RESUMEN
OBJECTIVE: We sought to investigate the biological effects of pre-reperfusion treatments of the liver after warm and cold ischemic injuries in a porcine donation after circulatory death model. SUMMARY OF BACKGROUND DATA: Donation after circulatory death represents a severe form of liver ischemia and reperfusion injury that has a profound impact on graft function after liver transplantation. METHODS: Twenty donor pig livers underwent 60 minutes of in situ warm ischemia after circulatory arrest and 120 minutes of cold static preservation prior to simulated transplantation using an ex vivo perfusion machine. Four reperfusion treatments were compared: Control-Normothermic (N), Control- Subnormothermic (S), regulated hepatic reperfusion (RHR)-N, and RHR-S (n = 5 each). The biochemical, metabolic, and transcriptomic profiles, as well as mitochondrial function were analyzed. RESULTS: Compared to the other groups, RHR-S treated group showed significantly lower post-reperfusion aspartate aminotransferase levels in the reperfusion effluent and histologic findings of hepatocyte viability and lesser degree of congestion and necrosis. RHR-S resulted in a significantly higher mitochondrial respiratory control index and calcium retention capacity. Transcriptomic profile analysis showed that treatment with RHR-S activated cell survival and viability, cellular homeostasis as well as other biological functions involved in tissue repair such as cytoskeleton or cytoplasm organization, cell migration, transcription, and microtubule dynamics. Furthermore, RHR-S inhibited organismal death, morbidity and mortality, necrosis, and apoptosis. CONCLUSION: Subnormothermic RHR mitigates IRI and preserves hepatic mitochondrial function after warm and cold hepatic ischemia. This organ resuscitative therapy may also trigger the activation of protective genes against IRI. Sub- normothermic RHR has potential applicability to clinical liver transplantation.
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Preservación de Órganos , Transcriptoma , Porcinos , Animales , Preservación de Órganos/métodos , Hígado/patología , Reperfusión , Isquemia , Necrosis/metabolismo , Necrosis/patologíaRESUMEN
Quantitative measurement of the degree of hepatic ischemia-reperfusion injury (IRI) is crucial for developing therapeutic strategies for its treatment. We hypothesized that clearance of fluorescent dye through bile metabolism may reflect the degree of hepatic IRI. In this study, we investigated sodium fluorescein clearance kinetics in blood and bile for quantifying the degree of hepatic IRI. Warm ischemia times (WITs) of 0, 30, or 60 min followed by 1 h or 4 h of reperfusion, were applied to the median and lateral lobes of the liver in Sprague-Dawley rats. Subsequently, 2 mg/kg of sodium fluorescein was injected intravenously, and blood and bile samples were collected over 60 min to measure fluorescence intensities. The bile-to-plasma fluorescence ratios demonstrated an inverse correlation with WIT and were distinctly lower in the 60-min WIT group than in the control or 30-min WIT groups. Bile-to-plasma fluorescence ratios displayed superior discriminability for short versus long WITs when measured 1 h after reperfusion versus 4 h. We conclude that the bile-to-blood ratio of fluorescence after sodium fluorescein injection has the potential to enable the quantification of hepatic IRI severity.NEW & NOTEWORTHY Previous attempts to use fluorophore clearance to test liver function have relied on a single source of data. However, the kinetics of substrate processing via bile metabolism include decreasing levels in blood and increasing levels in bile. Thus, we analyzed data from blood and bile to better reflect fluorescein clearance kinetics.
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Bilis , Daño por Reperfusión , Animales , Bilis/metabolismo , Fluoresceína/metabolismo , Fluoresceína/uso terapéutico , Cinética , Hígado/metabolismo , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/metabolismoRESUMEN
BACKGROUND AND AIMS: The Organ Procurement and Transplantation Network recently approved liver transplant (LT) prioritization for patients with hepatocellular carcinoma (HCC) beyond Milan Criteria (MC) who are down-staged (DS) with locoregional therapy (LRT). We evaluated post-LT outcomes, predictors of down-staging, and the impact of LRT in patients with beyond-MC HCC from the U.S. Multicenter HCC Transplant Consortium (20 centers, 2002-2013). APPROACH AND RESULTS: Clinicopathologic characteristics, overall survival (OS), recurrence-free survival (RFS), and HCC recurrence (HCC-R) were compared between patients within MC (n = 3,570) and beyond MC (n = 789) who were down-staged (DS, n = 465), treated with LRT and not down-staged (LRT-NoDS, n = 242), or untreated (NoLRT-NoDS, n = 82). Five-year post-LT OS and RFS was higher in MC (71.3% and 68.2%) compared with DS (64.3% and 59.5%) and was lowest in NoDS (n = 324; 60.2% and 53.8%; overall P < 0.001). DS patients had superior RFS (60% vs. 54%, P = 0.043) and lower 5-year HCC-R (18% vs. 32%, P < 0.001) compared with NoDS, with further stratification by maximum radiologic tumor diameter (5-year HCC-R of 15.5% in DS/<5 cm and 39.1% in NoDS/>5 cm, P < 0.001). Multivariate predictors of down-staging included alpha-fetoprotein response to LRT, pathologic tumor number and size, and wait time >12 months. LRT-NoDS had greater HCC-R compared with NoLRT-NoDS (34.1% vs. 26.1%, P < 0.001), even after controlling for clinicopathologic variables (hazard ratio [HR] = 2.33, P < 0.001) and inverse probability of treatment-weighted propensity matching (HR = 1.82, P < 0.001). CONCLUSIONS: In LT recipients with HCC presenting beyond MC, successful down-staging is predicted by wait time, alpha-fetoprotein response to LRT, and tumor burden and results in excellent post-LT outcomes, justifying expansion of LT criteria. In LRT-NoDS patients, higher HCC-R compared with NoLRT-NoDS cannot be explained by clinicopathologic differences, suggesting a potentially aggravating role of LRT in patients with poor tumor biology that warrants further investigation.
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Técnicas de Ablación/métodos , Carcinoma Hepatocelular/terapia , Enfermedad Hepática en Estado Terminal/terapia , Neoplasias Hepáticas/terapia , Trasplante de Hígado/estadística & datos numéricos , Recurrencia Local de Neoplasia/epidemiología , Técnicas de Ablación/estadística & datos numéricos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Supervivencia sin Enfermedad , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/mortalidad , Enfermedad Hepática en Estado Terminal/patología , Femenino , Estudios de Seguimiento , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Hígado/efectos de la radiación , Hígado/cirugía , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Trasplante de Hígado/normas , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante/métodos , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Radioterapia Adyuvante/métodos , Radioterapia Adyuvante/estadística & datos numéricos , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Obtención de Tejidos y Órganos/normas , Carga Tumoral/efectos de la radiación , Estados Unidos/epidemiología , Listas de Espera/mortalidadRESUMEN
We describe the challenging perioperative course of a 55-year-old patient with hepatic failure requiring liver transplantation (LT). Different modalities of the extracorporeal device were successfully used, ranging from veno-veno bypass to partial and full veno-veno extracorporeal membrane oxygenation (ECMO) in order to optimize preload, reduce bleeding from the collateral circulation, optimize acid base balance and/or improve oxygenation. The case highlights the potential use of the device as a rescue method in challenging cases. Furthermore this is the first documented case that extracorporeal CO2 removal (ECCO2R) is used to optimize the biochemistry profile intraoperatively during a LT. The patient was weaned off the device at the end of the case and has been discharged home.
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Oxigenación por Membrana Extracorpórea , Trasplante de Hígado , Humanos , Persona de Mediana EdadRESUMEN
OBJECTIVE: The aim of the study was to determine the rate, predictors, and impact of complete pathologic response (cPR) to pretransplant locoregional therapy (LRT) in a large, multicenter cohort of hepatocellular carcinoma (HCC) patients undergoing liver transplantation (LT). BACKGROUND: LRT is used to mitigate waitlist dropout for patients with HCC awaiting LT. Degree of tumor necrosis found on explant has been associated with recurrence and overall survival, but has not been evaluated in a large, multicenter study. METHODS: Comparisons were made among patients receiving pre-LT LRT with (n = 802) and without (n = 2637) cPR from the United States Multicenter HCC Transplant Consortium (UMHTC), and multivariable predictors of cPR were identified using logistic regression. RESULTS: Of 3439 patients, 802 (23%) had cPR on explant. Compared with patients without cPR, cPR patients were younger; had lower Model for End-stage Liver Disease (MELD) scores, AFP levels, and neutrophil-lymphocyte ratios (NLR); were more likely to have tumors within Milan criteria and fewer LRT treatments; and had significantly lower 1-, 3-, and 5-year incidence of post-LT recurrence (1.3%, 3.5%, and 5.2% vs 6.2%, 13.5%, and 16.4%; P < 0.001) and superior overall survival (92%, 84%, and 75% vs 90%, 78%, and 68%; P < 0.001). Multivariable predictors of cPR included age, sex, liver disease diagnosis, MELD, AFP, NLR, radiographic Milan status, and number of LRT treatments (C-statistic 0.67). CONCLUSIONS: For LT recipients with HCC receiving pretransplant LRT, achieving cPR portends significantly lower posttransplant recurrence and superior survival. Factors predicting cPR are identified, which may help prioritize patients and guide LRT strategies to optimize posttransplant cancer outcomes.
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Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/terapia , Trasplante de Hígado , Carcinoma Hepatocelular/cirugía , Progresión de la Enfermedad , Femenino , Humanos , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Recurrencia Local de Neoplasia , Medición de Riesgo , Factores de Riesgo , Análisis de Supervivencia , Factores de Tiempo , Carga Tumoral , Estados UnidosRESUMEN
BACKGROUND: Patients undergoing liver transplantation (LT) frequently receive platelet transfusion (PLT) to minimize their risk of hemorrhage. Alloimmunization to platelets may lead to refractoriness to PLT. Data on the implications of platelet alloimmunization in patients undergoing LT remain limited. We examined the effect of human leukocyte antigen class I (HLA-I) antibodies on PLT refractoriness and short-term outcomes after LT. METHODS: Peritransplant clinical and PLT factors were reviewed for all adult liver or simultaneous liver-kidney transplantations from 2012 to 2017. Sensitized patients (SE) with pretransplant HLA-I calculated panel-reactive antibody ≥20% were compared with unsensitized patients (US) with calculated panel-reactive antibody <20%. The mean follow-up was 21.4 mo. RESULTS: Alloimmunization was observed in 39% of the study cohort. SE (n = 28) received 272 PLTs, and US (n = 44) received 246 PLTs. History of pregnancy was higher among SE than US (P < 0.01); otherwise, both groups had similar clinical characteristics. SE had higher rates of PLT refractoriness (66% versus 47%; P < 0.01) than US. The mean platelet corrected count increment was lower among SE compared with US up to 100 min after PLT (P < 0.05). Alloimmunization and simultaneous liver-kidney transplantation independently predicted refractoriness on multivariate logistic regression (P < 0.05). Early allograft rejection and patient survival rates were comparable for both groups. CONCLUSIONS: LT patients experienced high rates of HLA-I alloimmunization and PLT refractoriness. SE had higher rates of refractoriness and lower mean corrected count increment after transfusion compared with US. Our study suggests that further research to evaluate the utility of HLA-matched PLTs in HLA-I alloimmunized LT patients is warranted.
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Antígenos HLA/inmunología , Isoanticuerpos/inmunología , Trasplante de Hígado/efectos adversos , Transfusión de Plaquetas/efectos adversos , Trombocitopenia/terapia , Pérdida de Sangre Quirúrgica/prevención & control , Enfermedad Hepática en Estado Terminal/sangre , Enfermedad Hepática en Estado Terminal/complicaciones , Enfermedad Hepática en Estado Terminal/cirugía , Femenino , Antígenos HLA/sangre , Prueba de Histocompatibilidad , Humanos , Isoanticuerpos/sangre , Masculino , Persona de Mediana Edad , Hemorragia Posoperatoria/etiología , Hemorragia Posoperatoria/prevención & control , Estudios Prospectivos , Estudios Retrospectivos , Trombocitopenia/sangre , Trombocitopenia/etiología , Resultado del TratamientoRESUMEN
BACKGROUND: Orthotopic liver transplantation (OLT) after neoadjuvant therapy (NT) in well-selected patients with unresectable hilar cholangiocarcinoma (CCA) achieves excellent recurrence-free survival. Current criteria for NT-OLT exclude patients with locally advanced hilar and intrahepatic CCA from potential cure. We sought to evaluate the efficacy of NT in downstaging locally advanced CCA, and examine outcomes after OLT. METHODS: Among 24 patients referred for unresectable hilar and intrahepatic CCA from January 2013 through August 2017, 18 met center-specific inclusion criteria for the NT-OLT treatment protocol: hilar tumor size ≤3.5 cm or intrahepatic ≤8 cm, and regional lymphadenopathy but without distant metastasis. Median follow-up was 22.1 mo from diagnosis. RESULTS: Of 18 patients who initiated NT, 11 were removed from the protocol due to tumor progression (n = 6) or uncontrolled infection and failure-to-thrive (n = 5). Median NT duration tended to be shorter for patients progressing to dropout than for those surviving to OLT (5.5 versus 13.5 mo, P = 0.109). Among five patients who received OLT, 1-y post-OLT patient survival was 80%: three survive recurrence-free (14.5-29.2 mo post-OLT); one developed an isolated tumor recurrence in a single portacaval lymph node at 12 mo post-OLT; and one experienced non-tumor-related death. All dropout patients died at a median of 14.4 mo after diagnosis. CONCLUSIONS: This is the first prospective study to show successful NT downstaging of unresectable locally advanced hilar and intrahepatic CCA before OLT. NT-OLT for select patients with locally advanced hilar and intrahepatic CCA achieved acceptable short-term recurrence-free survival.
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Neoplasias de los Conductos Biliares/terapia , Conductos Biliares Intrahepáticos , Quimioradioterapia Adyuvante , Colangiocarcinoma/terapia , Trasplante de Hígado , Terapia Neoadyuvante , Adulto , Anciano , Neoplasias de los Conductos Biliares/mortalidad , Neoplasias de los Conductos Biliares/patología , Colangiocarcinoma/mortalidad , Colangiocarcinoma/patología , Neoplasias del Conducto Colédoco/mortalidad , Neoplasias del Conducto Colédoco/patología , Neoplasias del Conducto Colédoco/terapia , Femenino , Estudios de Seguimiento , Humanos , Tumor de Klatskin/mortalidad , Tumor de Klatskin/patología , Tumor de Klatskin/terapia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Proyectos Piloto , Estudios Prospectivos , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
BACKGROUND: The effect of hepatic ischemia-reperfusion injury (IRI) on bile transporter (BT) gene expression is unknown. We hypothesized that abnormal expression of BTs during hepatic IRI is dependent on nuclear factor erythroid 2-related factor 2 (NRF2), which contributes to the cholestasis after reperfusion. METHODS: Sham surgery and short (60 min) or long (90 min) periods of warm ischemia time (WIT) with or without reperfusion for 24 h were applied to wild-type Sprague-Dawley rats and Nrf2 knockout rats (n = 5 per group). At each stage of IRI, the serum levels of aminotransferase, total bilirubin, and bile acids were measured. In addition, hepatic tissue was sampled to determine the histologic score of IRI (Suzuki score), measure adenosine triphosphate (ATP), and identify the quantitative real-time polymerase chain reactions of BTs (Oatp1, Ntcp, Mrp2, Bsep, and Mrp3). RESULTS: In short periods of WIT, BT expression increased during the ischemia stage and returned to the baseline after reperfusion. However, in long periods of WIT, BT expression did not increase after ischemia and decreased further after reperfusion. Short WIT did not increase BT expression in Nrf2 knockout animals. The level of BT expression was correlated with the Suzuki score, the serum levels of aminotransferase, bilirubin, and bile acids, and tissue ATP level. Stepwise multiple regression analysis derived equations to predict the Suzuki score (R2 = 76.8, P < 0.001), serum total bilirubin (R2 = 61.2, P < 0.001), and tissue ATP (R2 = 61.1, P < 0.001). CONCLUSIONS: Short WIT induces the transcriptional activities of BT, whereas long WIT depresses them, and the effect was blunted by Nrf2 knockout status. BT expression can be considered a surrogate marker for hepatic IRI.
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Bilis/metabolismo , Hígado/irrigación sanguínea , Proteínas de Transporte de Membrana/genética , Factor 2 Relacionado con NF-E2/fisiología , Daño por Reperfusión/metabolismo , Animales , Masculino , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Transcripción Genética , Isquemia TibiaRESUMEN
: For patients with hepatoblastoma, a timely and complete resection of the tumor is critical to the patient's tumor recurrence-free survival. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), a 2-stage hepatectomy procedure, has revolutionized the surgical management of large hepatic tumors with insufficient future liver remnant (FLR) at presentation. Although existing data support the utility of ALPPS in adults with primary and metastatic hepatobiliary malignancy, the literature in children is scarce. To our knowledge, this is the first report showing clinical applicability and safety of the modified ALPPS procedure in a small infant (54 days old) with hepatoblastoma who presented with insufficient FLR. Our report suggests the modified ALPPS could potentially expand the surgical treatment alternative for small infants with large hepatoblastoma.
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Hepatectomía/métodos , Hepatoblastoma/cirugía , Neoplasias Hepáticas/cirugía , Vena Porta/cirugía , Humanos , Lactante , Recién Nacido , Ligadura/métodos , Masculino , Resultado del TratamientoRESUMEN
OBJECTIVE: To evaluate the effect of pretransplant bridging locoregional therapy (LRT) on hepatocellular carcinoma (HCC) recurrence and survival after liver transplantation (LT) in patients meeting Milan criteria (MC). SUMMARY BACKGROUND DATA: Pre-LT LRT mitigates tumor progression and waitlist dropout in HCC patients within MC, but data on its impact on post-LT recurrence and survival remain limited. METHODS: Recurrence-free survival and post-LT recurrence were compared among 3601 MC patients with and without bridging LRT utilizing competing risk Cox regression in consecutive patients from 20 US centers (2002-2013). RESULTS: Compared with 747 LT recipients not receiving LRT, 2854 receiving LRT had similar 1, 3, and 5-year recurrence-free survival (89%, 77%, 68% vs 85%, 75%, 68%; P = 0.490) and 5-year post-LT recurrence (11.2% vs 10.1%; P = 0.474). Increasing LRT number [3 LRTs: hazard ratio (HR) 2.1, P < 0.001; 4+ LRTs: HR 2.5, P < 0.001), and unfavorable waitlist alphafetoprotein trend significantly predicted post-LT recurrence, whereas LRT modality did not. Treated patients achieving complete pathologic response (cPR) had superior 5-year RFS (72%) and lower post-LT recurrence (HR 0.52, P < 0.001) compared with both untreated patients (69%; P = 0.010; HR 1.0) and treated patients not achieving cPR (67%; P = 0.010; HR 1.31, P = 0.039), who demonstrated increased recurrence compared with untreated patients in multivariate analysis controlling for pretransplant and pathologic factors (HR 1.32, P = 0.044). CONCLUSIONS: Bridging LRT in HCC patients within MC does not improve post-LT survival or HCC recurrence in the majority of patients who fail to achieve cPR. The need for increasing LRT treatments and lack of alphafetoprotein response to LRT independently predict post-LT recurrence, serving as a surrogate for underlying tumor biology which can be utilized for prioritization of HCC LT candidates.
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Técnicas de Ablación , Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/cirugía , Trasplante de Hígado , Recurrencia Local de Neoplasia/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/mortalidad , Terapia Combinada , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Adulto JovenRESUMEN
Living donor liver transplantation (LDLT) is a technically demanding endeavor, requiring command of the complex anatomy of partial liver grafts. We examined the influence of anatomic variation and reconstruction techniques on surgical outcomes and graft survival in the 9-center Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL). Data from 272 adult LDLT recipients (2011-2015) included details on anatomic characteristics and types of intraoperative biliary reconstruction. Associations were tested between reconstruction technique and complications, which included first biliary complication (BC; leak, stricture, or biloma) and first vascular complication (VC; hepatic artery thrombosis [HAT] or portal vein thrombosis [PVT]). Time to patient death, graft failure, and complications were estimated using Kaplan-Meier curves and tested with log-rank tests. Median posttransplant follow-up was 1.2 years. Associations were found between the type of biliary reconstruction and the incidence of VC (P = 0.03) and BC (P = 0.05). Recipients with Roux-en-Y hepaticojejunostomy had the highest probability of VC. Recipients with biliary reconstruction involving the use of high biliary radicals on the recipient duct had the highest likelihood of developing BC (56% by 1 year) compared with duct-to-duct (42% by 1 year). In conclusion, the varied surgical approaches in the A2ALL centers offer a novel opportunity to compare disparate LDLT approaches. The choice to use higher biliary radicals on the recipient duct for reconstruction was associated with more BC, possibly secondary to devascularization and ischemia. The use of Roux-en-Y biliary reconstruction was associated with VCs (HAT and PVT). These results can be used to guide biliary reconstruction decisions in the setting of anatomic variants and inform further improvements in LDLT reconstructions. Ultimately, this information may contribute to a lower incidence of technical complications after LDLT. Liver Transplantation 23 1519-1530 2017 AASLD.
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Enfermedades de los Conductos Biliares/epidemiología , Conductos Biliares/anatomía & histología , Procedimientos Quirúrgicos del Sistema Biliar/métodos , Enfermedad Hepática en Estado Terminal/cirugía , Trasplante de Hígado/efectos adversos , Procedimientos de Cirugía Plástica/métodos , Complicaciones Posoperatorias/epidemiología , Adulto , Anciano , Anastomosis en-Y de Roux/efectos adversos , Anastomosis en-Y de Roux/métodos , Variación Anatómica , Enfermedades de los Conductos Biliares/etiología , Conductos Biliares/patología , Conductos Biliares/cirugía , Procedimientos Quirúrgicos del Sistema Biliar/efectos adversos , Estudios de Cohortes , Constricción Patológica/epidemiología , Constricción Patológica/etiología , Femenino , Supervivencia de Injerto , Humanos , Incidencia , Hígado/irrigación sanguínea , Hígado/cirugía , Trasplante de Hígado/métodos , Trasplante de Hígado/estadística & datos numéricos , Donadores Vivos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Procedimientos de Cirugía Plástica/efectos adversos , Trombosis/epidemiología , Trombosis/etiología , Resultado del Tratamiento , Estados Unidos/epidemiologíaRESUMEN
The long-term impact of allosensitization between ABO compatible donor/recipient pairs in liver transplantation is unclear. Accumulating clinical evidence suggests that donor-specific antibody formation may lead to antibody-mediated rejection and is causally linked to pathologic injury, graft loss, and death. Although this immune-mediated graft dysfunction is increasingly being associated with poor outcomes, the specific pathologic sequelae are not defined. Herein, we examine the relationship between allosensitization, antibody-mediated rejection, and subsequent graft pathology.
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Sistema del Grupo Sanguíneo ABO/inmunología , Rechazo de Injerto/inmunología , Isoanticuerpos/inmunología , Trasplante de Hígado , Hígado/patología , Rechazo de Injerto/patología , Humanos , Hígado/inmunologíaRESUMEN
Ischemia and reperfusion significantly contributes to the morbidity and mortality of liver surgery and transplantation. Based on studies showing a critical role for adenosine signaling in mediating tissue adaptation during hypoxia, we hypothesized that signaling events through adenosine receptors (ADORA1, ADORA2A, ADORA2B, or ADORA3) attenuates hepatic ischemia and reperfusion injury. Initial screening studies of human liver biopsies obtained during hepatic transplantation demonstrated a selective and robust induction of ADORA2B transcript and protein following ischemia and reperfusion. Subsequent exposure of gene-targeted mice for each individual adenosine receptor to liver ischemia and reperfusion revealed a selective role for the Adora2b in liver protection. Moreover, treatment of wild-type mice with an Adora2b-selective antagonist resulted in enhanced liver injury, whereas Adora2b-agonist treatment was associated with attenuated hepatic injury in wild-type, but not in Adora2b(-/-) mice. Subsequent studies in mice with Adora2b deletion in different tissues--including vascular endothelia, myeloid cells, and hepatocytes--revealed a surprising role for hepatocellular-specific Adora2b signaling in attenuating nuclear factor NF-κB activation and thereby mediating liver protection from ischemia and reperfusion injury. These studies provide a unique role for hepatocellular-specific Adora2b signaling in liver protection during ischemia and reperfusion injury.
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Hígado/fisiopatología , Receptor de Adenosina A2B/metabolismo , Daño por Reperfusión/fisiopatología , Transducción de Señal/fisiología , Animales , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Perfilación de la Expresión Génica , Humanos , Immunoblotting , Hígado/metabolismo , Ratones , Ratones Noqueados , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Receptor de Adenosina A2B/genética , Daño por Reperfusión/metabolismoRESUMEN
PURPOSE OF REVIEW: Owing to a severe shortage of organs for patients with end-stage diseases, novel techniques in organ preservation and perfusion need to be studied and reviewed to increase the number of available organs for transplant. Many patients will die while waiting for an organ. To make organs from extended-criteria donors feasible, optimal conditions for pulsatile perfusion and the potential for organ reconditioning at implantation need to be addressed. RECENT FINDINGS: Many techniques in organ preservation and perfusion are being studied. Several laboratories are studying the effects of temperature for organ perfusion. Two areas being studied are hypothermic and normothermic machine perfusion. In the area of organ preservation, new solutions are being studied such as a substrate-enriched, oxygen-saturated, and leukocyte-depleted perfusate to help with organ quality. SUMMARY: Even with the strides being made in organ preservation and perfusion, there are still many unanswered questions. More studies will need to be done to find the optimal conditions for duration of perfusion in the cold phase, optimal perfusion solution, degree of oxygenation, and the addition of pharmacologic agents, to improve organ function and expand the organ pool.
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Soluciones Preservantes de Órganos/farmacología , Preservación de Órganos/métodos , HumanosRESUMEN
PURPOSE OF REVIEW: This article reviews current strategies for living-donor organ procurement in liver, kidney, pancreas, and intestinal transplant. RECENT FINDINGS: Here we summarize current open and laparoscopic approaches to living donation of abdominal organs. SUMMARY: Living donation strategies expand the organ pool in the setting of a significant organ shortage.
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Hígado/cirugía , Obtención de Tejidos y Órganos , Paro Cardíaco , Humanos , Donadores Vivos/provisión & distribución , Trasplante de Órganos , Obtención de Tejidos y Órganos/normasRESUMEN
UNLABELLED: Ischemia and reperfusion-elicited tissue injury contributes to morbidity and mortality of hepatic surgery and during liver transplantation. Previous studies implicated extracellular adenosine signaling in liver protection. Based on the notion that extracellular adenosine signaling is terminated by uptake from the extracellular towards the intracellular compartment by way of equilibrative nucleoside transporters (ENTs), we hypothesized a functional role of ENTs in liver protection from ischemia. During orthotopic liver transplantation in humans, we observed higher expressional levels of ENT1 than ENT2, in conjunction with repression of ENT1 and ENT2 transcript and protein levels following warm ischemia and reperfusion. Treatment with the pharmacologic ENT inhibitor dipyridamole revealed elevations of hepatic adenosine levels and robust liver protection in a murine model of liver ischemia and reperfusion. Studies in gene-targeted mice for Ent1 or Ent2 demonstrated selective protection from liver injury in Ent1(-/-) mice. Treatment with selective adenosine receptor antagonists indicated a contribution of Adora2b receptor signaling in ENT-dependent liver protection. CONCLUSION: These findings implicate ENT1 in liver protection from ischemia and reperfusion injury and suggest ENT inhibitors may be of benefit in the prevention or treatment of ischemic liver injury.
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Adenosina/fisiología , Tranportador Equilibrativo 1 de Nucleósido/fisiología , Hígado/irrigación sanguínea , Daño por Reperfusión/prevención & control , Animales , Dipiridamol/farmacología , Transportador Equilibrativo 2 de Nucleósido/fisiología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/fisiología , Trasplante de Hígado , Ratones , Ratones Endogámicos C57BL , Receptor de Adenosina A2B/fisiologíaRESUMEN
Orthotopic liver transplantation remains the definitive treatment for patients with end-stage liver disease. Unfortunately, the increasing demand for donor livers and the limited supply of viable organs have both led to a critical need for innovative strategies to expand the pool of transplantable organs. The mitochondrion, central to hepatic cellular function, plays a pivotal role in hepatic ischemic injury, with impaired mitochondrial function and oxidative stress leading to cell death. Mitochondrial protection strategies have shown promise in mitigating IRI and resuscitating marginal organs for transplant. Machine perfusion (MP) has been proven a valuable tool for reviving marginal organs with very promising results. Evaluation of liver viability during perfusion traditionally relies on parameters including lactate clearance, bile production, and transaminase levels. Nevertheless, the quest for more comprehensive and universally applicable viability markers persists. Normothermic regional perfusion has gained robust attention, offering extended recovery time for organs from donation after cardiac death donors. This approach has shown remarkable success in improving organ quality and reducing ischemic injury using the body's physiological conditions. The current challenge lies in the absence of a reliable assessment tool for predicting graft viability and post-transplant outcomes. To address this, exploring insights from mitochondrial function in the context of ischemia-reperfusion injury could offer a promising path toward better patient outcomes and graft longevity. Indeed, hypoxia-induced mitochondrial injury may serve as a surrogate marker of organ viability following oxygenated resuscitation techniques in the future.
Asunto(s)
Preservación de Órganos , Daño por Reperfusión , Humanos , Preservación de Órganos/métodos , Hígado , Daño por Reperfusión/prevención & control , Isquemia , Metabolismo Energético , Mitocondrias , Perfusión/métodosRESUMEN
Ischemia-reperfusion injury (IRI) profoundly impacts organ transplantation, especially in orthotopic liver transplantation (OLT). Disruption of the mitochondrial respiratory chain during ischemia leads to ATP loss and ROS production. Reperfusion exacerbates mitochondrial damage, triggering the release of damage-associated molecular patterns (DAMPs) and inflammatory responses. Mitochondrial dysfunction, a pivotal aspect of IRI, is explored in the context of the regulatory role of ectonucleotidases in purinergic signaling and immune responses. CD39, by hydrolyzing ATP and ADP; and CD73, by converting AMP to adenosine, emerge as key players in mitigating liver IRI, particularly through ischemic preconditioning and adenosine receptor signaling. Despite established roles in vascular health and immunity, the impact of ectonucleotidases on mitochondrial function during hepatic IRI is unclear. This review aims to elucidate the interplay between CD39/73 and mitochondria, emphasizing their potential as therapeutic targets for liver transplantation. This article explores the role of CD39/73 in tissue hypoxia, emphasizing adenosine production during inflammation. CD39 and CD73 upregulation under hypoxic conditions regulate immune responses, demonstrating protective effects in various organ-specific ischemic models. However, prolonged adenosine activation may have dual effects, beneficial in acute settings but detrimental in chronic hypoxia. Herein, we raise questions about ectonucleotidases influencing mitochondrial function during hepatic IRI, drawing parallels with cancer cell responses to chemotherapy. The review underscores the need for comprehensive research into the intricate interplay between ectonucleotidases, mitochondrial dynamics, and their therapeutic implications in hepatic IRI, providing valuable insights for advancing transplantation outcomes.
RESUMEN
Adult recipients of living donor liver transplantation (LDLT) have a higher incidence of biliary complications than recipients of deceased donor liver transplantation (DDLT). Our objective was to define the intensity of the interventions and the time to resolution after the diagnosis of biliary complications after liver transplantation. We analyzed the management and resolution of posttransplant biliary complications and investigated the comparative effectiveness of interventions in LDLT and DDLT recipients. For the analysis of biliary complications (leaks or strictures), we used a retrospective cohort of patients who underwent liver transplantation at 8 centers between 1998 and 2006 (median follow-up from onset=4.7 years). The numbers, procedure types, and times to resolution were compared for LDLT and DDLT recipients. Posttransplant biliary complications occurred in 47 of the 189 DDLT recipients (25%) and in 141 of the 356 LDLT recipients (40%). Biliary leaks constituted 38% of the post-DDLT biliary complications (n=18) and 65% of the post-LDLT biliary complications (n=91). The median times to first biliary complications were similar for DDLT and LDLT (11 versus 14 days for leaks, P=0.63; 69 versus 107 days for strictures, P=0.34). Overall, 1225 diagnostic and therapeutic procedures, including reoperation and retransplantation, were performed (6.5±5.4 per recipient; 5.5±3.6 for DDLT versus 6.8±5.8 for LDLT, P=0.52). The median number of months to the resolution of a biliary complication (i.e., a tube-, stent-, and drain-free status) did not significantly differ between the DDLT and LDLT groups for leaks (2.3 versus 1.3 months, P=0.29) or strictures (4.9 versus 2.3 months, P=0.61). Although the incidence of biliary complications is higher after LDLT versus DDLT, the treatment requirements and the time to resolution after the development of a biliary complication are similar for LDLT and DDLT recipients.