RESUMEN
Ever since its first application in clinical medicine, scientists have been urged to induce tolerance towards foreign allogeneic transplants and thus avoid rejection by the recipient's immune system. This would circumvent chronic use of immunosuppressive drugs (IS) and thus avoid development of IS-induced side effects, which are contributing to the still unsatisfactory long-term graft and patient survival after solid organ transplantation. Although manifold strategies of tolerance induction have been described in preclinical models, only three therapeutic approaches have been utilized successfully in a still small number of patients. These approaches are based on (i) IS withdrawal in spontaneous operational tolerant (SOT) patients, (ii) induction of a mixed chimerism and (iii) adoptive transfer of regulatory cells. Results of clinical trials utilizing these approaches show that tolerance induction does not work in all patients. Thus, there is a need for reliable biomarkers, which can be used for patient selection and post-therapeutic immune monitoring of safety, success and failure. In this review, we summarize recent achievements in the identification and validation of such immunological assays and biomarkers, focusing mainly on kidney and liver transplantation. From the published findings so far, it has become clear that indicative biomarkers may vary between different therapeutic approaches applied and organs transplanted. Also, patient numbers studied so far are very small. This is the main reason why nearly all described parameters lack validation and reproducibility testing in large clinical trials, and are therefore not yet suitable for clinical practice.
Asunto(s)
Supervivencia de Injerto , Inmunosupresores/uso terapéutico , Trasplante de Hígado , Monitorización Inmunológica/métodos , Tolerancia al Trasplante , Animales , Biomarcadores , Humanos , Inmunosupresores/efectos adversos , Trasplante HomólogoRESUMEN
Abdominal wall transplantation (AWTX) has revolutionized difficult abdominal closure after intestinal transplantation (ITX). More important, the skin of the transplanted abdominal wall (AW) may serve as an immunological tool for differential diagnosis of bowel dysfunction after transplant. Between August 2008 and October 2014, 29 small bowel transplantations were performed in 28 patients (16 male, 12 female; aged 41 ± 13 years). Two groups were identified: the solid organ transplant (SOT) group (n = 15; 12 ITX and 3 modified multivisceral transplantation [MMVTX]) and the SOT-AWTX group (n = 14; 12 ITX and 2 MMVTX), with the latter including one ITX-AWTX retransplantation. Two doses of alemtuzumab were used for induction (30 mg, 6 and 24 h after reperfusion), and tacrolimus (trough levels 8-12 ng/mL) was used for maintenance immunosuppression. Patient survival was similar in both groups (67% vs. 61%); however, the SOT-AWTX group showed faster posttransplant recovery, better intestinal graft survival (79% vs. 60%), a lower intestinal rejection rate (7% vs. 27%) and a lower rate of misdiagnoses in which viral infection was mistaken and treated as rejection (14% vs. 33%). The skin component of the AW may serve as an immune modulator and sentinel marker for immunological activity in the host. This can be a vital tool for timely prevention of intestinal graft rejection and, more important, avoidance of overimmunosuppression in cases of bowel dysfunction not related to graft rejection.
Asunto(s)
Pared Abdominal/cirugía , Rechazo de Injerto/diagnóstico , Intestinos/trasplante , Complicaciones Posoperatorias , Síndrome del Intestino Corto/cirugía , Enfermedades de la Piel/patología , Adulto , Femenino , Rechazo de Injerto/etiología , Supervivencia de Injerto , Humanos , Masculino , Estudios Prospectivos , Síndrome del Intestino Corto/complicaciones , Enfermedades de la Piel/etiología , Resultado del TratamientoRESUMEN
Acute cellular rejection occurs frequently during the first few weeks following liver transplantation. During this period, its molecular phenotype is confounded by peri- and postoperative proinflammatory events. To unambiguously define the molecular profile associated with rejection, we collected sequential biological specimens from 55 patients at least 3 years after liver transplantation who developed rejection during trials of intentional immunosuppression withdrawal. We analyzed liver tissue and blood samples obtained before initiation of drug withdrawal and at rejection, alongside blood samples collected during the weaning process. Gene expression profiling was conducted using whole-genome microarrays and real-time polymerase chain reaction. Rejection resulted in distinct blood and liver tissue transcriptional changes in patients who were either positive or negative for hepatitis C virus (HCV). Gene expression changes were mostly independent from pharmacological immunosuppression, and their magnitude correlated with severity of histological damage. Differential expression of a subset of genes overlapped across all conditions. These were used to define a blood predictive model that accurately identified rejection in HCV-negative, but not HCV-positive, patients. Changes were detectable 1-2 mo before rejection was diagnosed. Our results provide insight into the molecular processes underlying acute cellular rejection in liver transplantation and help clarify the potential utility and limitations of transcriptional biomarkers in this setting.
Asunto(s)
Biomarcadores/metabolismo , Perfilación de la Expresión Génica , Rechazo de Injerto/diagnóstico , Tolerancia Inmunológica/genética , Trasplante de Hígado , Complicaciones Posoperatorias , Privación de Tratamiento , Femenino , Estudios de Seguimiento , Regulación de la Expresión Génica , Rechazo de Injerto/etiología , Rechazo de Injerto/metabolismo , Supervivencia de Injerto , Humanos , Terapia de Inmunosupresión , Inmunosupresores/uso terapéutico , Hepatopatías/cirugía , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Adoptive immunotherapy with regulatory T cells (Treg) is a new option to promote immune tolerance following solid organ transplantation (SOT). However, Treg from elderly patients awaiting transplantation are dominated by the CD45RA(-) CD62L(+) central memory type Treg subset (TregCM), and the yield of well-characterized and stable naïve Treg (TregN) is low. It is, therefore, important to determine whether these TregCM are derived from the thymus and express high stability, suppressive capacity and a broad antigen repertoire like TregN. In this study, we showed that TregCM use a different T cell receptor (TCR) repertoire from conventional T cells (Tconv), using next-generation sequencing of all 24 Vß families, with an average depth of 534 677 sequences. This showed almost no contamination with induced Treg. Furthermore, TregCM showed enhanced suppressive activity on Tconv at early checkpoints of immune activation controlling activation markers expression and cytokine secretion, but comparable inhibition of proliferation. Following in vitro expansion under mTOR inhibition, TregCM expanded equally as well as TregN without losing their function. Despite relatively limited TCR repertoire, TregCM also showed specific alloresponse, although slightly reduced compared to TregN. These results support the therapeutic usefulness of manufacturing Treg products from CD45RA(-) CD62L(+) Treg-enriched starting material to be applied for adoptive Treg therapy.
Asunto(s)
Linfocitos T Reguladores/inmunología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Biomarcadores/metabolismo , Citocinas/metabolismo , Citometría de Flujo , Factores de Transcripción Forkhead/metabolismo , Voluntarios Sanos , Humanos , Trasplante de Riñón , Antígenos Comunes de Leucocito/metabolismo , Persona de Mediana Edad , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T Reguladores/metabolismo , Timo/citología , Timo/inmunologíaRESUMEN
Malignancy is an important cause of death in transplant recipients. Cutaneous squamous cell carcinoma (cSCC) causes significant morbidity and mortality as 30% of transplant recipients will develop cSCC within 10 years of transplantation. Previously we have shown that high numbers of regulatory T cells (Tregs) are associated with the development of cSCC in kidney transplant recipients (KTRs). Demethylation analysis of the Treg-specific demethylated region (TSDR) provides a more accurate association with cSCC risk after transplantation. Age, gender and duration of immunosuppression matched KTRs with (n=32) and without (n=27) cSCC, were re-analyzed for putative clinical and immunological markers of cancer risk. The proportion of FOXP3+ CD4+ cells was higher in the population with a previous SCC. Major T cell subsets remained stable over time; although B cell, CD8 and CD4 subpopulations demonstrated age-related changes. TSDR methylation analysis allowed clarification of Treg numbers, enhancing the association of high Treg levels in KTRs with cSCC compared to the cSCC-free cohort. These data validate and expand on previous findings in long-term KTRs, and show that immune markers remain stable over time. TSDR demethylation analysis provides a more accurate biomarker of cancer posttransplantation.
Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma de Células Escamosas/sangre , Metilación de ADN , Trasplante/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunosupresores/administración & dosificación , Masculino , Persona de Mediana EdadRESUMEN
Primary T cell activation and effector cell differentiation is required for rejection of allogeneic grafts in naïve recipients. It has become evident, that mitochondria play an important role for T cell activation. Expression of several mitochondrial proteins such as TCAIM (T cell activation inhibitor, mitochondrial) is down-regulated upon T cell receptor triggering. Here we report that TCAIM inhibited spontaneous development of memory and effector T cells. CD4(+) T cells from Tcaim knock-in (KI) mice showed reduced activation, cytokine secretion and proliferation in vitro. Tcaim KI T cells tolerated allogeneic skin grafts upon transfer into Rag-1 KO mice. CD4(+) and CD8(+) T cells from these mice did not infiltrate skin grafts and kept a naïve or central memory phenotype, respectively. They were unable to acquire effector phenotype and functions. TCAIM altered T cell activation-induced mitochondrial distribution and reduced mitochondrial reactive oxygen species (mROS) production. Thus, TCAIM controls T cell activation and promotes tolerance induction probably by regulating TCR-mediated mitochondrial distribution and mROS production.
Asunto(s)
Activación de Linfocitos/inmunología , Mitocondrias/inmunología , Proteínas Mitocondriales/fisiología , Trasplante de Piel , Linfocitos T Reguladores/inmunología , Linfocitos T/inmunología , Tolerancia al Trasplante/inmunología , Animales , Diferenciación Celular , Células Cultivadas , Citocinas/metabolismo , Citometría de Flujo , Proteínas de Homeodominio/fisiología , Memoria Inmunológica/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Linfocitos T/metabolismo , Trasplante HomólogoRESUMEN
To ensure safety tolerance induction protocols are accompanied by conventional immunosuppressive drugs (IS). But IS such as calcineurin inhibitors (CNI), for example, cyclosporin A (CsA), can interfere with tolerance induction. We investigated the effect of an additional transient CsA treatment on anti-CD4mAb-induced tolerance induction upon rat kidney transplantation. Additional CsA treatment induced deteriorated graft function, resulting in chronic rejection characterized by glomerulosclerosis, interstitial fibrosis, tubular atrophy and vascular changes. Microarray analysis revealed enhanced intragraft expression of the B cell attracting chemokine CXCL13 early during CsA treatment. Increase in CXCL13 expression is accompanied by enhanced B cell infiltration with local and systemic IgG production and C3d deposition as early as 5 days upon CsA withdrawal. Adding different CNIs to cultures of primary mesangial cells isolated from glomeruli resulted in a concentration-dependent increase in CXCL13 transcription. CsA in synergy with TNF-α can enhance the B cell attracting and activating potential of mesangial cells. Transient B cell depletion or transfer of splenocytes from tolerant recipients 3 weeks after transplantation could rescue tolerance induction and did inhibit intragraft B cell accumulation, alloantibody production and ameliorate chronic rejection.
Asunto(s)
Anticuerpos Monoclonales/farmacología , Linfocitos T CD4-Positivos/inmunología , Inhibidores de la Calcineurina , Tolerancia Inmunológica/inmunología , Inmunosupresores/farmacología , Trasplante de Riñón , Animales , Linfocitos B/inmunología , Calcineurina/farmacología , Quimiocina CXCL13/biosíntesis , Ciclosporina/farmacología , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Humanos , Tolerancia Inmunológica/efectos de los fármacos , Riñón/metabolismo , Activación de Linfocitos , Masculino , Ratas , Ratas Endogámicas LewRESUMEN
Recent data suggest that donor-specific memory T cells (T(mem)) are an independent risk factor for rejection and poor graft function in patients and a major challenge for immunosuppression minimizing strategies. Many tolerance induction protocols successfully proven in small animal models e.g. costimulatory blockade, T cell depletion failed in patients. Consequently, there is a need for more predictive transplant models to evaluate novel promising strategies, such as adoptive transfer of regulatory T cells (Treg). We established a clinically more relevant, life-supporting rat kidney transplant model using a high responder (DA to LEW) recipients that received donor-specific CD4(+)/ 8(+) GFP(+) T(mem) before transplantation to achieve similar pre-transplant frequencies of donor-specific T(mem) as seen in many patients. T cell depletion alone induced long-term graft survival in naïve recipients but could not prevent acute rejection in T(mem)(+) rats, like in patients. Only if T cell depletion was combined with permanent CNI-treatment, the intragraft inflammation, and acute/chronic allograft rejection could be controlled long-term. Remarkably, combining 10 days CNI treatment and adoptive transfer of Tregs (day 3) but not Treg alone also induced long-term graft survival and an intragraft tolerance profile (e.g. high TOAG-1) in T(mem)(+) rats. Our model allows evaluation of novel therapies under clinically relevant conditions.
Asunto(s)
Inhibidores de la Calcineurina , Rechazo de Injerto , Inmunosupresores/farmacología , Trasplante de Riñón , Linfocitos T Reguladores/inmunología , Traslado Adoptivo , Animales , Citometría de Flujo , Memoria Inmunológica , Depleción Linfocítica , Ratas , Ratas Endogámicas Lew , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Despite remarkable progress in organ transplantation through the development of a wealth of immunosuppressive drugs highly effective at controlling acute rejection, two major problems still remain, the loss of transplants due to chronic rejection and the growing number of sensitized recipients due to previous transplants, transfusions or pregnancies. Induction of immune tolerance appears to be the only way to curb this complex situation. Here we describe that a therapy, already successfully used to restore immune tolerance to self-antigens in overt autoimmunity, is effective at promoting transplant tolerance. We demonstrate that a short low-dose course with CD3 antibodies started after transplantation, at the time of effector T cell priming to alloantigens, induces permanent acceptance of fully mismatched islet allografts. Mechanistic studies revealed that antigen-specific regulatory and effector T cells are differentially affected by the treatment. CD3 antibody treatment preferentially induces apoptosis of activated alloreactive T cells which is mandatory for tolerance induction. In contrast, regulatory T cells are relatively spared from CD3 antibody-induced depletion and can transfer antigen-specific tolerance thus arguing for their prominent role in sustaining long-term graft survival.
Asunto(s)
Anticuerpos Monoclonales/farmacología , Complejo CD3/farmacología , Tolerancia Inmunológica/inmunología , Islotes Pancreáticos/inmunología , Tolerancia al Trasplante/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Complejo CD3/inmunología , Trasplante de Células/métodos , Modelos Animales de Enfermedad , Rechazo de Injerto , Supervivencia de Injerto , Tolerancia Inmunológica/efectos de los fármacos , Isoantígenos/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Distribución Aleatoria , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Riesgo , Sensibilidad y Especificidad , Factores de Tiempo , Inmunología del Trasplante/fisiología , Tolerancia al Trasplante/fisiologíaRESUMEN
Children have reduced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rates and a substantially lower risk for developing severe coronavirus disease 2019 compared with adults. However, the molecular mechanisms underlying protection in younger age groups remain unknown. Here we characterize the single-cell transcriptional landscape in the upper airways of SARS-CoV-2-negative (n = 18) and age-matched SARS-CoV-2-positive (n = 24) children and corresponding samples from adults (n = 44), covering an age range of 4 weeks to 77 years. Children displayed higher basal expression of relevant pattern recognition receptors such as MDA5 (IFIH1) and RIG-I (DDX58) in upper airway epithelial cells, macrophages and dendritic cells, resulting in stronger innate antiviral responses upon SARS-CoV-2 infection than in adults. We further detected distinct immune cell subpopulations including KLRC1 (NKG2A)+ cytotoxic T cells and a CD8+ T cell population with a memory phenotype occurring predominantly in children. Our study provides evidence that the airway immune cells of children are primed for virus sensing, resulting in a stronger early innate antiviral response to SARS-CoV-2 infection than in adults.
Asunto(s)
Bronquios/inmunología , Bronquios/virología , COVID-19/inmunología , COVID-19/virología , Inmunidad Innata , SARS-CoV-2/inmunología , Adolescente , Adulto , Anciano , Linfocitos T CD8-positivos/inmunología , Niño , Preescolar , Proteína 58 DEAD Box/metabolismo , Células Dendríticas/inmunología , Células Epiteliales/inmunología , Células Epiteliales/virología , Femenino , Humanos , Lactante , Recién Nacido , Helicasa Inducida por Interferón IFIH1/metabolismo , Macrófagos/inmunología , Masculino , Persona de Mediana Edad , Receptores Inmunológicos/metabolismo , Análisis de la Célula Individual , Linfocitos T Citotóxicos/inmunología , Adulto JovenRESUMEN
Despite novel targeted agents, prognosis of metastatic renal cell cancer (RCC) remains poor, and experimental therapeutic strategies are warranted. Transfection of tumor cells with co-stimulatory molecules and/or cytokines is able to increase immunogenicity. Therefore, in our clinical study, 10 human leukocyte antigen (HLA)-A(*)0201(+) patients with histologically-confirmed progressive metastatic clear cell RCC were immunized repetitively over 22 weeks with 2.5-40 × 10(6) interleukin (IL)-7/CD80 cotransfected allogeneic HLA-A(*)0201(+) tumor cells (RCC26/IL-7/CD80). Endpoints of the study were feasibility, safety, immunological and clinical responses. Vaccination was feasible and safe. In all, 50% of the patients showed stable disease throughout the study; the median time to progression was 18 weeks. However, vaccination with allogeneic RCC26/IL-7/CD80 tumor cells was not able to induce TH1-polarized immune responses. A TH2 cytokine profile with increasing amounts of antigen-specific IL-10 secretion was observed in most of the responding patients. Interferon-γ secretion by patient lymphocytes upon antigen-specific and non-specific stimulation was substantially impaired, both before and during vaccination, as compared with healthy controls. This is possibly due to profound tumor-induced immunosuppression, which may prevent induction of antitumor immune responses by the gene-modified vaccine. Vaccination in minimal residual disease with concurrent depletion of regulatory cells might be one strategy to overcome this limitation.
Asunto(s)
Vacunas contra el Cáncer/uso terapéutico , Carcinoma de Células Renales/terapia , Interleucina-7/inmunología , Neoplasias Renales/terapia , Adulto , Anciano , Antígeno B7-1/metabolismo , Vacunas contra el Cáncer/administración & dosificación , Línea Celular Tumoral , Femenino , Antígenos HLA/análisis , Humanos , Masculino , Persona de Mediana Edad , Linfocitos T/inmunología , TransfecciónRESUMEN
The frequency of delayed function of kidney transplants varies greatly and is associated with quality of graft, donor age and the duration of cold ischemia time. Furthermore, body weight differences between donor and recipient can affect primary graft function, but the underlying mechanism is poorly understood. We transplanted kidney grafts from commensurate body weight (L-WD) or reduced body weight (H-WD) donor rats into syngeneic or allogeneic recipients. Twenty-four hours posttransplantation, serum creatinine levels in H-WD recipients were significantly higher compared to L-WD recipients indicating impaired primary graft function. This was accompanied by upregulation of IL-6 transcription and increased tubular destruction in grafts from H-WD recipients. Using DNA microarray analysis, we detected decreased expression of genes associated with kidney function and an upregulation of other genes such as Cyp3a13, FosL and Trib3. A single application of IL-6 into L-WD recipients is sufficient to impair primary graft function and cause tubular damage, whereas immediate neutralization of IL-6 receptor signaling in H-WD recipients rescued primary graft function with well-preserved kidney graft architecture and a normalized gene expression profile. These findings have strong clinical implication as anti-IL6R treatment of patients receiving grafts from lower-weight donors could be used to improve primary graft function.
Asunto(s)
Peso Corporal/fisiología , Interleucina-6/fisiología , Trasplante de Riñón/fisiología , Transducción de Señal/fisiología , Animales , Apoptosis/fisiología , Creatinina/sangre , Hemo-Oxigenasa 1/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Trasplante de Riñón/patología , Túbulos Renales/patología , Masculino , Modelos Animales , Ratas , Ratas Endogámicas Lew , Ratas EndogámicasRESUMEN
Hepatocyte transplantation (HcTx) is a promising approach for the treatment of metabolic diseases in newborns and children. The most common application route is the portal vein, which is difficult to access in the newborn. Transfemoral access to the splenic artery for HcTx has been evaluated in adults, with trials suggesting hepatocyte translocation from the spleen to the liver with a reduced risk for thromboembolic complications. Using juvenile Göttingen minipigs, we aimed to evaluate feasibility of hepatocyte transplantation by transfemoral splenic artery catheterization, while providing insight on engraftment, translocation, viability, and thromboembolic complications. Four Göttingen Minipigs weighing 5.6 kg to 12.6 kg were infused with human hepatocytes (two infusions per cycle, 1.00E08 cells per kg body weight). Immunosuppression consisted of tacrolimus and prednisolone. The animals were sacrificed directly after cell infusion (n=2), 2 days (n=1), or 14 days after infusion (n=1). The splenic and portal venous blood flow was controlled via color-coded Doppler sonography. Computed tomography was performed on days 6 and 18 after the first infusion. Tissue samples were stained in search of human hepatocytes. Catheter placement was feasible in all cases without procedure-associated complications. Repetitive cell transplantations were possible without serious adverse effects associated with hepatocyte transplantation. Immunohistochemical staining has proven cell relocation to the portal venous system and liver parenchyma. However, cells were neither present in the liver nor the spleen 18 days after HcTx. Immunological analyses showed a response of the adaptive immune system to the human cells. We show that interventional cell application via the femoral artery is feasible in a juvenile large animal model of HcTx. Moreover, cells are able to pass through the spleen to relocate in the liver after splenic artery infusion. Further studies are necessary to compare this approach with umbilical or transhepatic hepatocyte administration.
Asunto(s)
Hepatocitos/trasplante , Hígado/citología , Arteria Esplénica , Animales , Cateterismo/métodos , Trasplante de Células/efectos adversos , Trasplante de Células/métodos , Hepatocitos/citología , Hepatocitos/enzimología , Hepatocitos/inmunología , Humanos , Terapia de Inmunosupresión , Hígado/enzimología , Hígado/patología , Modelos Animales , Vena Porta/citología , Bazo/citología , Bazo/diagnóstico por imagen , Bazo/patología , Arteria Esplénica/citología , Porcinos , Porcinos Enanos , Factores de Tiempo , Tomografía Computarizada por Rayos X , Ultrasonografía DopplerAsunto(s)
Lesión Renal Aguda/genética , Biomarcadores/metabolismo , Fibrosis/diagnóstico , Glomerulonefritis/diagnóstico , Rechazo de Injerto/diagnóstico , Inflamación/diagnóstico , Enfermedades Renales/terapia , Trasplante de Riñón/efectos adversos , Trasplante de Riñón/inmunología , Linfocitos T/inmunología , Femenino , Humanos , MasculinoRESUMEN
Ischemia/reperfusion injury leads to activation of graft endothelial cells (EC), boosting antigraft immunity and impeding tolerance induction. We hypothesized that the complement inhibitor and EC-protectant dextran sulfate (DXS, MW 5000) facilitates long-term graft survival induced by non-depleting anti-CD4 mAb (RIB 5/2). Hearts from DA donor rats were heterotopically transplanted into Lewis recipients treated with RIB 5/2 (20 mg/kg, days-1,0,1,2,3; i.p.) with or without DXS (grafts perfused with 25 mg, recipients treated i.v. with 25 mg/kg on days 1,3 and 12.5 mg/kg on days 5,7,9,11,13,15). Cold graft ischemia time was 20 min or 12 h. Median survival time (MST) was comparable between RIB 5/2 and RIB 5/2+DXS-treated recipients in the 20-min group with >175-day graft survival. In the 12-h group RIB 5/2 only led to chronic rejection (MST = 49.5 days) with elevated alloantibody response, whereas RIB 5/2+DXS induced long-term survival (MST >100 days, p < 0.05) with upregulation of genes related to transplantation tolerance. Analysis of the 12-h group treated with RIB 5/2+DXS at 1-day posttransplantation revealed reduced EC activation, complement deposition and inflammatory cell infiltration. In summary, DXS attenuates I/R-induced acute graft injury and facilitates long-term survival in this clinically relevant transplant model.
Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Sulfato de Dextran/uso terapéutico , Supervivencia de Injerto/efectos de los fármacos , Trasplante de Corazón , Factores Inmunológicos/uso terapéutico , Daño por Reperfusión/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Antígenos CD4 , Linfocitos T CD4-Positivos , Isquemia Fría/efectos adversos , Modelos Animales de Enfermedad , Supervivencia de Injerto/inmunología , Inmunidad Innata , Masculino , Ratas , Ratas Endogámicas , Daño por Reperfusión/etiología , Tolerancia al Trasplante/efectos de los fármacos , Tolerancia al Trasplante/inmunología , Trasplante HomólogoRESUMEN
This prospective randomized pilot study compared the influence of fentanyl-based versus remifentanil-based anaesthesia on cytokine responses and expression of the suppressor of cytokine signalling (SOCS)-3 gene following coronary artery bypass graft surgery. Forty patients were assigned to receive anaesthesia with either intravenous remifentanil (0.3 - 0.6 microg/kg per min; n = 20) or intravenous fentanyl (5 - 10 microg/kg per h; n = 20). Levels of interleukin (IL)-6, IL-10, tumour necrosis factor-alpha and interferon-gamma (IFN-gamma) and the expression of SOCS-3 were measured pre- and post-operatively. The data from 33 of the patients were analysed. The IFN-gamma/IL-10 ratio after concanavalin A stimulation in whole blood cells on post-operative day 1 and SOCS-3 gene expression on post-operative day 2 were significantly lower in the remifentanil group than in the fentanyl group. The time in the intensive care unit was also significantly lower in the remifentanil group. These findings suggest that remifentanil can attenuate the exaggerated inflammatory response that occurs after cardiac surgery with cardiopulmonary bypass. Further clinical trials are required to define the influence of choice of intra-operative opioid on post-operative outcome.
Asunto(s)
Anestésicos Intravenosos/farmacología , Puente de Arteria Coronaria , Citocinas/sangre , Fentanilo/farmacología , Inmunidad Celular/efectos de los fármacos , Piperidinas/farmacología , Anestésicos Intravenosos/administración & dosificación , Fentanilo/administración & dosificación , Expresión Génica/efectos de los fármacos , Humanos , Inmunidad Celular/fisiología , Interferón gamma/sangre , Interleucinas/sangre , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Proyectos Piloto , Piperidinas/administración & dosificación , Estudios Prospectivos , Remifentanilo , Transducción de Señal/efectos de los fármacos , Proteína 3 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas/genética , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Factor de Necrosis Tumoral alfa/sangreRESUMEN
BACKGROUND: Cytotoxic effector molecule expression in human renal allograft biopsies has been closely associated with acute rejection. Here we studied whether intragraft expression of perforin, granzyme B, and Fas ligand correlates with long-term clinical outcome of acute rejection episodes. Furthermore, we examined the relation to histopathology and function of the allograft during rejection. METHODS: Twenty-two human renal biopsies were quantified for mRNA expression of perforin, granzyme B, Fas ligand, and Fas with reverse transcription-polymerase chain reaction. Expression levels were correlated with clinical outcome after 12 months, Banff rejection grades, and allograft function in the course of acute rejection. RESULTS: Only Fas ligand, but not perforin or granzyme B, showed significantly higher up-regulation in seven samples with therapy-resistant acute rejections versus eight samples with therapy-sensitive acute rejection. We found no relation between cytotoxic marker expression and Banff rejection grades or serum creatinine peak levels. CONCLUSIONS: Fas ligand may be useful as an early marker of therapy-resistant acute rejection. Cells that express Fas ligand but not classical soluble cytotoxic molecules might influence clinical outcome of acute rejection episodes.
Asunto(s)
Expresión Génica , Rechazo de Injerto/genética , Trasplante de Riñón , Receptor fas/genética , Enfermedad Aguda , Creatinina/sangre , Resistencia a Medicamentos , Rechazo de Injerto/sangre , Rechazo de Injerto/patología , Granzimas , Humanos , Inmunosupresores/uso terapéutico , Riñón/patología , Glicoproteínas de Membrana/genética , Perforina , Proteínas Citotóxicas Formadoras de Poros , Serina Endopeptidasas/genética , Trasplante Homólogo , Regulación hacia ArribaRESUMEN
BACKGROUND: Fas ligand (FasL) induces apoptosis of cells bearing Fas receptor, and may play a role in the acquisition of immune privilege. We have previously shown that adenovirus (Ad)-mediated FasL gene transfer significantly prolongs survival in a strongly major histocompatibility complex-incompatible rat kidney allograft model. This study analyzes putative mechanisms of FasL-mediated effects, with particular emphasis on Th1 and Th2 immune activation and Bag-1 expression, a Bcl-2-binding anti-apoptotic protein. METHODS: Kidney transplants were performed in Wistar-Furth to Lewis rat combination. Donor kidneys were perfused in situ with Ad-FasL or Ad-beta-Gal, and then transplanted. Kidney allografts were harvested at days 2, 7, and 56 and were evaluated by hematoxylin and eosin and immunohistochemical staining. The expression of FasL, Bag-1, and Th1/Th2 cytokine genes was assessed by Northern blots, Western blots, and competitive template reverse-transcriptase polymerase chain reaction, respectively. RESULTS: Intragraft expression of FasL was enhanced, whereas that of anti-apoptotic Bag-1 gene was diminished throughout, in Ad-FasL-transduced well-functioning renal allografts, compared with Ad-beta-Gal-treated rejecting controls. In parallel, the expression of mRNA coding for IL-2 and IFN-gamma remained depressed, whereas that of IL-4 and IL-10 reciprocally and progressively increased in the Ad-FasL animal group. CONCLUSIONS: Prolonged survival in Ad-FasL-transduced rat renal allograft model correlates with down-regulation of Bag-1, a novel anti-apoptotic gene, and preferential Th2-type cytokine elaboration profile at the graft site. Because Th1-like cells are sensitive to FasL-mediated cytotoxic effects, T-cell apoptosis may preferentially spare Th2-like cells, with resultant prolonged graft survival.
Asunto(s)
Proteínas Portadoras/metabolismo , Citocinas/metabolismo , Técnicas de Transferencia de Gen , Supervivencia de Injerto , Trasplante de Riñón , Glicoproteínas de Membrana/genética , Células Th2/metabolismo , Animales , Apoptosis/fisiología , Proteínas Portadoras/fisiología , Citocinas/genética , Proteínas de Unión al ADN , Regulación hacia Abajo/fisiología , Proteína Ligando Fas , Expresión Génica , Riñón/metabolismo , Riñón/fisiología , Masculino , Glicoproteínas de Membrana/metabolismo , Ratas , Ratas Endogámicas Lew , Ratas Endogámicas WF , Factores de Transcripción , Trasplante HomólogoRESUMEN
Foxp3(+) regulatory T cells (Treg) have a central role for keeping the balance between pro- and anti-inflammatory immune responses against chronically encountered antigens at mucosal sites. However, their antigen specificity especially in humans is largely unknown. Here we used a sensitive enrichment technology for antigen-reactive T cells to directly compare the conventional vs. regulatory CD4(+) T-cell response directed against two ubiquitous mucosal fungi, Aspergillus fumigatus and Candida albicans. In healthy humans, fungus-specific CD4(+)CD25(+)CD127(-)Foxp3(+) Treg are strongly expanded in peripheral blood and possess phenotypic, epigenetic and functional features of thymus-derived Treg. Intriguingly, for A. fumigatus, the strong Treg response contrasts with minimal conventional T-cell memory, indicating selective Treg expansion as an effective mechanism to prevent inappropriate immune activation in healthy individuals. By contrast, in subjects with A. fumigatus allergies, specific Th2 cells were strongly expanded despite the presence of specific Treg. Taken together, we demonstrate a largely expanded Treg population specific for mucosal fungi as part of the physiological human T-cell repertoire and identify a unique capacity of A. fumigatus to selectively generate Treg responses as a potentially important mechanism for the prevention of allergic reactions.