diabetes mellitus pós-transplante (p<0,001) também se associaram à presença de síndrome metabólica Conclui-se que a prevalência de SM na população de transplantados renais em nosso meio é de 44,8%, superior à observada na população geral. O uso de betabloqueadores, a presença de diabetes mellitus pós-transplante e idade avançada se associaram à ocorrência de SM. / The prevalence of metabolic syndrome (MS) is increasing after renal transplantation and it has been associated to reduction in graft function and increase of cardiovascular risk. So far, there is no available data about MS after renal transplantation in Brazil. The aims of this study are to assess the prevalence of MS and its predisposing risk factors in recipients of renal transplantation. It is a transversal study that included patients with more than six months of renal transplantation. Demographic, clinical and laboratory data were obtained at the patients’s visit to the Clinic. Metabolic syndrome was characterized as proposed by the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATPIII) in its up date in 2005. Among the 87 patients included in the study, 39 (44.8%) had MS. Compared with the patients without MS, those with the syndrome were older, a finding that maintained significant after the multivariated analysis (OR 1.055; CI 95% 1.014 – 1.098, p=0.009), implicating a risk for MS of 5.5% for each year of life. Treatment with beta blockers OR 3.523; CI 95% 1.351 - 9.187, p=0.01) and the presence of post-transplant diabetes mellitus (p<0.001) was also associated with MS. In conclusion: The prevalence of MS in 44.8% of the patients studied is higher than that found in the general population and was associated with older age, post-transplant diabetes mellitus and treatment with beta blockers.

Orientador: Carlos Arturo Levi D'Ancona / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T07:14:10Z (GMT). No. of bitstreams: 1 Silva_DanielCarlosda_M.pdf: 1747195 bytes, checksum: f3a4238a53971be2f9795ab4204fa65d (MD5) Previous issue date: 2012 / Resumo: Objetvos: Avaliar com realização do estudo urodinâmico, a recuperação da função vesical em pacientes com doença renal crônica sem causa urológica de base com longos períodos de oligúria / anúria, submetidos a transplante renal. Pacientes e Métodos: De abril de 2009 a junho de 2010, 30 pacientes apresentando oligúria / anúria, foram prospectivamente avaliados com estudo urodinâmico. Este foi realizado imediatamente antes e seis meses após o transplante renal. Os critérios de inclusão foram: idade > 18 anos, doença renal crônica sem causa urológica envolvida na sua etiologia, tempo de diálise superior a 12 meses, nome em lista de transplante com doador falecido. Foram excluídos pacientes com alteração no ultrassom de vias urinárias, uretrocistografia miccional e urianálise e com diurese residual de 24 horas superior a 1000ml. Resultados: Observou-se completa recuperação da função vesical após o retorno da diurese, no sexto mês pós-transplante, independente de haver ou não disfuncionalização vesical. As variações nos parâmetros urodinâmicos foram: primeira sensação de enchimento vesical: 88,8 para 168,7ml (p = 0,0005); primeiro desejo miccional: 137,2 para 251,1ml (p <0,0001); capacidade cistométrica máxima: 221,2 para 428,7ml (p<0,0001); complacência vesical: 73,9 para 138,6ml/cm H2O (p =0,03) e fluxo máximo: 8,1 para 15,8ml/s (p <0,0001). O número de Abrams-Griffths nos homens reduziu de 31,8 para 15,2 (p =0,002). Não se observou mudanças significativas na pressão detrusora no fluxo máximo e resíduo pós-miccional. Pacientes com diurese residual de 24 horas menor que 200ml apresentaram alterações urodinâmicas significativamente maiores antes do transplante. Conclusão: Completa recuperação da função vesical foi observada nos pacientes sem doença urológica, seis meses após o transplante renal e retorno do débito urinário / Abstract: Purpose: To evaluate by urodynamic assessment, recovery of bladder function in patients with end stage renal disease without urological causes with long term oliguria, submitted to renal transplant. Patients and Methods: From April 2009 to June 2010, 30 patients presenting defunctionalized bladders were prospectively evaluated with urodynamics. The studies were performed immediately before and six months after renal transplantation. Inclusion criteria were age >18 years-old, end-stage renal disease secondary to non-urological disease, renal substitutive therapy longer than 12 months, waiting for deceased donor organ. Exclusion criteria was: abnormal urinary tract ultrasound, voiding cystourethrography or urinalyses and 24 hours residual diuresis higher than 1000ml. Results: Complete recovery of bladder function was observed after return of diuresis, on the sixth month post transplantation, independently of the presence of bladder defunctionalization. Urodynamics parameters changes from baseline to six months were: first sensation of bladder filling: 88.8 to 168.7ml (p = 0.0005); first desire to void: 137.2 to 251.1ml (p <0.0001); maximum cystometric capacity: 221.2 to 428.7ml (p <0.0001); bladder compliance: 73.9 to 138.6 ml/cm H2O (p = 0.03) and maximum flow rate: 8.1 to 15.8 ml/s (p <0.0001). The Abrams-Griffths number in men reduced from 31.8 to 15.2 (p = 0.002). No significant chances were observed in detrusor pressure at maximum flow rate and post void residual volume. Patients with 24 hours diuresis volume lower than 200ml tended to have more significant abnormalities in urodynamics parameters before transplantation. Conclusions: A complete recovery of bladder function was observed in patients with end stage renal disease, without urological disease, six months after transplant, associated with recovery of urine output by the renal graft / Mestrado / Fisiopatologia Cirúrgica / Mestre em Ciências

Background The proliferation signal inhibitors (PSIs) sirolimus (SRL) and everolimus (ERL) are the potent immunosuppressive drugs using in organ transplantation and has been used successfully in renal transplant recipients (RTX) as well. PSIs are the key factors to overcome the allograft rejections after successful organ transplantation since the immune system starts to react against the graft. SRL and ERL prevents the action of immune system b inhibits the proliferation of T- and B-cells by inhibiting the intracellular signaling of interleukin-2. The presence of excess amount of serum proteins including albumin in the urine is considered as proteinuria, which reflects the loss of kidney function. The occurrence of proteinuria can be the result of abnormal glomerular filtration and/or impaired tubular endocytic function of renal proximal tubular epithelial cells (PTECs). Megalin and cubulin are two scavenger receptors present on epical surface of PTECs and involved in reabsorption of proteins after glomerular ultrafiltration process in the kidney. Proteinuria appears too high in renal transplanted patients during ongoing   treatment with PSIs. Aim Our study aimed to investigate and correlate the expression level of megalin and cubilin and albumin uptake in PTEC of renal transplanted patients before and after conversion to PSI. Methods To retrieve the maximal expression of our interest molecules in renal PTECs, we optimized antigen retrieval (AR) method and primary antibody dilution for each molecule separately. An optimization experiment was performed on 3 different normal patients renal biopsies were used. Later, human renal biopsy specimens originated from 4 different renal transplanted patients were used in this study. From all the 4 patients biopsy specimens were taken before and ongoing administration of PSIs (SRL, ERL). The expression of megalin, cubilin and albumin uptake in PTEC of renal transplant patients was determined by immunohistochemical staining. Results Based on the optimization experiments, we selected the AR method and primary antibody dilution for the expression of megalin, cubilin and albumin uptake. In 4 renal transplanted patients following administration of PSIs results in patients 1, 2, 3 expression of megalin, cubilin and albumin uptake during ongoing PSI treatment was not comparable or even more intense than before PSIs introduction. The expression of megalin, cubilin and albumin uptake was reduced in patient 4 during ongoing PSI treatment. Conclusion Our findings suggest that the renal transplant patient 4 developed proteinuria during PSI medication. The expression of megalin, cubilin and albumin uptake was markedly decreased during ongoing PSI treatment in patient 4. We concluded that there is a direct link between PSI medication and tubular dysfunction, which might cause proteinuria

La transplantation rénale reste le traitement de choix du stade terminal la maladie rénale chronique. Malgré la diminution très significative de l'incidence du rejet aigu à médiation cellulaire (ACR), la survie à long terme des greffons rénaux reste relativement stable probablement à cause de l'augmentation du rejet à médiation humorale. Dans cette thèse, nous avons exploré deux objectifs de l'analyse moléculaire au cours de la transplantation rénale dont les biomarqueurs font partie intégrante : la prédiction de l'épisode de rejet aigu avant même l'apparition des lésions histologiques et l'amélioration de nos connaissances sur la physiopathologie des mécanismes immunologiques afin de pouvoir adapter le mieux possible le traitement immunosuppresseur.Dans un premier travail clinique préliminaire à la recherche de biomarqueurs, nous avons analysé dans une cohorte rétrospective de 87 patients, les facteurs de risque indépendants de perte du greffon rénal après un épisode de rejet aigu à médiation humorale (AMR) C4d positif. L'analyse par régression de Cox a retrouvé deux deux facteurs de risque : le niveau initial de dégradation de la fonction du greffon rénal et la présence concomittante d'un rejet aigu à médiation cellulaire. Dans un deuxième travail, nous avons exploré la possibilité d'utiliser des biomarqueurs non invasifs plutôt que la biopsie du greffon rénal chez des patients avec dysfonction aigue du greffon, situation à risque de dysfonction chronqiue du greffon rénal. Nous avons mesuré le niveau d'expression urinaire de 26 ARN messagers préselectionnés chez 84 transplantés rénaux avec dysfonction aigue du greffon, 32 nécrose tubulaire aigue, 26 ACR et 26 AMR Puis par une analyse discriminante suivie d'une validation croisée, nous avons découvert et validé une combinaison linéaire de six ARNm CD3e, CD105, TLR4, CD14, le facteur B du complément et la vimentine différentiant efficacement le rejet aigu de la nécrose tubulaire aigue. Cette combinaison linéaire permet d'épargner un nombre significatif de biopsies du greffon non indispensables. Puis, par la même technique, nous avons découvert et validé une nouvelle combinaison linéaire d'ARNm CD3e, CD105, CD14, CD46, et l'ARNr 18S pouvant différentier efficacement l'ACR de l'AMR. A l'avenir ces signatures pourraient diminuer le recours à la réalisation d'une biopsie du greffon puis une aide au diagnostic précoce des épisodes de rejets aigus. Dans un troisième travail, nous avons analysé le phénotype lymphocytaire B de patients transplantés rénaux traités par anticalcineurines (CNI) (N=12) et belatacept (N=13), immunosuppresseur inhibiteur de la costimulation. Les patients traités par belatacept ont une meilleure survie à long terme que ceux traités par CNI. Chez les patients traités par belatacept, nous avons retrouvé un phénotype B particulier avec une augmentation significative des lymphocytes B et des lymphocytes B transitionnels CD19+ CD24hi CD38hi et CD19+ IgDhi CD38hi CD27 potentiellement régulateurs par rapport aux patients traités par CNI. Le niveau d'expression de l'ARNm de BAFF et de BAFF-R dans les PBMCs était significativement plus bas chez les patients traités par belatacept. Nos résultats pourraient expliquer en partie les meileurs résultats cliniques observés chez les patients traités par belatacept après transplantation rénale.En conclusion, au cours de cette thèse, nous avons évalué l'intérêt des biomarqueurs, dans deux domaines, la recherche de facteurs pronostiques et diagnostiques du rejet aigu à médiation humorale par l'analyse d'une cohorte clinique et du transcriptome urinaire d'une partie de cette cohorte et l'analyse des mécanismes physiopathologiques au cours de la tolérance induite par le belatacept. Nos résultats méritent d'être confirmés dans des cohortes indépendantes de patients avant leur utilisation en pratique clinique courante et l'évaluation de leur impact sur la survie des greffons rénaux. / Kidney transplantation remains the best treatment in advanced chronic kidney disease. Acute T-cell mediated rejection (ACR) decreased significantly but long-term kidney allograft survival did not increase significantly these last ten years. Antibody-mediated rejection is probably the main part of the problem. In this work, we explored two ways of the molecular analysis of kidney transplant, including biomarkers: prediction of rejection and study of the mechanisms of immunosuppressiv agents within kidney transplantation.The first one, a preliminary clinical work, identified in a retrospective cohort of 87 for-cause biopsies with C4d positive acute antibody-mediated rejection (AMR) independant risk factors for renal allograft failure after the AMR. The Cox regression analysis identified that concurrent ACR and estimated glomerular filtration rate are independent risk factors for allograft loss. The second one explored how noninvasive tests to differentiate the basis for acute dysfunction of the kidney allograft could replace invasive allograft biopsy. We measured absolute levels of 26 prespecified mRNAs in urine samples collected from kidney graft recipients at the time of for-cause biopsy for acute allograft dysfunction. We profiled 52 urine samples from 52 patients with biopsy specimens indicating acute rejection (26 ACR and 26 AMR) and 32 urine samples from 32 patients with acute tubular injury (ATI) without acute rejection. A stepwise quadratic discriminant analysis ofmRNA measures identified a linear combination ofmRNAs for CD3e, CD105, TLR4, CD14, complement factor B, and vimentin that distinguishes acute rejection from ATI; 10-fold cross-validation of the six-gene signature yielded an estimate of the area under the curve of 0.92 (95% CI, 0.86 to 0.98). In a decision analysis, the sixgene signature yielded the highest net benefit across a range of reasonable threshold probabilities for biopsy. Next, among patients diagnosed with acute rejection, a similar statistical approach identified a linear combination ofmRNAs for CD3e, CD105, CD14, CD46, and 18S rRNA that distinguishes ACR from AMR, with a cross-validated estimate of the area under the curve of 0.81 (95% CI, 0.68 to 0.93). Incorporation of these urinary cell mRNA signatures in clinical decisions may reduce the number of biopsies in patients with acute dysfunction of the kidney allograft. In the third one, we analyzed B cell phenotype in kidney transplant recipients treated with the costimulation blocker belatacept and compared them to recipients treated with calcineurin inhibitors (CNI). Phase III clinical studies have shown that patients kidney treated belatacept exhibited a better renal allograft function and lower donor-specific anti-HLA immunization when compared to recipients treated with CNI. Thirteen patients treated with belatacept and 12 with CNI were phenotyped. In belatacept group, the frequency and absolute number of transitional B cells as defined by both phenotypes: CD19+ CD24hi CD38hi and CD19+ IgDhi CD38hi CD27-, as well as naïve B cells were significantly higher compared with CNI group. B cell activating factor (BAFF) and BAFF receptor mRNA levels were significantly lower in belatacept group than in CNI group. These results show for the first time that belatacept influences B cell compartment by favoring the occurrence of transitional B cells with potential regulatory properties, as described in operational tolerant patients. This role may explain the lower alloimmunization rate observed in belatacept-treated patients.To conclude, we evaluated biomarkers analysis within two ways, acute antibody-mediated rejection prognosis and diagnosis with a clinical cohort and urinary transcriptomic analysis and mechanisms of action of belatacept induced tolerance. Our results need to be validated in an independent cohort before to be integrated in clinical decision and evaluation of their impact on long term graft survival.

Bien que le Tacrolimus soit un immunosuppresseur largement prescrit en transplantation rénale, ses effets néphrotoxiques limitent son utilisation. En effet, le Tacrolimus contribue au développement de lésions de fibrose interstitielle rénale et d’atrophie tubulaire à plus ou moins brève échéance. Parmi les mécanismes qui interviennent dans le processus de fibrogenèse, la transition épithélio-mésenchymateuse (TEM) a été évoquée. Dans ce processus, une cellule épithéliale polarisée perd l’expression de certains de ses marqueurs épithéliaux (E-cadhérine, cytokératine, &#946;-caténine membranaire...) au profit d’un phénotype mésenchymateux (expression de marqueurs mésenchymateux tels que vimentine ou translocation nucléaire de la &#946;-caténine, sécrétion de composants de la matrice extracellulaire). Ainsi, afin d’identifier des déterminants moléculaires de la néphrotoxicité induite par le Tacrolimus et d’évaluer la contribution du processus de TEM, plusieurs approches in vitro et in vivo ont été combinées.Tout d’abord, un modèle de culture primaire de cellules tubulaires proximales rénales (CTP), cibles privilégiées des xénobiotiques au niveau rénal a été développé à partir de pièces opératoires. Ce modèle a été caractérisé : analyse de la stabilité sur 5 passages, de l’expression de marqueurs épithéliaux proximaux et mésenchymateux, et de la résistance trans-épithéliale... De plus, la comparaison de la capacité métabolique des échantillons de tissu rénal sain à différents modèles cellulaires (HEK293, HK-2, CTP) nous a permis de montrer que les CTP est le modèle le plus pertinent. De plus, l’exposition de cellules rénales au Tacrolimus induit une modification du phénotype des cellules.De plus, le développement d’un modèle murin de néphrotoxicité induite par le Tacrolimus a été réalisé (exposition durant 28 jours à une dose de 1 mg/kg/j de Tacrolimus par implantation sous-cutanée de pompes Alzet® ou par injection intra-péritonéale). Les données histologiques et d’expression génique montrent que les reins de souris traitées par Tacrolimus présentent des zones localisées d’expression des marqueurs mésenchymateux (vimentine) et de fibrose (collagène, &#945;-SMA, miR-21). Par ailleurs, la variabilité interindividuelle des effets néphrotoxiques du Tacrolimus étant potentiellement associée à la présence de polymorphismes génétiques (SNP), les ADN de patients transplantés rénaux et de leur greffon ont été génotypés pour des SNP (i) affectant les CYP3A5 et ABCB1, intervenant dans la prise en charge du Tacrolimus, (ii) affectant la cavéoline-1, impliquée dans le processus de fibrose. Nos résultats montrent que deux SNP affectant le donneur (CYP3A5 6986A>G et ABCB1 3435C>T) sont significativement associés à une plus faible expression des marqueurs de TEM (expression de novo de la vimentine et translocation nucléaire de la &#946;-caténine) et à un nombre moins important de lésions de fibrose rénale sur les biopsies de greffons à 3 mois post-greffe. Enfin, les patients porteurs d’un greffon de génotype CAV1 rs4730751AA ont une perte de fonction rénale plus rapide. Ces patients semblent développer plus fréquemment des lésions de fibrose. Dans le cadre de la transplantation rénale, ces résultats suggèrent que certains SNP du donneur influencent la néphrotoxicité du Tacrolimus et que son métabolisme in situ est un élément clé dans la compréhension de la fibrogenèse du greffon.Au total, les résultats obtenus nous ont permis d’identifier des facteurs individuels de vulnérabilité à la toxicité du Tacrolimus. De telles données, utilisées comme outil prédictif d’une néphrotoxicité plus ou moins importante, aideraient à un meilleur choix de traitement immunosuppresseur. A terme, sur le plan médico-économique, notre étude pourrait permettre d’améliorer la prise en charge de la néphrotoxicité des immunosuppresseurs, et ainsi réduire les coûts de traitement liés aux pertes de greffons induites par la toxicité du Tacrolimus. / Although widely prescribed in kidney transplantation, Tacrolimus use is limited by its nephrotoxic effects. Indeed, Tacrolimus contributes to the development of renal interstitial fibrosis lesions and tubular atrophy with a large variability between patients. Among the mechanisms involved in fibrogenesis, the epithelial-mesenchymal transition (EMT) has been proposed. EMT is a dynamic process by which a polarized epithelial cell loses its epithelial markers (E-cadherin, cytokeratin, membrane &#946;-catenin...) and acquires a mesenchymal phenotype (de novo expression of vimentin or nuclear translocation of &#946;-catenin, secretion of extracellular matrix components). Thus, to identify molecular determinants of Tacrolimus-induced nephrotoxicity and to evaluate the contribution of EMT, several in vitro and in vivo approaches were combined.First, a model of primary culture of renal proximal tubular cells (PT cells), the main target of xenobiotics in kidney, has been developed and characterized: phenotypic stability, functional properties, expression of proximal and mesenchymal markers and transepithelial resistance. In addition, the comparison of the metabolic capacity of the healthy renal tissue samples to different cell models (HEK293, HK-2 CTP) has revealed that PT cells is the most appropriate model. Furthermore, renal cells exposure to Tacrolimus induced a modification of the cell phenotype.Moreover, the development of a murine model of Tacrolimus-induced nephrotoxicity has been performed (28 days-exposure at 1 mg/kg/day by subcutaneous implantation of Alzet® pumps or by intra-peritoneal injection). Histological and gene expression data indicated that kidney of Tacrolimus-treated mice exhibited localized expression of mesenchymal markers (vimentin) and fibrosis areas (collagen, &#945;-SMA, miR-21).Furthermore, as the interindividual variability of Tacrolimus nephrotoxic effects is potentially associated with genetic polymorphisms (SNPs), renal transplant recipients and their corresponding graft were genotyped for (i) CYP3A5 and ABCB1 SNPs, involved in Tacrolimus cellular processing, (ii) caveolin-1 SNP, involved in fibrosis. Our results showed that two SNPs affecting the donor (CYP3A5 6986A> G and ABCB1 3435C> T) were significantly associated with a lower expression of EMT markers (vimentine de novo expression and nuclear translocation of &#946;-catenin) together with less fibrosis lesions evaluated on renal graft biopsies performed at 3 months post-transplant. Finally, patients with a CAV1 rs4730751AA graft displayed a more severe renal function decrease. These patients also developed more frequently fibrotic lesions. In the context of renal transplantation, these results suggest that some donor SNPs modulate Tacrolimus-induced nephrotoxicity and that its in situ metabolism is a key element in the graft fibrogenesis understanding.Overall, these data allowed us to identify some molecular determinants of Tacrolimus-induced nephrotoxicity. Early identification of patients at high risk of Tacrolimus renal toxicity represents one of the most important and future challenges in kidney transplantation to tailor treatment before the development of irreversible lesions. Although preliminary, our data suggest that the genetic make-up of donors as well as the early detection of nephrotoxicity markers such as mesenchymal markers, may improve to the medical management of renal transplant patients.

Contexte : L'histologie rénale est une pierre angulaire de la prise en charge néphrologique mais plusieurs facteurs en limitent les capacités nécessitant le développement de nouvelles techniques. La spectroscopie vibrationnelle (SV), Raman (SR) et infrarouge (FTIR), apporte des informations moléculaires et structurelles de manière reproductible sans préparation préalable des échantillons tissulaires la rendant apte à lever ces limitations. Objectif : L'objectif de ce travail est de démontrer l'intérêt de la SV et son potentiel à apporter des informations à partir des biopsies rénales, actuellement indisponibles via les techniques habituelles. Design : Nous avons recherché dans le rein : 1) Des molécules exogènes : Hydroxyethyl amidon (HEA) 2) Des molécules endogènes : les produits de glycation avancée (AGEs) 3) La quantification de structures pathologiques: fibrose et inflammation. Résultats : 1) L'HEA a été détectée par SR dans des biopsies rénales de patients exposés à cette molécule exogène affirmant son accumulation rénale. La quantification de l'HEA par SR sur des biopsies de greffons rénaux a permis d'associer son accumulation à une bonne qualité du greffon estimée par un score de risque du donneur (KDRI) et la fonction rénale à 3 mois de la greffe. 2) 4 AGEs ont été cartographiés et quantifiés dans des glomérules diabétiques et normaux par SR. Ils étaient augmentés dans les glomérules diabétiques vs normaux. Une faible proportion des AGEs a été retrouvée colocalisée au collagène dans les glomérules diabétiques et non dans les glomérules normaux. 3) La fibrose interstitielle et l'inflammation ont été automatiquement quantifiée par FTIR sur 166 biopsies de greffons rénaux de manière reproductible et robuste. La pertinence clinique de cette technique a été prouvée par une bonne corrélation avec la fonction rénale. Conclusion : La SV possède un fort potentiel en néphrologie avec de multiples applications en recherche comme en pratique clinique. / Background: Renal biopsy is a main feature of diagnosis and prognosis in nephrology but it still have some limitation which need further techniques to be more reliable. Vibrational spectroscopy (VS) including Raman spectroscopy (RS) and Fourier-transformed infrared spectroscopy (FTIR) bring out some molecular and structural data from tissue analysis. Objective: We aimed to prove VS is able to provide histologic data actually unattainable by classical techniques. Design: We searched in renal biopsies: 1) Exogenous molecules: Hydroxyethyl starch (HES) 2) Endogenous molecules: Advanced glycation end-product (AGEs) 3) Reproducible quantification of interstitial fibrosis and inflammation in renal grafts. Results: 1) We reported an accumulation of HES by RS in renal biopsies from patients exposed to this molecule. Moreover, accumulation of HES in renal graft biopsies exposed to HES was dependent on good quality of graft defined by kidney donor risk index and renal function at 3 months. 2) 4 AGEs were mapped and quantified by RS in diabetic and normal glomeruli. Levels of each AGE were higher diabetic glomeruli vs controls. In diabetic glomeruli, some AGEs were collocated with collagen that was not found in normal glomeruli. 3) Interstitial fibrosis (IF) and inflammation were quantified in 166 renal graft biopsies by an automated FTIR technique. We assessed the robustness of this technique for discrimination of fibrosis and inflammation. We proved the clinical relevance of this technique by showing a good correlation of IF with renal graft function. Conclusion: Vibrational spectroscopy is a promising technique for nephrology both in basic research and in clinical practice.

Background: In the United States, increasing ethnic diversity has been apparent. However, the epidemiology and trends of BKV genotypes remain unclear. This meta-analysis was conducted with the aim to assess the prevalence of BKV genotypes among kidney transplant (KTx) recipients in the United States. Methods: A comprehensive literature review was conducted through October 2018 utilizing MEDLINE, Embase, and Cochrane Database to identify studies that reported the prevalence of BKV subtypes and/or subgroups in KTx recipients in the United States. Pooled prevalence rates were combined using random effects, generic inverse variance method. The protocol for this study is registered with PROSPERO (no. CRD42019134582). Results: A total of eight observational studies with a total of 193 samples (urine, blood, and kidney tissues) from 188 BKV-infected KTX recipients were enrolled. Overall, the pooled estimated prevalence rates of BKV subtypes were 72.2% (95% confidence of interval [CI]: 62.7-80.0%) for subtype I, 6.8% (95% CI: 2.5-16.9%) for subtype II, 8.3% (95% CI: 4.4-15.1%) for subtype III, and 16.1% (95% CI: 10.4-24.2%) for subtype IV, respectively. While metaregression analysis demonstrated a significant positive correlation between year of study and the prevalence of BKV subtype I (slopes = +0.1023, P =.01), there were no significant correlations between year of study and percentages of BKV subtype II-IV (P >.05). Among KTx recipients with BKV subtype I, the pooled estimated percentages of BKV subgroups were 22.4% (95% CI: 13.7-34.5%) for subgroup Ia, 30.6% (95% CI: 17.7-47.5%) for subgroup Ib1, 47.7% (95% CI: 35.8-59.9%) for subgroup Ib2, and 4.1% (95% CI:1.2-13.3%) for subgroup Ic, respectively. Conclusion: BKV subtype I is the most prevalent subtype among KTx recipients in the United States and its prevalence seems to increasing overtime. Subgroup Ib2 is the most common subgroup among BKV subtype I.

BACKGROUND: The adverse renal effects of proton pump inhibitors (PPIs) are increasingly recognized in both the general population and patients with chronic kidney disease. Several pharmacokinetic studies have also raised concerns regarding the interaction between PPIs and immunosuppressive drugs in transplant patients. Whether the adverse effects of PPIs have a clinical significance in kidney transplant recipients remains unclear. We performed this meta-analysis to assess the risk of adverse effects in kidney transplant recipients on PPI compared with those without PPI exposure. AIM: To investigate the risk of acute rejection, graft loss, hypomagnesemia, renal dysfunction, and overall mortality in kidney transplant recipients on PPI compared with those without PPI exposure. METHODS: A systematic review was conducted in MEDLINE, EMBASE, and Cochrane databases from inception through October 2018 to identify studies that evaluated the adverse effects of PPIs in kidney transplant recipients, including biopsy-proven acute rejection, graft loss, hypomagnesemia, renal function, and overall mortality. Effect estimates from the individual studies were extracted and combined using random-effect, generic inverse variance method of DerSimonian and Laird. The protocol for this meta-analysis is registered with PROSPERO, No. CRD42018115676. RESULTS: Fourteen observational studies with 6786 kidney transplant recipients were enrolled. No significant association was found between PPI exposure and the risk of biopsy-proven acute rejection at ≥ 1 year [pooled odds ratio (OR), 1.25; 95% confidence interval (CI), 0.82-1.91, = 55%], graft loss at 1 year (pooled OR = 1.30, 95%CI: 0.75-2.24, = 0%) or 1-year mortality (pooled OR = 1.53, 95%CI: 0.90-2.58, = 34%). However, PPI exposure was significantly associated with hypomagnesemia (pooled OR = 1.56, 95%CI: 1.19-2.05, = 27%). Funnel plots and Egger regression asymmetry test were performed and showed no publication bias. CONCLUSION: PPI use was not associated with significant risks of higher acute rejection, graft loss, or 1-year mortality. However, the risk of hypomagnesemia was significantly increased with PPI use. Thus, future studies are needed to assess the impact of PPIs on long-term outcomes.

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