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1.
Liver Transpl ; 30(4): 367-375, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37639285

RESUMO

The exception point system for liver allocation in the United States allows for additional waitlist priority for candidates where the Model for End-Stage Liver Disease or Pediatric End-stage Liver Disease does not effectively represent their urgency or need for a transplant. In May 2019, the review process for liver exception cases transitioned from 11 Regional Review Boards (RRBs) to 1 National Liver Review Board (NLRB), intended to increase consistency nationwide, improve efficiency, and balance transplant access for candidates with and without exception scores. This report provides a review of liver exception request and review practices, waitlist outcomes, and transplant activity in the first 2 years after implementation of the NLRB and acuity circle-based distribution in the United States. We compared initial and extension exception request forms submitted from May 13, 2017 to May 13, 2019 (prepolicy or RRB era) to the period from February 4, 2020 to February 3, 2022 (postpolicy or NLRB era). During this time, the NLRB reviewed 10,083 initial exception requests and 12,686 extension requests. Notable postpolicy highlights include (1) an increase in the proportion of initial and extension requests that were automatically approved instead of manually reviewed; (2) a decrease in the overall approval rates of initial exception requests (87.8% for adult HCC, 64.3% for adult other diagnoses, and 71.5% for pediatric); and (3) reduction in the time from exception request submission to adjudication to a median of 3.73 days. The proportions of waitlist registration and deceased donor liver transplants for patients with exception scores decreased, and waitlist outcomes between patients with and without exception scores are now comparable. Implementation of the NLRB improved efficiency, reduced case workloads, and standardized criteria for exception cases, with similar waitlist outcomes between patients with and without exception scores and improved equity in terms of access to liver transplants.


Assuntos
Carcinoma Hepatocelular , Doença Hepática Terminal , Neoplasias Hepáticas , Transplante de Fígado , Obtenção de Tecidos e Órgãos , Adulto , Humanos , Criança , Estados Unidos , Carcinoma Hepatocelular/diagnóstico , Doença Hepática Terminal/cirurgia , Neoplasias Hepáticas/diagnóstico , Transplante de Fígado/efeitos adversos , Seleção de Pacientes , Índice de Gravidade de Doença , Doadores Vivos , Listas de Espera
2.
Clin Transplant ; 38(1): e15172, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37897198

RESUMO

PURPOSE: Our study hypothesis was that once daily dosing of extended-release tacrolimus (XRT) would be a safe and effective immunosuppression (IS) with the potential to decrease adverse events (AEs) associated with immediate release tacrolimus (IRT) after liver transplantation (LT). METHODS: All patients receiving LT at our center received rabbit anti-thymocyte globulin (RATG) induction therapy. Eligible patients were randomized in a 1:1 fashion to receive either XRT or IRT. Antimicrobial prophylaxis was the same between arms, and both groups received an antimetabolite for the first 6 months following LT. Patients were then followed at pre-determined study intervals for the following year after LT. We administered the RAND-36SF survey to assess patient's health-related quality of life at pre-determined intervals. All analysis was performed with an intention to treat basis. RESULTS: We screened 194 consecutive patients and enrolled 110. Our control and study arms were well matched. Transplant characteristics were similar between groups. At all timepoints, both arms had similar serum creatinine and estimated glomerular filtration rate (eGFR), calculated by MDRD6 equation, with post-transplant GFRs between 60 and 70 mL/min/1.73 m2 . Tacrolimus trough levels were similar between arms. The XRT arm had fewer AEs (166) and fewer serious AEs (70) compared to IRT (201 and 99, respectively). AEs most commonly were renal, infectious, or gastrointestinal in nature. While not statistically significant, XRT was held temporarily (25 vs. 35 cases) or discontinued (3 vs. 11 cases) less frequently than IRT and had fewer instances of rejection (7 vs. 12 cases). CONCLUSION: This analysis showed that XRT is safe and effective as de novo maintenance IS in a steroid-free protocol with RATG.


Assuntos
Transplante de Fígado , Tacrolimo , Humanos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Transplante de Fígado/efeitos adversos , Estudos Prospectivos , Qualidade de Vida , Esteroides , Tacrolimo/administração & dosagem , Tacrolimo/efeitos adversos , Preparações de Ação Retardada
3.
Kidney Int ; 103(6): 1077-1092, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36863444

RESUMO

Chronic allograft dysfunction (CAD), characterized histologically by interstitial fibrosis and tubular atrophy, is the major cause of kidney allograft loss. Here, using single nuclei RNA sequencing and transcriptome analysis, we identified the origin, functional heterogeneity, and regulation of fibrosis-forming cells in kidney allografts with CAD. A robust technique was used to isolate individual nuclei from kidney allograft biopsies and successfully profiled 23,980 nuclei from five kidney transplant recipients with CAD and 17,913 nuclei from three patients with normal allograft function. Our analysis revealed two distinct states of fibrosis in CAD; low and high extracellular matrix (ECM) with distinct kidney cell subclusters, immune cell types, and transcriptional profiles. Imaging mass cytometry analysis confirmed increased ECM deposition at the protein level. Proximal tubular cells transitioned to an injured mixed tubular (MT1) phenotype comprised of activated fibroblasts and myofibroblast markers, generated provisional ECM which recruited inflammatory cells, and served as the main driver of fibrosis. MT1 cells in the high ECM state achieved replicative repair evidenced by dedifferentiation and nephrogenic transcriptional signatures. MT1 in the low ECM state showed decreased apoptosis, decreased cycling tubular cells, and severe metabolic dysfunction, limiting the potential for repair. Activated B, T and plasma cells were increased in the high ECM state, while macrophage subtypes were increased in the low ECM state. Intercellular communication between kidney parenchymal cells and donor-derived macrophages, detected several years post-transplantation, played a key role in injury propagation. Thus, our study identified novel molecular targets for interventions aimed to ameliorate or prevent allograft fibrogenesis in kidney transplant recipients.


Assuntos
Nefropatias , Transplante de Rim , Humanos , Transplante de Rim/efeitos adversos , Transcriptoma , Aloenxertos/patologia , Rim/patologia , Nefropatias/patologia , Fibrose , Perfilação da Expressão Gênica
4.
Am J Transplant ; 23(9): 1434-1445, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37201755

RESUMO

Operational tolerance (OT) after kidney transplantation is defined as stable graft acceptance without the need for immunosuppression therapy. However, it is not clear which cellular and molecular pathways are driving tolerance in these patients. In this first-of-its-kind pilot study, we assessed the immune landscape associated with OT using single-cell analyses. Peripheral mononuclear cells from a kidney transplant recipient with OT (Tol), 2 healthy individuals (HC), and a kidney transplant recipient with normal kidney function on standard-of-care immunosuppression (SOC) were evaluated. The immune landscape of the Tol was drastically different from that of SOC and emerged closer to the profile of HC. TCL1A+ naive B cells and LSGAL1+ regulatory T cells (Tregs) were in higher proportions in Tol. We were unable to identify the Treg subcluster in SOC. The ligand-receptor analysis in HC and Tol identified interactions between B cells, and Tregs that enhance the proliferation and suppressive function of Tregs. SOC reported the highest proportion of activated B cells with more cells in the G2M phase. Our single-cell RNA sequencing study identified the mediators of tolerance; however, it emphasizes the requirement of similar investigations on a larger cohort to reaffirm the role of immune cells in tolerance.


Assuntos
Transplante de Rim , Humanos , Transplante de Rim/efeitos adversos , Leucócitos Mononucleares , Projetos Piloto , Rejeição de Enxerto/etiologia , Tolerância Imunológica , Linfócitos T Reguladores , Análise de Sequência de RNA , Tolerância ao Transplante
5.
Am J Physiol Gastrointest Liver Physiol ; 324(3): G207-G218, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36648139

RESUMO

Treatment of advanced liver disease using surgical modalities is possible due to the liver's innate ability to regenerate following resection. Several key cellular events in the regenerative process converge at the mitochondria, implicating their crucial roles in liver regeneration. Mitochondria enable the regenerating liver to meet massive metabolic demands by coordinating energy production to drive cellular proliferative processes and vital homeostatic functions. Mitochondria are also involved in terminating the regenerative process by mediating apoptosis. Studies have shown that attenuation of mitochondrial activity results in delayed liver regeneration, and liver failure following resection is associated with mitochondrial dysfunction. Emerging mitochondria therapy (i.e., mitotherapy) strategies involve isolating healthy donor mitochondria for transplantation into diseased organs to promote regeneration. This review highlights mitochondria's inherent role in liver regeneration.


Assuntos
Hepatectomia , Regeneração Hepática , Fígado/metabolismo , Mitocôndrias , Proliferação de Células
6.
Am J Transplant ; 22(11): 2515-2528, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35730259

RESUMO

With the development of novel prognostic tools derived from omics technologies, transplant medicine is entering the era of precision medicine. Currently, there are no established predictive biomarkers for posttransplant kidney function. A total of 270 deceased donor pretransplant kidney biopsies were collected and posttransplant function was prospectively monitored. This study first assessed the utility of pretransplant gene expression profiles in predicting 24-month outcomes in a training set (n = 174). Nearly 600 differentially expressed genes were associated with 24-month graft function. Grafts that progressed to low function at 24 months exhibited upregulated immune responses and downregulated metabolic processes at pretransplantation. Using penalized logistic regression modeling, a 55 gene model area under the receiver operating curve (AUROC) for 24-month graft function was 0.994. Gene expression for a subset of candidate genes was then measured in an independent set of pretransplant biopsies (n = 96) using quantitative polymerase chain reaction. The AUROC when using 13 genes with three donor characteristics (age, race, body mass index) was 0.821. Subsequently, a risk score was calculated using this combination for each patient in the validation cohort, demonstrating the translational feasibility of using gene markers as prognostic tools. These findings support the potential of pretransplant transcriptomic biomarkers as novel instruments for improving posttransplant outcome predictions and associated management.


Assuntos
Transplante de Rim , Transcriptoma , Humanos , Transplante de Rim/efeitos adversos , Doadores de Tecidos , Rim , Biomarcadores/metabolismo
7.
Am J Transplant ; 22(2): 599-609, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34613666

RESUMO

Kidney transplantation (KT) from deceased donors with hepatitis C virus (HCV) into HCV-negative recipients has become more common. However, the risk of complications such as BK polyomavirus (BKPyV) remains unknown. We assembled a retrospective cohort at four centers. We matched recipients of HCV-viremic kidneys to highly similar recipients of HCV-aviremic kidneys on established risk factors for BKPyV. To limit bias, matches were within the same center. The primary outcome was BKPyV viremia ≥1000 copies/ml or biopsy-proven BKPyV nephropathy; a secondary outcome was BKPyV viremia ≥10 000 copies/ml or nephropathy. Outcomes were analyzed using weighted and stratified Cox regression. The median days to peak BKPyV viremia level was 119 (IQR 87-182). HCV-viremic KT was not associated with increased risk of the primary BKPyV outcome (HR 1.26, p = .22), but was significantly associated with the secondary outcome of BKPyV ≥10 000 copies/ml (HR 1.69, p = .03). One-year eGFR was similar between the matched groups. Only one HCV-viremic kidney recipient had primary graft loss. In summary, HCV-viremic KT was not significantly associated with the primary outcome of BKPyV viremia, but the data suggested that donor HCV might elevate the risk of more severe BKPyV viremia ≥10 000 copies/ml. Nonetheless, one-year graft function for HCV-viremic recipients was reassuring.


Assuntos
Vírus BK , Transplante de Rim , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Hepacivirus , Humanos , Transplante de Rim/efeitos adversos , Estudos Retrospectivos , Infecções Tumorais por Vírus/etiologia , Viremia
8.
Clin Transplant ; 36(10): e14681, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35567584

RESUMO

BACKGROUND: It has long been debated whether cava anastomosis should be performed with the piggyback technique or cava replacement, with or without veno-venous bypass (VVB), with or without temporary portocaval shunt (PCS) in the setting of liver transplantation. OBJECTIVES: To identify whether different cava anastomotic techniques and other maneuvers benefit the recipient regarding short-term outcomes and to provide international expert panel recommendations. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: A systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel (CRD42021240979). RESULTS: Of 3205 records screened, 307 publications underwent full-text assessment for eligibility and 47 were included in qualitative synthesis. Four studies were randomized control trials. Eighteen studies were comparative. The remaining 25 were single-center retrospective noncomparative studies. CONCLUSION: Based on existing data and expert opinion, the panel cannot recommend one cava reconstruction technique over another, rather the surgical approach should be based on surgeon preference and center dependent, with special consideration toward patient circumstances (Quality of evidence: Low | Grade of Recommendation: Strong). The panel recommends against routine use of vevo-venous bypass (Quality of evidence: Very Low | Grade of Recommendation: Strong) and against the routine use of temporary porto-caval shunt (Quality of evidence: Very Low | Grade of Recommendation: Strong).


Assuntos
Kava , Transplante de Fígado , Humanos , Transplante de Fígado/métodos , Estudos Retrospectivos , Derivação Portocava Cirúrgica , Anastomose Cirúrgica/métodos , Veia Cava Inferior/cirurgia
9.
Ren Fail ; 44(1): 831-841, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35546431

RESUMO

Kidney transplants (KT) from hepatitis C (HCV) viremic donors to HCV negative recipients has shown promising renal outcomes, however, high incidence of cytomegalovirus (CMV) viremia were reported. We performed a prospective cohort study of 52 HCV negative KT recipients from Methodist University Hospital including 41 receiving transplants from HCV aviremic donors and 11 from HCV viremic donors. CMV specific CD4+ and CD8 + T cell immunity was measured by intracellular flow cytometry assay. Primary outcome was the development of positive CMV specific CD4+ and CD8 + T cell immune response in the entire cohort and each subgroup. The association between donor HCV status and CMV specific CD4+ and CD8 + T cell immune response was analyzed by Cox proportional hazard models. Mean recipient age was 48 ± 13 years, with 73% male and 82% African American. Positive CMV specific CD4+ and CD8 + T cell immune response was found in 53% and 47% of the cohort at 1 month, 65% and 70% at 2 months, 80% and 75% at 4 months, 89% and 87% at 6 months, and 94% and 94% at 9 months post-transplant, respectively. There was no significant difference in the incidence of positive CMV specific T cell immune response between recipients of transplants from HCV aviremic donors compared to HCV viremic donors in unadjusted (for CD8+: HR = 1.169, 95%CI: 0.521-2.623; for CD4+: HR = 1.208, 95%CI: 0.543-2.689) and adjusted (for CD8+: HR = 1.072, 95%CI: 0.458-2.507; for CD4+: HR = 1.210, 95%CI: 0.526-2.784) Cox regression analyses. HCV viremia in donors was not associated with impaired development of CMV specific T cell immunity in this cohort.


Assuntos
Infecções por Citomegalovirus , Hepatite C , Transplante de Rim , Adulto , Antivirais , Infecções por Citomegalovirus/epidemiologia , Feminino , Hepacivirus , Humanos , Imunidade , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Linfócitos T , Doadores de Tecidos , Transplantados , Viremia
10.
Int J Mol Sci ; 23(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36233107

RESUMO

Non-alcoholic fatty liver disease is a huge cause of chronic liver failure around the world. This condition has become more prevalent as rates of metabolic syndrome, type 2 diabetes, and obesity have also escalated. The unfortunate outcome for many people is liver cirrhosis that warrants transplantation or being unable to receive a transplant since many livers are discarded due to high levels of steatosis. Over the past several years, however, a great deal of work has gone into understanding the pathophysiology of this disease as well as possible treatment options. This review summarizes various defatting strategies including in vitro use of pharmacologic agents, machine perfusion of extracted livers, and genomic approaches targeting specific proteins. The goal of the field is to reduce the number of necessary transplants and expand the pool of organs available for use.


Assuntos
Diabetes Mellitus Tipo 2 , Transplante de Fígado , Hepatopatia Gordurosa não Alcoólica , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Perfusão
11.
Int J Mol Sci ; 23(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36361782

RESUMO

Triple negative breast cancer (TNBC) is one of the most aggressive cancers diagnosed amongst women with a high rate of treatment failure and a poor prognosis. Mitochondria have been found to be key players in oncogenesis and tumor progression by mechanisms such as altered metabolism, reactive oxygen species (ROS) production and evasion of apoptosis. Therefore, mitochondrial infusion is an area of interest for cancer treatment. Studies in vitro and in vivo demonstrate mitochondrial-mediated reduction in glycolysis, enhancement of oxidative phosphorylation (OXPHOS), reduction in proliferation, and an enhancement of apoptosis as effective anti-tumor therapies. This review focuses on mitochondrial dysregulation and infusion in malignancies, such as TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Mitocôndrias/metabolismo , Fosforilação Oxidativa , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Carcinogênese/metabolismo , Transformação Celular Neoplásica/metabolismo
12.
Am J Kidney Dis ; 77(5): 739-747.e1, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33333148

RESUMO

RATIONALE & OBJECTIVE: Transplant centers in the United States are increasingly willing to transplant kidneys from hepatitis C virus (HCV)-infected (HCV+) donors into HCV- recipients. We studied the association between donor HCV infection status and kidney allograft function and posttransplantation allograft biopsy findings. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: We examined 65 HCV- recipients who received a kidney from a HCV+ donor and 59 HCV- recipients who received a kidney from a HCV- donor during 2018 at a single transplant center. EXPOSURE: Predictor(s) of donor infection with HCV. OUTCOMES: Kidney allograft function and allograft biopsy findings during the first year following transplantation. ANALYTICAL APPROACH: We compared estimated glomerular filtration rate (eGFR), findings on for-cause and surveillance protocol biopsies, development of de novo donor-specific antibodies (DSAs), and patient and allograft outcomes during the first year following transplantation between recipients of HCV+ and HCV- kidneys. We used linear regression to estimate the independent association between allograft function and HCV viremic status of the kidney donor. RESULTS: The mean age of recipients was 52 ± 11 (SD) years, 43% were female, 19% and 80% of recipients were White and Black, respectively. Baseline characteristics were similar between the HCV+ and HCV- groups. There were no statistically significant differences between the HCV+ and HCV- groups in delayed graft function rates (12% vs 8%, respectively); eGFRs at 3, 6, 9, and 12 months post-transplantation; proportions of patients with cellular rejection (6% vs 7%, respectively); and proportions with antibody-mediated rejection (7% vs 10%, respectively) or de novo DSAs (31% vs 20%, respectively). HCV viremic status was not associated with eGFR at 3, 6, 9, or 12 months. LIMITATIONS: Generalizability from a single-center study and small sample size was limited. CONCLUSIONS: Recipients of kidneys from donors infected with HCV had similar kidney allograft function and probability of rejection in the first year after transplantation compared to those who received kidneys from donors without HCV infection.


Assuntos
Função Retardada do Enxerto/epidemiologia , Taxa de Filtração Glomerular , Rejeição de Enxerto/epidemiologia , Hepatite C Crônica/transmissão , Falência Renal Crônica/cirurgia , Transplante de Rim , Adulto , Aloenxertos/patologia , Anticorpos/imunologia , Antivirais/uso terapêutico , Estudos de Coortes , Feminino , Rejeição de Enxerto/prevenção & controle , Hepatite C Crônica/tratamento farmacológico , Humanos , Imunossupressores/uso terapêutico , Modelos Lineares , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Estudos Retrospectivos , Doadores de Tecidos
13.
Clin Transplant ; 35(12): e14485, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34523744

RESUMO

Kidney transplantation (KT) from hepatitis C virus infected (HCV+) donors to HCV negative recipients achieve excellent graft function but have relatively higher rates of post-KT co-infections presumably due to prolonged HCV viremia in transmission-and-treat approach. Ezetimibe acts as an antagonist of Niemann-Pick C1-Like 1 receptor required for HCV entry and theoretically can reduce HCV viremia. However, no data is available to examine the role of ezetimibe as a bridge therapy between KT surgery and direct acting antiviral (DAA) initiation. A retrospective cohort study including 70 HCV+ to HCV negative KT recipients from Methodist University Hospital and Vanderbilt University Medical Center was performed to determine the association between ezetimibe usage and HCV viremia. Twenty patients received ezetimibe daily while 50 patients did not. Primary outcome of study was mean HCV RNA level at 1-2 weeks post-KT and before initiation of DAA. Median (IQR) viral load (VL) in log copies/ml was one log lower in ezetimibe group versus non-ezetimibe group (4.1 [3.7-5.3] vs. 5.1 [4.4-5.5], P = .01), and highest VL was also lower in ezetimibe group (4.2 [3.7-5.4] vs. 5.4 [4.7-5.9], P = .006). We concluded that ezetimibe bridge therapy might be associated with reduction in HCV VL while waiting for DAA initiation in HCV+ to HCV negative KT recipients.


Assuntos
Hepatite C Crônica , Hepatite C , Transplante de Rim , Antivirais/uso terapêutico , Ezetimiba/uso terapêutico , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Humanos , Rim , Transplante de Rim/efeitos adversos , RNA , Estudos Retrospectivos , Doadores de Tecidos , Transplantados
14.
Clin Transplant ; 35(5): e14281, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33690929

RESUMO

BACKGROUND: The virologic and histologic outcomes of a hepatitis C virus (HCV)-infected liver graft into an HCV-negative recipient are not well understood. We aimed to evaluate the sustained virologic response (SVR) rate and the liver histology at 1 year post-Orthotopic liver transplantation (OLT) with an HCV-infected graft. METHODS: A total of 33 patients received the HCV antibody (Ab)+/nucleic acid amplification test (NAT)+ graft. Of these patients, 23 were HCV-negative recipients and 10 were HCV-positive recipients. The 1-year biopsy data were available for 24 patients: 15 patients in HCV-negative group who received an HCV Ab+/NAT+graft and 9 patients in HCV-positive group who received an HCV Ab+/NAT+ graft. Patients with (+) HCV ribonucleic acid (RNA) were started on direct-acting antiviral (DAA) treatment approximately 107 days after OLT using either a Glecaprevir-Pibrentasvir or Sofosbuvir-Velpatasvir or Sofosbuvir-Ledipasvir. RESULTS: All patients (n = 33) were treated with DAA and achieved SVR. The 1-year post-OLT liver biopsies were available in 24 patients: 9 patients had F1 and F2 fibrosis and 17 patients had minimal to moderate inflammation. There was no statistical difference in fibrosis and inflammation between the HCV-negative vs. HCV-positive recipients. All patients who received the NAT+ graft developed viremia and subsequently achieved SVR with treatment. CONCLUSION: At 1 year protocol liver biopsy, patients had inflammation consistent with viral hepatitis despite the successful eradication of HCV.


Assuntos
Hepatite C Crônica , Hepatite C , Transplante de Fígado , Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Humanos , RNA Viral , Resultado do Tratamento
15.
Int J Mol Sci ; 22(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207555

RESUMO

Transplant glomerulopathy develops through multiple mechanisms, including donor-specific antibodies, T cells and innate immunity. This study investigates circulating small RNA profiles in serum samples of kidney transplant recipients with biopsy-proven transplant glomerulopathy. Among total small RNA population, miRNAs were the most abundant species in the serum of kidney transplant patients. In addition, fragments arising from mature tRNA and rRNA were detected. Most of the tRNA fragments were generated from 5' ends of mature tRNA and mainly from two parental tRNAs: tRNA-Gly and tRNA-Glu. Moreover, transplant patients with transplant glomerulopathy displayed a novel tRNA fragments signature. Gene expression analysis from allograft tissues demonstrated changes in canonical pathways related to immune activation such as iCos-iCosL signaling pathway in T helper cells, Th1 and Th2 activation pathway, and dendritic cell maturation. mRNA targets of down-regulated miRNAs such as miR-1224-5p, miR-4508, miR-320, miR-378a from serum were globally upregulated in tissue. Integration of serum miRNA profiles with tissue gene expression showed that changes in serum miRNAs support the role of T-cell mediated mechanisms in ongoing allograft injury.


Assuntos
Ácidos Nucleicos Livres/sangue , Rejeição de Enxerto/sangue , Nefropatias/sangue , Transplante de Rim , MicroRNAs/sangue , RNA de Transferência de Glicina/sangue , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Células Th1/metabolismo , Células Th2/metabolismo
16.
Int J Mol Sci ; 22(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065421

RESUMO

Dendritic cells (DCs) are unique immune cells that can link innate and adaptive immune responses and Immunometabolism greatly impacts their phenotype. Rapamycin is a macrolide compound that has immunosuppressant functions and is used to prevent graft loss in kidney transplantation. The current study evaluated the therapeutic potential of ex-vivo rapamycin treated DCs to protect kidneys in a mouse model of acute kidney injury (AKI). For the rapamycin single (S) treatment (Rapa-S-DC), Veh-DCs were treated with rapamycin (10 ng/mL) for 1 h before LPS. In contrast, rapamycin multiple (M) treatment (Rapa-M-DC) were exposed to 3 treatments over 7 days. Only multiple ex-vivo rapamycin treatments of DCs induced a persistent reprogramming of mitochondrial metabolism. These DCs had 18-fold more mitochondria, had almost 4-fold higher oxygen consumption rates, and produced more ATP compared to Veh-DCs (Veh treated control DCs). Pathway analysis showed IL10 signaling as a major contributing pathway to the altered immunophenotype after Rapamycin treatment compared to vehicle with significantly lower cytokines Tnfa, Il1b, and Il6, while regulators of mitochondrial content Pgc1a, Tfam, and Ho1 remained elevated. Critically, adoptive transfer of rapamycin-treated DCs to WT recipients 24 h before bilateral kidney ischemia significantly protected the kidneys from injury with a significant 3-fold improvement in kidney function. Last, the infusion of DCs containing higher mitochondria numbers (treated ex-vivo with healthy isolated mitochondria (10 µg/mL) one day before) also partially protected the kidneys from IRI. These studies demonstrate that pre-emptive infusion of ex-vivo reprogrammed DCs that have higher mitochondria content has therapeutic capacity to induce an anti-inflammatory regulatory phenotype to protect kidneys from injury.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Células Dendríticas/efeitos dos fármacos , Isquemia/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Sirolimo/farmacologia , Injúria Renal Aguda/metabolismo , Transferência Adotiva/métodos , Animais , Citocinas/metabolismo , Células Dendríticas/metabolismo , Células HEK293 , Humanos , Inflamação/metabolismo , Isquemia/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/efeitos dos fármacos
17.
Curr Opin Organ Transplant ; 26(1): 23-29, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33315767

RESUMO

PURPOSE OF REVIEW: To summarize recently developed next generation sequencing-based methods to study epigenomics and epitranscriptomics. To elucidate the potential applications of these recently developed methods in transplantation research. RECENT FINDINGS: There are several methods established with the collaborative efforts from different consortiums, such as ENCODE, Human Cell Atlas, and exRNA consortium to study role of epigenetics in human health. Rapid development in the sequencing technology also enabled the establishment of these genome-wide studies. This review specifically focuses on these techniques, such as EM-seq to study DNA methylation, CUT&RUN, and CUT&Tag to study histone/transcription factor--DNA interactions, ATAC-seq to study chromatin accessibility, Hi-C to explore 3D genome architecture and several methods to study epigenetics at single-cell level. In addition, we briefly mentioned recent efforts to study lncRNAs and extracellular miRNAs. SUMMARY: Technical advancements in genomics, particularly epigenomics, shed light on the role of epigenetics and recently epitranscriptomics in different fields. Application of those techniques to transplantation research is still very limited because of technical limitations. On the other hand, there are a lot of promising studies showing that these new techniques can be adapted to study the molecular biology of transplant-related problems.


Assuntos
Epigenômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/metabolismo , Transplante de Órgãos , Cromatina , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos
18.
Am J Transplant ; 20(12): 3285-3293, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32484284

RESUMO

In transplantation, the ever-increasing number of an organ's demand and long-term graft dysfunction constitute some of the major problems. Therefore, alternative solutions to increase the quantity and quality of the organ supply for transplantation are desired. On this subject, revolutionary Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology holds enormous potential for the scientific community with its expanding toolbox. In this minireview, we summarize the history and mechanism of CRISPR/Cas9 systems and explore its potential applications in cellular- and organ-level transplantation. The last part of this review includes future opportunities as well as the challenges in the transplantation field.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Transplante de Órgãos
19.
Am J Transplant ; 20(11): 3061-3071, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32844546

RESUMO

National data on patient characteristics, treatment, and outcomes of critically ill coronavirus disease 2019 (COVID-19) solid organ transplant (SOT) patients are limited. We analyzed data from a multicenter cohort study of adults with laboratory-confirmed COVID-19 admitted to intensive care units (ICUs) at 68 hospitals across the United States from March 4 to May 8, 2020. From 4153 patients, we created a propensity score matched cohort of 386 patients, including 98 SOT patients and 288 non-SOT patients. We used a binomial generalized linear model (log-binomial model) to examine the association of SOT status with death and other clinical outcomes. Among the 386 patients, the median age was 60 years, 72% were male, and 41% were black. Death within 28 days of ICU admission was similar in SOT and non-SOT patients (40% and 43%, respectively; relative risk [RR] 0.92; 95% confidence interval [CI]: 0.70-1.22). Other outcomes and requirement for organ support including receipt of mechanical ventilation, development of acute respiratory distress syndrome, and receipt of vasopressors were also similar between groups. There was a trend toward higher risk of acute kidney injury requiring renal replacement therapy in SOT vs. non-SOT patients (37% vs. 27%; RR [95% CI]: 1.34 [0.97-1.85]). Death and organ support requirement were similar between SOT and non-SOT critically ill patients with COVID-19.


Assuntos
COVID-19/epidemiologia , Estado Terminal/terapia , Hospitalização/tendências , Unidades de Terapia Intensiva/estatística & dados numéricos , Transplante de Órgãos , Pandemias , SARS-CoV-2 , Idoso , Comorbidade , Estado Terminal/epidemiologia , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia
20.
Clin Transplant ; 34(9): e14003, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32506677

RESUMO

BACKGROUND: Alcohol-associated liver disease (AALD) is a rapidly growing indication for liver transplantation (LT). We aimed to examine various clinical, demographic, and behavioral factors to predict post-LT alcohol relapse and graft survival. METHODS: Retrospective analysis was performed on 241 LT recipients with AALD as either a primary or secondary indication for LT (2006-2015). RESULTS: Patients with <6 months of alcohol abstinence had significantly increased cumulative incidence for alcohol relapse compared to those with >6 months of abstinence (P = .0041, Log-Rank). We identified four variables to predict harmful alcohol relapse post-LT: age at LT, non-alcohol-related criminal history, pre-LT abstinence period (Ref >6 months of alcohol abstinence), and drinks per day (Ref <10 drinks/day). Area under the curve (AUC) for the final model was 0.79 (95% CI: 0.68-0.91). Our multivariable model was evaluated with internal cross-validation; random sampling of the study subjects 100 times yielded a median C statistic of 75 (±SD 0.097) and accuracy of 91 (±SD 0.026). The four-variable model served to form the harmful alcohol use post-LT (HALT) score. Graft survival remained significantly lower in patients with <6 months of pre-LT alcohol abstinence and those with blue-collar jobs. CONCLUSION: The HALT score identifies LT candidates with AALD at significant risk for alcohol relapse, potentially guiding transplant centers for pre- and post-LT interventions for improved patient outcomes.


Assuntos
Hepatopatias Alcoólicas , Transplante de Fígado , Abstinência de Álcool , Humanos , Hepatopatias Alcoólicas/etiologia , Hepatopatias Alcoólicas/cirurgia , Recidiva , Estudos Retrospectivos , Fatores de Risco
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