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1.
Cells ; 13(14)2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39056797

RESUMO

BACKGROUND: Solid organ transplantation is hindered by immune-mediated chronic graft dysfunction and the side effects of immunosuppressive therapy. Regulatory T cells (Tregs) are crucial for modulating immune responses post-transplantation; however, the transfer of polyspecific Tregs alone is insufficient to induce allotolerance in rodent models. METHODS: To enhance the efficacy of adoptive Treg therapy, we investigated different immune interventions in the recipients. By utilizing an immunogenic skin transplant model and existing transplantation medicine reagents, we facilitated the clinical translation of our findings. Specifically, antigen-specific Tregs were used. RESULTS: Our study demonstrated that combining the available induction therapies with drug-induced T-cell proliferation due to lymphopenia effectively increased the Treg/T effector ratios. This results in significant Treg accumulation within the graft, leading to long-term tolerance after the transfer of antigen-specific Tregs. Importantly, all the animals achieved operational tolerance, which boosted the presence of adoptively transferred Tregs within the graft. CONCLUSIONS: This protocol offers a means to establish tolerance by utilizing antigen-specific Tregs. These results have promising implications for future trials involving adoptive Treg therapy in organ transplantation.


Assuntos
Transplante de Pele , Linfócitos T Reguladores , Linfócitos T Reguladores/imunologia , Animais , Camundongos , Camundongos Endogâmicos C57BL , Tolerância ao Transplante/imunologia , Transferência Adotiva , Camundongos Endogâmicos BALB C , Tolerância Imunológica , Sobrevivência de Enxerto/imunologia
2.
Hepatol Int ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976227

RESUMO

OBJECTIVE: The detection of autoantibodies is essential to diagnose autoimmune hepatitis (AIH). Particularly in children, specificity of autoantibodies decreases due to lower titers being diagnostic and being present not only in AIH but also in other liver diseases. Recently, quantification of polyreactive IgG (pIgG) for detection of adult AIH showed the highest overall accuracy compared to antinuclear antibodies (ANA), anti-smooth muscle antibodies (anti-SMA), anti-liver kidney microsomal antibodies (anti-LKM) and anti-soluble liver antigen/liver pancreas antibodies (anti-SLA/LP). We aimed to evaluate the diagnostic value of pIgG for pediatric AIH. DESIGN: pIgG, quantified using HIP1R/BSA coated ELISA, and immunofluorescence on rodent tissue sections were performed centrally. The diagnostic fidelity to diagnose AIH was compared to conventional autoantibodies of AIH in training and validation cohorts from a retrospective, European multi-center cohort from nine centers from eight European countries composed of existing biorepositories from expert centers (n = 285). RESULTS: IgG from pediatric AIH patients exhibited increased polyreactivity to multiple protein and non-protein substrates compared to non-AIH liver diseases and healthy children. pIgG had an AUC of 0.900 to distinguish AIH from non-AIH liver diseases. pIgG had a 31-73% higher specificity than ANA and anti-SMA and comparable sensitivity that was 6-20 times higher than of anti-SLA/LP, anti-LC1 and anti-LKM. pIgG had a 21-34% higher accuracy than conventional autoantibodies, was positive in 43-75% of children with AIH and normal IgG and independent from treatment response. CONCLUSION: Detecting pIgG improves the diagnostic evaluation of pediatric AIH compared to conventional autoantibodies, primarily owing to higher accuracy and specificity.

3.
Ann Surg ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041223

RESUMO

OBJECTIVE: Assess the impact of having a living donor on waitlist outcomes and overall survival through an intention-to-treat analysis. BACKGROUND: Living-donor liver transplantation (LDLT) offers an alternative to deceased donation in the face of organ shortage. An as-treated analysis revealed that undergoing LDLT, compared to staying on the waiting list, is associated with improved survival, even at Model for End-stage Liver Disease-sodium (MELD-Na) score of 11. METHODS: Liver transplant candidates listed at the Ajmera Transplant Centre (2000-2021) were categorized as pLDLT (having a potential living donor) or pDDLT (without a living donor). Employing Cox proportional-hazard regression with time-dependent covariates, we evaluated pLDLT's impact on waitlist dropout and overall survival through a risk-adjusted analysis. RESULTS: Of 4,124 candidates, 984 (24%) had potential living donors. The pLDLT group experienced significantly lower overall waitlist dropouts (5.2%vs. 34.4%, P<0.001) and mortality (3.8%vs. 24.4%, P<0.001) compared to the pDDLT group. Possessing a living donor correlated with a 26% decline in the risk of waitlist dropout (adjusted hazard ratio 0.74, 95%CI 0.55-0.99, P=0.042). The pLDLT group also demonstrated superior survival outcomes at 1- (84.9%vs. 80.1%), 5- (77.6%vs. 61.7%), and 10-year (65.6%vs.52.9%) from listing (log-rank P<0.001) with a 35% reduced risk of death (adjusted hazard ratio 0.65, 95%CI 0.56-0.76, P<0.001). Moreover, the predicted hazard ratios consistently remained below 1 across the MELD-Na range 11-26. CONCLUSIONS: Having a potential living donor significantly improves survival in end-stage liver disease patients, even with MELD-Na scores as low as 11. This emphasizes the need to promote awareness and adoption of LDLT in liver transplant programs worldwide.

4.
Diabetes Obes Metab ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39056216

RESUMO

AIM: To investigate the efficacy and safety of glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter-2 (SGLT2) inhibitors in liver transplant (LT) recipients with diabetes. METHODS: A single-centre, retrospective analysis of prospectively collected data from an LT recipient database (1990-2023) was conducted. We included adults with pre-existing diabetes and post-transplant diabetes, newly started on GLP-1RAs and/or SGLT2 inhibitors after LT. Metabolic and biochemical parameters and outcomes were collected for up to 12 months after starting medications and were compared to those in patients receiving dipeptidyl peptidase-4 (DPP-4) inhibitors. Statistical analysis included descriptive statistics and linear mixed models. RESULTS: We included participants on GLP-1RAs (n = 46), SGLT2 inhibitors (n = 87), combination therapy (n = 12), and a DPP-4 inhibitor comparator (n = 217). Both GLP-1RAs and combination therapy decreased mean glycated haemoglobin (HbA1c) levels, and combination therapy remained significant when adjusted for DPP-4 inhibitor treatment (-3.5%, 95% CI [-6.1, -0.95]; p = 0.0089) at 12 months. All three groups had significant decreases in mean weight and body mass index, but these remained significant in the GLP-1RA (-5.2 kg, 95% CI [-8.7, -1.7], p = 0.0039 and 1.99 kg/m2, 95% CI [-3.4, -0.6], p = 0.0048) and combination therapy groups (-5.4 kg, 95% CI [-10.5, -0.36], p = 0.04 and -3.4 kg/m2, 95% CI [-5.5, -1.3], p = 0.0015) when adjusted for DPP-4 inhibitor treatment at 12 months. Alanine aminotransferase levels decreased with GLP-1RA and combination therapy. There were two (1.4%) cases of graft rejection. CONCLUSION: We found that GLP-1RAs, SGLT2 inhibitors, and their combination, led to significant weight loss in LT recipients with diabetes. Combination therapy, in particular, lowered HbA1c and alanine aminotransferase levels compared to DPP-4 inhibitors. Further studies are needed to assess long-term safety and efficacy.

5.
Hum Genomics ; 18(1): 58, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840185

RESUMO

BACKGROUND: Liver transplantation (LT) is offered as a cure for Hepatocellular carcinoma (HCC), however 15-20% develop recurrence post-transplant which tends to be aggressive. In this study, we examined the transcriptome profiles of patients with recurrent HCC to identify differentially expressed genes (DEGs), the involved pathways, biological functions, and potential gene signatures of recurrent HCC post-transplant using deep machine learning (ML) methodology. MATERIALS AND METHODS: We analyzed the transcriptomic profiles of primary and recurrent tumor samples from 7 pairs of patients who underwent LT. Following differential gene expression analysis, we performed pathway enrichment, gene ontology (GO) analyses and protein-protein interactions (PPIs) with top 10 hub gene networks. We also predicted the landscape of infiltrating immune cells using Cibersortx. We next develop pathway and GO term-based deep learning models leveraging primary tissue gene expression data from The Cancer Genome Atlas (TCGA) to identify gene signatures in recurrent HCC. RESULTS: The PI3K/Akt signaling pathway and cytokine-mediated signaling pathway were particularly activated in HCC recurrence. The recurrent tumors exhibited upregulation of an immune-escape related gene, CD274, in the top 10 hub gene analysis. Significantly higher infiltration of monocytes and lower M1 macrophages were found in recurrent HCC tumors. Our deep learning approach identified a 20-gene signature in recurrent HCC. Amongst the 20 genes, through multiple analysis, IL6 was found to be significantly associated with HCC recurrence. CONCLUSION: Our deep learning approach identified PI3K/Akt signaling as potentially regulating cytokine-mediated functions and the expression of immune escape genes, leading to alterations in the pattern of immune cell infiltration. In conclusion, IL6 was identified to play an important role in HCC recurrence.


Assuntos
Carcinoma Hepatocelular , Aprendizado Profundo , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , Transplante de Fígado , Recidiva Local de Neoplasia , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/efeitos adversos , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Regulação Neoplásica da Expressão Gênica/genética , Transcriptoma/genética , Perfilação da Expressão Gênica , Transdução de Sinais/genética , Redes Reguladoras de Genes/genética , Mapas de Interação de Proteínas/genética , Masculino , Feminino , Biomarcadores Tumorais/genética , Pessoa de Meia-Idade
6.
Liver Transpl ; 30(8): 785-795, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38619393

RESUMO

Living donor liver transplantation (LDLT) offers the opportunity to decrease waitlist time and mortality for patients with autoimmune liver disease (AILD), autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis. We compared the survival of patients with a potential living donor (pLDLT) on the waitlist versus no potential living donor (pDDLT) on an intention-to-treat basis. Our retrospective cohort study investigated adults with AILD listed for a liver transplant in our program between 2000 and 2021. The pLDLT group comprised recipients with a potential living donor. Otherwise, they were included in the pDDLT group. Intention-to-treat survival was assessed from the time of listing. Of the 533 patients included, 244 (43.8%) had a potential living donor. Waitlist dropout was higher for the pDDLT groups among all AILDs (pDDLT 85 [29.4%] vs. pLDLT 9 [3.7%], p < 0.001). The 1-, 3-, and 5-year intention-to-treat survival rates were higher for pLDLT versus pDDLT among all AILDs (95.7% vs. 78.1%, 89.0% vs. 70.1%, and 87.1% vs. 65.5%, p < 0.001). After adjusting for covariates, pLDLT was associated with a 38% reduction in the risk of death among the AILD cohort (HR: 0.62, 95% CI: 0.42-0.93 [ p <0.05]), and 60% among the primary sclerosing cholangitis cohort (HR: 0.40, 95% CI: 0.22-0.74 [ p <0.05]). There were no differences in the 1-, 3-, and 5-year post-transplant survival between LDLT and DDLT (AILD: 95.6% vs. 92.1%, 89.9% vs. 89.4%, and 89.1% vs. 87.1%, p =0.41). This was consistent after adjusting for covariates (HR: 0.97, 95% CI: 0.56-1.68 [ p >0.9]). Our study suggests that having a potential living donor could decrease the risk of death in patients with primary sclerosing cholangitis on the waitlist. Importantly, the post-transplant outcomes in this population are similar between the LDLT and DDLT groups.


Assuntos
Colangite Esclerosante , Hepatite Autoimune , Análise de Intenção de Tratamento , Transplante de Fígado , Doadores Vivos , Listas de Espera , Humanos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Transplante de Fígado/estatística & dados numéricos , Feminino , Masculino , Doadores Vivos/estatística & dados numéricos , Estudos Retrospectivos , Pessoa de Meia-Idade , Listas de Espera/mortalidade , Adulto , Resultado do Tratamento , Colangite Esclerosante/cirurgia , Colangite Esclerosante/mortalidade , Colangite Esclerosante/complicações , Hepatite Autoimune/cirurgia , Hepatite Autoimune/mortalidade , Doença Hepática Terminal/cirurgia , Doença Hepática Terminal/mortalidade , Doença Hepática Terminal/diagnóstico , Cirrose Hepática Biliar/cirurgia , Cirrose Hepática Biliar/mortalidade , Doenças Autoimunes/cirurgia , Doenças Autoimunes/mortalidade , Idoso , Fatores de Tempo , Sobrevivência de Enxerto
7.
Am J Transplant ; 24(6): 905-917, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38461883

RESUMO

The Banff Working Group on Liver Allograft Pathology met in September 2022. Participants included hepatologists, surgeons, pathologists, immunologists, and histocompatibility specialists. Presentations and discussions focused on the evaluation of long-term allograft health, including noninvasive and tissue monitoring, immunosuppression optimization, and long-term structural changes. Potential revision of the rejection classification scheme to better accommodate and communicate late T cell-mediated rejection patterns and related structural changes, such as nodular regenerative hyperplasia, were discussed. Improved stratification of long-term maintenance immunosuppression to match the heterogeneity of patient settings will be central to improving long-term patient survival. Such personalized therapeutics are in turn contingent on a better understanding and monitoring of allograft status within a rational decision-making approach, likely to be facilitated in implementation with emerging decision-support tools. Proposed revisions to rejection classification emerging from the meeting include the incorporation of interface hepatitis and fibrosis staging. These will be opened to online testing, modified accordingly, and subject to consensus discussion leading up to the next Banff conference.


Assuntos
Rejeição de Enxerto , Transplante de Fígado , Humanos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto , Aloenxertos
8.
J Cardiothorac Vasc Anesth ; 38(4): 1015-1030, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38185566

RESUMO

Liver transplantation (LT) is the second most performed solid organ transplant. Coronary artery disease (CAD) is a critical consideration for LT candidacy, particularly in patients with known CAD or risk factors, including metabolic dysfunction associated with steatotic liver disease. The presence of severe CAD may exclude patients from LT; therefore, precise preoperative evaluation and interventions are necessary to achieve transplant candidacy. Cardiovascular complications represent the earliest nongraft-related cause of death post-transplantation. Timely intervention to reduce cardiovascular events depends on adequate CAD screening. Coronary disease screening in end-stage liver disease is challenging because standard noninvasive CAD screening tests have low sensitivity due to hyperdynamic state and vasodilatation. As a result, there is overuse of invasive coronary angiography to exclude severe CAD. Coronary artery calcium scoring using a computed tomography scan is a tool for the prediction of cardiovascular events, and can be used to achieve risk stratification in LT candidates. Recent literature shows that qualitative assessment on both noncontrast- and contrast-enhanced chest computed tomography can be used instead of calcium score to assess the presence of coronary calcium. With increasing prevalence, protocols to address CAD in LT candidates must be reconsidered. Percutaneous coronary intervention could allow a shorter duration of dual-antiplatelet therapy in simple lesions, with safer perioperative outcomes. Hybrid coronary revascularization is an option for high-risk LT candidates with multivessel disease nonamenable to percutaneous coronary intervention. The objective of this review is to evaluate existing methods for preoperative cardiovascular risk stratification, and to describe interventions before surgery to optimize patient outcomes and reduce cardiovascular event risk.


Assuntos
Doenças Cardiovasculares , Doença da Artéria Coronariana , Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/complicações , Cálcio/metabolismo , Fatores de Risco , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/cirurgia , Doença da Artéria Coronariana/epidemiologia , Medição de Risco/métodos , Angiografia Coronária/métodos , Fatores de Risco de Doenças Cardíacas
9.
Ann Hepatol ; 29(1): 101168, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37858675

RESUMO

INTRODUCTION AND OBJECTIVES: Recurrent cirrhosis complicates 10-30% of Liver transplants (LT) and can lead to consideration for re-transplantation. We evaluated the trajectories of relisted versus primary listed patients on the waitlist using a competing risk framework. MATERIALS AND METHODS: We retrospectively examined 1,912 patients listed for LT at our centre between from 2012 to 2020. Cox proportional hazard models were used to assess overall survival (OS) by listing type and competing risk analysis Fine-Gray models were used to assess cumulative incidence of transplant by listing type. RESULTS: 1,731 patients were included (104 relisted). 44.2% of relisted patients received exception points vs. 19.8% of primary listed patients (p<0.001). Patients relisted without exceptions, representing those with graft cirrhosis, had the worst OS (HR: 4.17, 95%CI 2.63 - 6.67, p=<0.0001) and lowest instantaneous rate of transplant (HR: 0.56, 95%CI 0.38 - 0.83, p=0.006) than primary listed with exception points. On multivariate analysis listing type, height, bilirubin and INR were associated with cumulative incidence of transplant, while listing type, bilirubin, INR, sodium, creatinine were associated with OS. Within relisted patients, there was a trend towards higher mortality (HR: 1.79, 95%CI 0.91 - 3.52, p=0.08) and low transplant incidence (HR: 0.51, 95%CI 0.22 - 1.15, p=0.07) for graft cirrhosis vs other relisting indications. CONCLUSIONS: Patients relisted for LT are carefully curated and comprise a minority of the waitlist population. Despite their younger age, they have worse liver/kidney function, poor waitlist survival, and decreased transplant incidence suggesting the need for early relisting, while considering standardized exception points.


Assuntos
Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Cirrose Hepática/cirurgia , Modelos de Riscos Proporcionais , Listas de Espera , Bilirrubina
11.
Liver Transpl ; 30(3): 254-261, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-37772886

RESUMO

Since 2018, our program has utilized specific psychosocial criteria and a multidisciplinary approach to assess patients for liver transplant due to alcohol-associated liver disease (ALD), rather than the 6-month abstinence rule alone. If declined based on these criteria, specific recommendations are provided to patients and their providers regarding goals for re-referral to increase the potential for future transplant candidacy. Recommendations include engagement in treatment for alcohol use disorder, serial negative biomarker testing, and maintenance of abstinence from alcohol. In our current study, we evaluate the outcomes of patients with ALD, who were initially declined upon assessment and re-referred to our program. This is a retrospective cohort study that includes 98 patients with ALD, who were previously declined for liver transplantation and were subsequently re-referred for liver transplant assessment between May 1, 2018, and December 31, 2021. We assess the outcomes of patients who were re-referred including acceptance for transplantation following a second assessment. Of the 98 patients who were re-referred, 46 (46.9%) fulfilled the recommendations made and proceeded to further medical evaluation. Nine were eventually transplanted; others are listed and are waiting for transplant. The presence of a partner was independently associated with a higher rate of acceptance (OR 0.16, 95% CI: 0.03-0.97, p = 0.05). Most of the patients who did not proceed further (n = 52) were declined again due to ALD contraindications (n = 33, 63.4%), including ongoing drinking and lack of engagement in recommended addiction treatment. Others had medical contraindications (11.2%), clinically improved (6.1%), had adherence issues (5.1%), or lack of adequate support (2%). Patients with ALD previously declined for a liver transplant can be re-referred and successfully accepted for transplantation by fulfilling the recommendations made by the multidisciplinary team. Important factors including ongoing abstinence, engagement in addiction treatment, and social support are key for successful acceptance.


Assuntos
Alcoolismo , Hepatopatias Alcoólicas , Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Hepatopatias Alcoólicas/cirurgia , Hepatopatias Alcoólicas/complicações , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Alcoolismo/complicações
12.
Can J Surg ; 66(6): E561-E571, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38016726

RESUMO

BACKGROUND: Advanced donor age paired with donation after cardiac death (DCD) increases the risk of transplantation, precluding widespread use of grafts from such donors worldwide. Our aim was to analyze outcomes of liver transplantation using grafts from older DCD donors and donation after brain death (DBD) donors. METHODS: Patients who underwent liver transplantation using grafts from deceased donors between January 2016 and December 2021 were included in the study. Short-and long-term outcomes were analyzed for 4 groups of patients: those who received DCD and DBD grafts from younger (< 50 yr) and older (≥ 50 yr) donors. RESULTS: Of the 807 patients included in the analysis, 44.7% (n = 361) of grafts were received from older donors, with grafts for older DCD donors comprising 4.7% of the total cohort (n = 38). Patients who received grafts from older donors had a lower incidence of biliary strictures than those who received grafts from younger donors (7.9% v. 20.0% for DCD donation, p = 0.14, and 4.9% v. 6.8% for DBD donation, p = 0.34), with a significantly lower incidence of ischemic-type biliary strictures in patients who received grafts from older versus younger DCD donors (2.6% v. 18.0%, p = 0.04). There was no difference in 1- and 3-year graft survival rates among patients who received grafts from older and younger DCD donors (92.1% v. 90.8% and 80.2% v. 80.9%, respectively) and those who received grafts from older and younger DBD donors (90.1% v. 93.2% and 85.3% v. 84.4%, respectively) (p = 0.85). Pretransplantation admission to the intensive care unit (hazard ratio [HR] 9.041, p < 0.001) and nonalcoholic steatohepatitis (HR 2.197, p = 0.02) were found to significantly affect survival of grafts from older donors. CONCLUSION: Donor age alone should not be the criterion to determine the acceptability of grafts in liver transplantation. With careful selection criteria, older DCD donors could make a valuable contribution to expanding the liver donor pool, with grafts that produce comparable results to those obtained with standard-criteria grafts.


Assuntos
Transplante de Fígado , Obtenção de Tecidos e Órgãos , Humanos , Constrição Patológica , Estudos Retrospectivos , Doadores Vivos , Doadores de Tecidos , Morte , Morte Encefálica
13.
Transplant Direct ; 9(11): e1547, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37854023

RESUMO

Despite advances in posttransplant care, long-term outcomes for liver transplant recipients remain unchanged. Approximately 25% of recipients will advance to graft cirrhosis and require retransplantation. Graft fibrosis progresses in the context of de novo or recurrent disease. Recurrent hepatitis C virus infection was previously the most important cause of graft failure but is now curable in the majority of patients. However, with an increasing prevalence of obesity and diabetes and nonalcoholic fatty liver disease as the most rapidly increasing indication for liver transplantation, metabolic dysfunction-associated liver injury is anticipated to become an important cause of graft fibrosis alongside alloimmune hepatitis and alcoholic liver disease. To better understand the landscape of the graft fibrosis literature, we summarize the associated epidemiology, cause, potential mechanisms, diagnosis, and complications. We additionally highlight the need for better noninvasive methods to ameliorate the management of graft fibrosis. Some examples include leveraging the microbiome, genetic, and machine learning methods to address these limitations. Overall, graft fibrosis is routinely seen by transplant clinicians, but it requires a better understanding of its underlying biology and contributors that can help inform diagnostic and therapeutic practices.

14.
Cells ; 12(16)2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37626926

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disease that remains uncured. Its pathogenesis is characterized by the formation of ß-amyloid (Aß) plaques. The use of antigen-specific regulatory T cells (Tregs) through adoptive transfer has shown promise for the treatment of many inflammatory diseases, although the effectiveness of polyspecific Tregs is limited. Obtaining a sufficient number of antigen-specific Tregs from patients remains challenging. AIMS AND METHODS: To address this problem, we used an antibody-like single-chain variable fragment from a phage library and subsequently generated a chimeric antigen receptor (CAR) targeting ß-amyloid. RESULTS: The ß-amyloid-specific CARs obtained were stimulated by both recombinant and membrane-bound Aß isolated from the murine brain. The generated CAR-Tregs showed a normal Treg phenotype, were antigen-specific activatable, and had suppressive capacity. CONCLUSION: This study highlights the potential of CAR technology to generate antigen-specific Tregs and presents novel approaches for developing functional CARs.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Receptores de Antígenos Quiméricos , Anticorpos de Cadeia Única , Animais , Camundongos , Doença de Alzheimer/terapia , Peptídeos beta-Amiloides
15.
Front Immunol ; 14: 1215868, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533865

RESUMO

Introduction: Torque teno virus (TTV) replication is controlled by immune status, mirroring a degree of immunosuppression after solid organ transplantation. TTV viraemia (TTVv) was associated with acute cellular rejection and infection within the first year after liver transplantation (LT). Long-term data on TTV after LT and correlation with graft injury from protocol biopsies are limited. Methods: One hundred plasma samples paired with graft biopsies from a prospective single-center biorepository were analyzed. Results: The median time post-LT was 23 months (range, 2-298). TTVv was detectable in 97%. TTVv decreased over time after LT and showed a significant decline from year 1 to later time points. Hence, TTVv correlated negatively with histologic liver fibrosis (liver allograft fibrosis and Ishak scores) and positively with the overall immunosuppression degree quantified by an immunosuppression score in the first year after LT. There was no association with dosages or trough levels of single immunosuppressants. The pharmacodynamic marker TTVv did not correlate with pharmacokinetic assessments of immunosuppression degree [calcineurin inhibitor (CNI) trough levels or immunosuppressant dosages]-our clinical gold standards to guide immunosuppressive therapy. TTVv was independently associated with histologically proven liver fibrosis after LT in the first year after LT in multivariate analysis. Discussion: The independent association of histological graft fibrosis with lower TTVv in year 1 underscores that a pharmacodynamic marker would be preferable to individualize immunosuppression after LT. However, a high variability of TTVv at the low immunosuppression doses given after the first year precludes TTV as a clinically useful marker after LT in the long-term liver transplant recipients.


Assuntos
Transplante de Fígado , Torque teno virus , Humanos , Transplante de Fígado/efeitos adversos , Viremia , Estudos Prospectivos , Cirrose Hepática/etiologia , Cirrose Hepática/cirurgia , Imunossupressores/efeitos adversos
16.
Hepatol Commun ; 7(8)2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37534935

RESUMO

BACKGROUND: Liver transplantation (LT) is frequently lifesaving for people living with primary sclerosing cholangitis (PSC). However, patients are waitlisted for LT according to the model for end-stage liver disease-sodium (MELD-Na) score, which may not accurately reflect the burden of living with PSC. We sought to describe and analyze the clinical trajectory for patients with PSC referred for LT, in a mixed deceased donor/living donor transplant program. METHODS: This was a retrospective cohort study from November 2012 to December 2019, including all patients with PSC referred for assessment at the University Health Network Liver Transplant Clinic. Patients who required multiorgan transplant or retransplantation were excluded. Liver symptoms, hepatobiliary malignancy, MELD-Na progression, and death were abstracted from chart review. Competing risk analysis was used for timing of LT, transplant type, and death. RESULTS: Of 172 PSC patients assessed, 84% (n = 144) were listed of whom 74% were transplanted. Mean age was 47.6 years, and 66% were male. Overall mortality was 18.2% at 2 years. During the follow-up, 16% (n = 23) were removed from the waitlist for infection, clinical deterioration, liver-related mortality or new cancer; 3 had clinical improvement. At listing, 82% (n = 118) had a potential living donor (pLD). Patients with pLD had significantly lower waitlist and liver-related waitlist mortality (HR 0.20, p<0.001 and HR 0.17, p<0.001, respectively), and higher rates of transplantation (HR 1.83, p = 0.05). Exception points were granted to 13/172 (7.5%) patients. CONCLUSIONS: In a high-volume North American LT center, most patients with PSC assessed for transplant were listed and subsequently transplanted. However, this was a consequence of patients engaging in living donor transplantation. Our findings support the concern from patients with PSC that MELD-Na allocation does not adequately address their needs.


Assuntos
Colangite Esclerosante , Doença Hepática Terminal , Transplante de Fígado , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Transplante de Fígado/efeitos adversos , Doadores Vivos , Doença Hepática Terminal/cirurgia , Colangite Esclerosante/cirurgia , Estudos Retrospectivos , Índice de Gravidade de Doença
17.
JAMA Netw Open ; 6(7): e2322048, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37410459

RESUMO

Importance: The potential association of low-volume paracentesis of less than 5 L with complications in patients with ascites remains unclear, and individuals with cirrhosis and refractory ascites (RA) treated with devices like Alfapump or tunneled-intraperitoneal catheters perform daily low-volume drainage without albumin substitution. Studies indicate marked differences regarding the daily drainage volume between patients; however, it is currently unknown if this alters the clinical course. Objective: To determine whether the incidence of complications, such as hyponatremia or acute kidney injury (AKI), is associated with the daily drainage volume in patients with devices. Design, Setting, and Participants: This retrospective cohort study of patients with liver cirrhosis, RA, and a contraindication for a transjugular intrahepatic portosystemic shunt who received either device implantation or standard of care (SOC; ie, repeated large-volume paracentesis with albumin infusion), and were hospitalized between 2012 and 2020 were included. Data were analyzed from April to October 2022. Interventions: Daily ascites volume removed. Main outcomes and Measures: The primary end points were 90-day incidence of hyponatremia and AKI. Propensity score matching was performed to match and compare patients with devices and higher or lower drainage volumes to those who received SOC. Results: Overall, 250 patients with RA receiving either device implantation (179 [72%] patients; 125 [70%] male; 54 [30%] female; mean [SD] age, 59 [11] years) or SOC (71 [28%] patients; 41 [67%] male; 20 [33%] female; mean [SD] age, 54 [8]) were included in this study. A cutoff of 1.5 L/d or more was identified to estimate hyponatremia and AKI in the included patients with devices. Drainage of 1.5 L/d or more was associated with hyponatremia and AKI, even after adjusting for various confounders (hazard ratio [HR], 2.17 [95% CI, 1.24-3.78]; P = .006; HR, 1.43 [95% CI, 1.01-2.16]; P = .04, respectively). Moreover, patients with taps of 1.5 L/d or more and less than 1.5 L/d were matched with patients receiving SOC. Those with taps of 1.5 L/d or more had a higher risk of hyponatremia and AKI compared with those receiving SOC (HR, 1.67 [95% CI, 1.06-2.68]; P = .02 and HR, 1.51 [95% CI, 1.04-2.18]; P = .03), while patients with drainage of less than 1.5 L/d did not show an increased rate of complications compared with those receiving SOC. Conclusions and Relevance: In this cohort study, clinical complications in patients with RA performing low-volume drainage without albumin infusion were associated with the daily volume drained. Based on this analysis, physicians should be cautious in patients performing drainage of 1.5 L/d or more without albumin infusion.


Assuntos
Injúria Renal Aguda , Hiponatremia , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Paracentese/efeitos adversos , Ascite/epidemiologia , Ascite/etiologia , Ascite/terapia , Estudos de Coortes , Estudos Retrospectivos , Hiponatremia/epidemiologia , Hiponatremia/etiologia , Cirrose Hepática/complicações , Albuminas , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia
18.
Liver Cancer ; 12(2): 129-144, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37325488

RESUMO

Background: Checkpoint inhibitors act on exhausted CD8+ T cells and restore their effector function in chronic infections and cancer. The underlying mechanisms of action appear to differ between different types of cancer and are not yet fully understood. Methods: Here, we established a new orthotopic HCC model to study the effects of checkpoint blockade on exhausted CD8+ tumor-infiltrating lymphocytes (TILs). The tumors expressed endogenous levels of HA, which allowed the study of tumor-specific T cells. Results: The induced tumors developed an immune-resistant TME in which few T cells were found. The few recovered CD8+ TILs were mostly terminally exhausted and expressed high levels of PD-1. PD-1/CTLA-4 blockade resulted in a strong increase in the number of CD8+ TILs expressing intermediate amounts of PD-1, also called progenitor-exhausted CD8+ TILs, while terminally exhausted CD8+ TILs were almost absent in the tumors of treated mice. Although transferred naïve tumor-specific T cells did not expand in the tumors of untreated mice, they expanded strongly after treatment and generated progenitor-exhausted but not terminally exhausted CD8+ TILs. Unexpectedly, progenitor-exhausted CD8+ TILs mediated the antitumor response after treatment with minimal changes in their transcriptional profile. Conclusion: In our model, few doses of checkpoint inhibitors during the priming of transferred CD8+ tumor-specific T cells were sufficient to induce tumor remission. Therefore, PD-1/CTLA-4 blockade has an ameliorative effect on the expansion of recently primed CD8+ T cells while preventing their development into terminally exhausted CD8+ TILs in the TME. This finding could have important implications for future T-cell therapies.

19.
Sci Rep ; 13(1): 10038, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340049

RESUMO

Autoantibodies are the diagnostic hallmark of autoimmune liver diseases. Indirect immunofluorescence (IFT) is the reference method for the detection of anti-mitochondrial antibodies (AMA) and anti-liver kidney microsomal type-1 (anti-LKM1) antibodies, and inhibition ELISA (iELISA) for anti-soluble liver antigen (anti-SLA) antibodies. Given the complexity of these techniques, commercial ELISAs have emerged as a practical alternative, but without head-to-head validations. This study evaluated the agreement between three commercial ELISAs and the reference techniques and the impact of polyreactive immunoglobulin G (pIgG), a recently described phenomenon in autoimmune hepatitis, on commercial ELISAs. Inter-rater reliability was assessed using Cohen-Kappa coefficient (κ). Forty-eight, 46, and 66 samples were analyzed for AMA, anti-LKM1, and anti-SLA, respectively. For AMA, one commercial assay showed high agreement (κ = 0.91 (0.78-1.00)) with the reference method, while the other two showed weak or moderate agreement. For anti-LKM1, only one commercial assay showed high agreement (κ = 0.86 (0.71-1.0)). For anti-SLA antibodies only moderate agreement was achieved (κ up to 0.71 (0.52-0.89)). There was a trend towards higher pIgG levels in false-positives in the commercial ELISAs. Patients with high suspicion of autoimmune liver diseases should be referred to reference laboratories with the capacity of performing gold standard methods if the initial ELISA-based screening was performed.


Assuntos
Hepatite Autoimune , Hepatopatias , Humanos , Reprodutibilidade dos Testes , Hepatite Autoimune/diagnóstico , Mitocôndrias , Rim
20.
Cells ; 12(11)2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37296574

RESUMO

Adoptive transfer of antigen-specific regulatory T cells (Tregs) has shown promising results in the treatment of autoimmune diseases; however, the use of polyspecific Tregs has limited effects. However, obtaining a sufficient number of antigen-specific Tregs from patients with autoimmune disorders remains challenging. Chimeric antigen receptors (CARs) provide an alternative source of T cells for novel immunotherapies that redirect T cells independently of the MHC. In this study, we aimed to generate antibody-like single-chain variable fragments (scFv) and subsequent CARs against tetraspanin 7 (TSPAN7), a membrane protein highly expressed on the surface of pancreatic beta cells, using phage display technology. We established two methods for generating scFvs against TSPAN7 and other target structures. Moreover, we established novel assays to analyze and quantify their binding abilities. The resulting CARs were functional and activated specifically by the target structure, but could not recognize TSPAN7 on the surface of beta cells. Despite this, this study demonstrates that CAR technology is a powerful tool for generating antigen-specific T cells and provides new approaches for generating functional CARs.


Assuntos
Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T Reguladores , Imunoterapia , Tetraspaninas
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