RESUMO
BACKGROUND: Regulatory T cell (Treg) therapy is a promising approach to amelioration of allograft rejection and promotion of organ transplant tolerance. However, the fate of infused Treg, and how this relates to their therapeutic efficacy using different immunosuppressive regimens is poorly understood. Our aim was to analyze the tissue distribution, persistence, replicative activity and phenotypic stability of autologous, donor antigen alloreactive Treg (darTreg) in anti-thymocyte globulin (ATG)-lymphodepleted, heart-allografted cynomolgus monkeys. METHODS: darTreg were expanded ex vivo from flow-sorted, circulating Treg using activated donor B cells and infused posttransplant into recipients of major histocompatibility complex-mismatched heart allografts. Fluorochrome-labeled darTreg were identified and characterized in peripheral blood, lymphoid, and nonlymphoid tissues and the graft by flow cytometric analysis. RESULTS: darTreg selectively suppressed autologous T cell responses to donor antigens in vitro. However, following their adoptive transfer after transplantation, graft survival was not prolonged. Early (within 2 wk posttransplant; under ATG, tacrolimus, and anti-IL-6R) or delayed (6-8 wk posttransplant; under rapamycin) darTreg infusion resulted in a rapid decline in transferred darTreg in peripheral blood. Following their early or delayed infusion, labeled cells were evident in lymphoid and nonlymphoid organs and the graft at low percentages (<4% CD4+ T cells). Notably, infused darTreg showed reduced expression of immunoregulatory molecules (Foxp3 and CTLA4), Helios, the proliferative marker Ki67 and antiapoptotic Bcl2, compared with preinfusion darTreg and endogenous CD4+CD25hi Treg. CONCLUSIONS: Lack of therapeutic efficacy of infused darTreg in lymphodepleted heart graft recipients appears to reflect loss of a regulatory signature and proliferative and survival capacity shortly after infusion.
Assuntos
Transferência Adotiva , Soro Antilinfocitário/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Proliferação de Células , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Transplante de Coração , Ativação Linfocitária , Depleção Linfocítica , Linfócitos T Reguladores/transplante , Animais , Células Cultivadas , Modelos Animais de Doenças , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/metabolismo , Transplante de Coração/efeitos adversos , Macaca fascicularis , Masculino , Fenótipo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Fatores de TempoRESUMO
Liver interstitial dendritic cells (DCs) have been implicated in the control of ischemia-reperfusion injury (IRI) and host immune responses following liver transplantation. Mechanisms underlying these regulatory functions of hepatic DCs remain unclear. We have shown recently that the transmembrane immunoadaptor DNAX-activating protein of 12 kDa (DAP12) negatively regulates mouse liver DC maturation and proinflammatory and immune stimulatory functions. Here, we used PCR analysis and flow cytometry to characterize expression of DAP12 and its associated triggering receptor, triggering receptor expressed on myeloid cells 2 (TREM2), by mouse and human liver DCs and other immune cells compared with DCs in other tissues. We also examined the roles of DAP12 and TREM2 and their expression by liver DCs in the regulation of liver IRI. Injury was induced in DAP12-/- , TREM2-/- , or wild-type (WT) mice by 1 hour of 70% clamping and quantified following 6 hours of reperfusion. Both DAP12 and TREM2 were coexpressed at comparatively high levels by liver DCs. Mouse liver DCs lacking DAP12 or TREM2 displayed enhanced levels of nuclear factor κB and costimulatory molecule expression. Unlike normal WT liver DCs, DAP12-/- liver DC failed to inhibit proliferative responses of activated T cells. In vivo, DAP12-/- and TREM2-/- mice exhibited enhanced IRI accompanied by augmented liver DC activation. Elevated alanine aminotransferase levels and tissue injury were markedly reduced by infusion of WT but not DAP12-/- DC. Conclusion: Our data reveal a close association between DAP12 and TREM2 expression by liver DC and suggest that, by negatively regulating liver DC stimulatory function, DAP12 promotes their control of hepatic inflammatory responses; the DAP12/TREM2 signaling complex may represent a therapeutic target for control of acute liver injury/liver inflammatory disorders.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Fígado/irrigação sanguínea , Glicoproteínas de Membrana/fisiologia , Proteínas de Membrana/fisiologia , Receptores Imunológicos/fisiologia , Traumatismo por Reperfusão/etiologia , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Animais , Células Dendríticas/metabolismo , Humanos , Fígado/citologia , Masculino , Glicoproteínas de Membrana/biossíntese , Proteínas de Membrana/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Receptores Imunológicos/biossínteseRESUMO
Although a key role of cross-dressing has been established in immunity to viral infection and more recently in the instigation of transplant rejection, its role in tolerance is unclear. We investigated the role of intragraft dendritic cells (DCs) and cross-dressing in mouse major histocompatibility complex (MHC)-mismatched liver transplant tolerance that occurs without therapeutic immunosuppression. Although donor interstitial DCs diminished rapidly after transplantation, they were replaced in the liver by host DCs that peaked on postoperative day (POD) 7 and persisted indefinitely. Approximately 60% of these recipient DCs displayed donor MHC class I, indicating cross-dressing. By contrast, only a very minor fraction (0%-2%) of cross-dressed DCs (CD-DCs) was evident in the spleen. CD-DCs sorted from liver grafts expressed much higher levels of T cell inhibitory programed death ligand 1 (PD-L1) and high levels of interleukin-10 compared with non-CD-DCs (nCD-DCs) isolated from the graft. Concomitantly, high incidences of programed death protein 1 (PD-1)hi T cell immunoglobulin and mucin domain containing 3 (TIM-3)+ exhausted graft-infiltrating CD8+ T cells were observed. Unlike nCD-DCs, the CD-DCs failed to stimulate proliferation of allogeneic T cells but markedly suppressed antidonor host T cell proliferation. CD-DCs were much less evident in allografts from DNAX-activating protein of 12 kDa (DAP12)-/- donors that were rejected acutely. CONCLUSION: These findings suggest that graft-infiltrating PD-L1hi CD-DCs may play a key role in the regulation of alloimmunity and in the induction of liver transplant tolerance. (Hepatology 2018;67:1499-1515).
Assuntos
Células Dendríticas/imunologia , Sobrevivência de Enxerto/imunologia , Fígado/imunologia , Tolerância ao Transplante/imunologia , Animais , Citometria de Fluxo , Microscopia Intravital , Transplante de Fígado/efeitos adversos , Complexo Principal de Histocompatibilidade/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transplante HomólogoRESUMO
BACKGROUND: Auxiliary partial liver transplantation (APLT) in humans is a therapeutic modality used especially to treat liver failure in children or congenital metabolic disease. Animal models of APLT have helped to explore therapeutic options. Though many groups have suggested improvements, standardizing the surgical procedure has been challenging. Additionally, the question of whether graft livers are reconstituted by recipient-derived cells after transplantation has been controversial. The aim of this study was to improve experimental APLT in rats and to assess cell recruitment in the liver grafts. METHODS: To inhibit recipient liver regeneration and to promote graft regeneration, we treated recipients with retrorsine and added arterial anastomosis. Using green fluorescence protein transgenic rats as recipients, we examined liver resident cell recruitment within graft livers by immunofluorescence costaining. RESULTS: In the improved APLT model, we achieved well-regenerated grafts that could maintain regeneration for at least 4 weeks. Regarding the cell recruitment, there was no evidence of recipient-derived hepatocyte, cholangiocyte, or hepatic stellate cell recruitment into the graft. Macrophages/monocytes, however, were consistently recruited into the graft and increased over time, which might be related to inflammatory responses. Very few endothelial cells showed colocalization of markers. CONCLUSIONS: We have successfully established an improved rat APLT model with arterial anastomosis as a standard technique. Using this model, we have characterized cell recruitment into the regenerating grafts.
Assuntos
Movimento Celular , Proliferação de Células , Regeneração Hepática , Transplante de Fígado/métodos , Fígado/cirurgia , Animais , Linhagem da Célula , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Fígado/fisiopatologia , Regeneração Hepática/efeitos dos fármacos , Masculino , Modelos Animais , Alcaloides de Pirrolizidina/farmacologia , Ratos Endogâmicos F344 , Ratos Sprague-Dawley , Ratos Transgênicos , Fatores de TempoRESUMO
BACKGROUND: Delayed graft function (DGF) is an early complication of kidney transplant (KT) and it is related to a higher incidence of acute rejection (AR) and lower graft survival. The incidence of DGF ranges from 2 to 29% in different series. Several risk factors for DGF have been described, including inotropic use in the deceased donor, long cold ischemia time, cardiovascular brain death, age > 55 years, hypovolemia, previous transplant, preformed antibodies and OKT3 use. MATERIAL AND METHODS: This study is a retrospective cohort of the kidney transplant recipients (KTR) of deceased donors from 1990 to 2009, at the INCMNSZ. We analyzed the incidence of DGF, risk factors associated to its development, and patient and graft outcome. To compare the groups, we used chi2 test or Student's t test for categorical and numeric variables, respectively. Patient and graft survival were calculated using Kaplan-Meier method; a p value < 0.05 was considered statistically significant. RESULTS: Data from 105 KTR were analyzed. DGF occurred in 21%, AR in 27%, graft loss in 15.2%. The only risk factor associated to DGF was brain death due to vascular disease (p = 0.028). CONCLUSIONS: Brain death due to vascular disease was the only risk factor associated to DGF. A non-significant higher incidence of AR was observed in patients with DGF. Survival was significantly lower in patients who developed DGF compared to those without DGF, and it was not related to renal function.
Assuntos
Função Retardada do Enxerto/epidemiologia , Sobrevivência de Enxerto , Transplante de Rim/mortalidade , Adulto , Cadáver , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos Retrospectivos , Fatores de Risco , Taxa de SobrevidaRESUMO
Fabry-Anderson disease is a lysosomal storage disease caused by deficiency of the enzyme alpha-galactosidase. This enzymatic defect results in the accumulation of glycosphingolipid into different lines cells. Usually the deficiency is complete, resulting in a multisystem disorder, with injury in different organs, predominantly heart, kidney and nervous system. However, in some patients the enzymatic deficit is partial and causes diverse clinical variants of the disease (renal or cardiac variety), this cause a difficult diagnostic and the absence of real epidemiology data. This review is about the epidemiology, the metabolic defect of this disease, it's molecular and genetics bases, the different forms of clinical presentation and the enzyme replacement therapy.
Assuntos
Doença de Fabry , Cromossomos Humanos X/genética , Estudos de Coortes , Endotélio Vascular/enzimologia , Terapia de Reposição de Enzimas , Doença de Fabry/diagnóstico , Doença de Fabry/tratamento farmacológico , Doença de Fabry/enzimologia , Doença de Fabry/epidemiologia , Doença de Fabry/genética , Humanos , Rim/enzimologia , Lisossomos/enzimologia , Masculino , Miocárdio/enzimologia , Especificidade de Órgãos , Fenótipo , Ensaios Clínicos Controlados Aleatórios como Assunto , alfa-Galactosidase/análise , alfa-Galactosidase/biossíntese , alfa-Galactosidase/genética , alfa-Galactosidase/uso terapêutico , alfa-N-Acetilgalactosaminidase/uso terapêuticoRESUMO
INTRODUCTION: The recipients of HLA-identical live-donors grafts (RKT 2HP) have a low immunologic risk, and it is common to use immunosuppressive regimen with two medicaments excluding the calcineurin inhibitor. This study compares the long term outcomes of the double immunosuppressive therapy versus the triple therapy in RKT 2HP. MATERIALS AND METHODS: This study is a retrolective cohort. The patients were divided in two groups: (1) RKT 2HP who receive double immunosupresive therapy and (2) RKT 2HP with triple immunosupresive therapy. The outcomes evaluated were: renal function, acute rejection rate, lost of renal allograft, death rate, infections and hospitalization, change in the immunosupresive therapy and its causes. RESULTS: We analyzed 85 kidney transplant recipients who share two haplotypes, 60 in the group 1 and 25 in the group 2. The median of time of follow-up in the group 1 was 138 months (min 23 and max 302) and 55 months (min 12 and max 106) in the group 2. There were four cellular acute rejection and nine allograft lost in patients of the group 1. There wasn't any significant difference between the allograft outcome and the renal function at 60 months of follow out between the groups. 23 patients had change in the immunosuppressive therapy, 12 (53%) in the group 1 and 11 (47%) in the group 2. The major cause of change of therapy in the group 1 was leucopenia by azatioprin (five patients); and in the group 2 was nephrotoxicity for calcineurin inhibitor (six patients). DISCUSSION: Despite the evident nephrotoxicity, the use of calcineurin inhibitor is useful even in patients with low immunologic risk. According to the time of follow-up between the groups, even when the allograft survival was superior in group 2, the difference wasn't significative, it might be because the lower number of patients in group 1.