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1.
Clin Transplant ; 38(7): e15391, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38967586

RESUMO

INTRODUCTION: Given the importance of understanding COVID-19-positive donor incidence and acceptance, we characterize chronological and geographic variations in COVID-19 incidence relative to COVID-19-positive donor acceptance. METHODS: Data on deceased donors and recipients of liver and kidney transplants were obtained from the UNOS database between 2020 and 2023. Hierarchical cluster analysis was used to assess trends in COVID-19-positive donor incidence. Posttransplant graft and patient survival were assessed using Kaplan-Meier curves. RESULTS: From among 38 429 deceased donors, 1517 were COVID-19 positive. Fewer kidneys (72.4% vs. 76.5%, p < 0.001) and livers (56.4% vs. 62.0%, p < 0.001) were used from COVID-19-positive donors versus COVID-19-negative donors. Areas characterized by steadily increased COVID-19 donor incidence exhibit the highest transplantation acceptance rates (92.33%), followed by intermediate (84.62%) and rapidly increased (80.00%) COVID-19 incidence areas (p = 0.016). Posttransplant graft and patient survival was comparable among recipients, irrespective of donor COVID-19 status. CONCLUSIONS: Regions experiencing heightened rates of COVID-19-positive donors are associated with decreased acceptance of liver and kidney transplantation. Similar graft and patient survival is noted among recipients, irrespective of donor COVID-19 status. These findings emphasize the need for adaptive practices and unified medical consensus in navigating a dynamic pandemic.


Assuntos
COVID-19 , Sobrevivência de Enxerto , Transplante de Rim , Transplante de Fígado , SARS-CoV-2 , Doadores de Tecidos , Humanos , COVID-19/epidemiologia , Incidência , Masculino , Feminino , Doadores de Tecidos/provisão & distribuição , Doadores de Tecidos/estatística & dados numéricos , Pessoa de Meia-Idade , Adulto , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Idoso , Taxa de Sobrevida , Transplantados/estatística & dados numéricos , Estados Unidos/epidemiologia
2.
Clin Transplant ; 38(4): e15290, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38545890

RESUMO

BACKGROUND: Over the last decade there has been a surge in overdose deaths due to the opioid crisis. We sought to characterize the temporal change in overdose donor (OD) use in liver transplantation (LT), as well as associated post-LT outcomes, relative to the COVID-19 era. METHODS: LT candidates and donors listed between January 2016 and September 2022 were identified from the Scientific Registry of Transplant Recipients database. Trends in LT donors and changes related to OD were assessed pre- versus post-COVID-19 (February 2020). RESULTS: Between 2016 and 2022, most counties in the United States experienced an increase in overdose-related deaths (n = 1284, 92.3%) with many counties (n = 458, 32.9%) having more than a doubling in drug overdose deaths. Concurrently, there was an 11.2% increase in overall donors, including a 41.7% increase in the number of donors who died from drug overdose. In pre-COVID-19 overdose was the 4th top mechanism of donor death, while in the post-COVID-19 era, overdose was the 2nd most common cause of donor death. OD was younger (OD: 35 yrs, IQR 29-43 vs. non-OD: 43 yrs, IQR 31-56), had lower body mass index (≥35 kg/cm2, OD: 31.2% vs. non-OD: 33.5%), and was more likely to be HCV+ (OD: 28.9% vs. non-OD: 5.4%) with lower total bilirubin (≥1.1 mg/dL, OD: 12.9% vs. non-OD: 20.1%) (all p < .001). Receipt of an OD was not associated with worse graft survival (HR .94, 95% CI .88-1.01, p = .09). CONCLUSIONS: Opioid deaths markedly increased following the COVID-19 pandemic, substantially altering the LT donor pool in the United States.


Assuntos
COVID-19 , Overdose de Drogas , Transplante de Fígado , Humanos , Estados Unidos/epidemiologia , Epidemia de Opioides , Pandemias , Doadores de Tecidos , COVID-19/epidemiologia
3.
Am J Transplant ; 23(8): 1227-1240, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37156300

RESUMO

Intracardiac thrombosis and/or pulmonary thromboembolism (ICT/PE) is a rare but devastating complication during liver transplantation. Its pathophysiology remains poorly understood, and successful treatment remains a challenge. This systematic review summarizes the available published clinical data regarding ICT/PE during liver transplantation. Databases were searched for all publications reporting on ICT/PE during liver transplantation. Data collected included its incidence, patient characteristics, the timing of diagnosis, treatment strategies, and patient outcomes. This review included 59 full-text citations. The point prevalence of ICT/PE was 1.42%. Thrombi were most often diagnosed during the neohepatic phase, particularly at allograft reperfusion. Intravenous heparin was effective in preventing early-stage thrombus from progressing further and restoring hemodynamics in 76.32% of patients it was utilized for; however, the addition of tissue plasminogen activator or sole use of tissue plasminogen activator offered diminishing returns. Despite all resuscitation efforts, the in-hospital mortality rate of an intraoperative ICT/PE was 40.42%, with nearly half of these patients dying intraoperatively. The results of our systematic review are an initial step for providing clinicians with data that can help identify higher-risk patients. The clinical implications of our results warrant the development of identification and management strategies for the timely and effective treatment of these tragic occurrences during liver transplantation.


Assuntos
Cardiopatias , Transplante de Fígado , Embolia Pulmonar , Trombose , Humanos , Ativador de Plasminogênio Tecidual , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Trombose/etiologia , Trombose/diagnóstico , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/tratamento farmacológico , Embolia Pulmonar/etiologia
4.
Ann Surg ; 278(2): 230-238, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36994716

RESUMO

OBJECTIVE: We sought to evaluate the impact of liver transplantation (LT) programs on the prognosis of hepatocellular carcinoma (HCC) patients who underwent liver resection (LR) and noncurative intent treatment. BACKGROUND: LT programs have an array of resources and services that would positively affect the prognosis of patients with HCC. METHODS: Patients who underwent LT, LR, radiotherapy (RT), or chemotherapy (CTx) for HCC between 2004 and 2018 were included in the National Cancer Database. Institutions with LT programs were defined as those that performed 1 or more LT for at least 5 years. Centers were stratified by hospital volume. The impact of LT programs was assessed after propensity score matching to achieve covariate balance. RESULTS: A total of 71,735 patients were identified, of which 7997 received LT (11.1%), 12,683 LR (17.7%), 15,675 RT (21.9%), and 35,380 CTx (49.3%). Among a total of 1267 distinct institutions, 94 (7.4%) were categorized as LT programs. Designation as an LT program was also associated with a high volume of LR and noncurative intent treatment (both P <0.001). After propensity score matching, LT programs were associated with better survival among LR and noncurative intent treatment patients. Although hospital volume was also associated with improved prognosis, LT programs were associated with additional survival benefits in noncurative intent treatment. On the other hand, no such benefit was noted in patients who underwent LR. CONCLUSIONS: The presence of an LT program was associated with a higher volume of LR and noncurative intent treatment. Furthermore, designation as an LT program had a "halo effect" on the prognosis of patients undergoing RT/CTx that went beyond the procedure-volume effect.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Humanos , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Hepatectomia
5.
Liver Transpl ; 29(4): 400-412, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36724877

RESUMO

Although both patients and physicians are key stakeholders in health care outcomes, patients and physicians often define success differently. The purpose of this study was to compare patient and physician perceptions of success 1 year after liver transplantation. This was a single-institution, qualitative study. We conducted in-person, semi-structured interviews with liver transplant recipients 1 year after transplantation and virtual interviews with transplant surgeons and hepatologists. Transcripts were coded and iteratively analyzed for themes using the principles of phenomenology. Twenty patients, 8 caregivers, 5 transplant surgeons, and 4 hepatologists were interviewed. Subject interviews averaged 57 (patient) and 27 (physician) minutes. Overall, patients and physicians had significant agreement in their definitions of success, which included avoidance of death, restoration of physical and mental function, return to society, acquisition of new health care knowledge, and open communication between the patient and the physician. Patients highlighted relief from worry about their future health status, and physicians highlighted decreased health care costs. Patients noted that a liver transplant did not have to be perfect, that is free from complications, to be successful. Physicians had a more stringent view and felt that any deviation from an ideal course reduced the relative success of a transplant. Detailed assessment of patient and physician responses reveals similar overall goals of regaining physical, mental, and emotional function. Complications are perceived differently by patients and physicians. Awareness of this discordance may serve to enhance relationships between transplant patients and their providers.


Assuntos
Gastroenterologistas , Transplante de Fígado , Médicos , Humanos , Transplante de Fígado/efeitos adversos , Médicos/psicologia , Comunicação , Pesquisa Qualitativa
6.
Br J Surg ; 110(11): 1527-1534, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37548041

RESUMO

BACKGROUND: Although liver resection is a viable option for patients with early-stage hepatocellular carcinoma (HCC), liver transplantation is the optimal treatment. The aim of this study was to identify characteristics of liver transplantation for elderly patients, and to assess the therapeutic benefit derived from liver transplantation over liver resection. METHODS: This was a population-based study of patients undergoing liver transplantation for HCC in the USA between 2004 and 2018. Data were retrieved from the National Cancer Database. Elderly patients were defined as individuals aged 70 years and over. Propensity score overlap weighting was used to control for heterogeneity between the liver resection and liver transplantation cohorts. RESULTS: Among 4909 liver transplant recipients, 215 patients (4.1 per cent) were classified as elderly. Among 5922 patients who underwent liver resection, 1907 (32.2 per cent) were elderly. Elderly patients who underwent liver transplantation did not have a higher hazard of dying during the first 5 years after transplantation than non-elderly recipients. After propensity score weighting, liver transplantation was associated with a lower risk of death than liver resection. Other factors associated with overall survival included diagnosis during 2016-2018, non-white/non-African American race, and α-fetoprotein level over 20 ng/dl. CONCLUSION: Elderly patients with HCC should not be excluded from liver transplantation based on age only. Transplantation leads to favourable survival compared with liver resection.

7.
Medicina (Kaunas) ; 59(7)2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37512101

RESUMO

Transplant oncology is a relatively new field in which transplantation is used to treat patients who would otherwise be unresectable. New anticancer treatment paradigms using tumor and transplant immunology and cancer immunogenomics are emerging. In turn, liver transplantation (LT) has become a potential therapy for certain patients with colorectal cancer (CRC) with liver metastasis, hepatocellular (HCC), cholangiocarcinoma (CCA), and metastatic neuroendocrine tumor (NET) of the liver. Although there are established criteria for LT in HCC, evidence regarding LT as a treatment modality for certain gastrointestinal malignancies is still debated. The aim of this review is to highlight updates in the role of LT for certain malignancies, including HCC, metastatic CRC, hilar CCA, and neuroendocrine tumor (NET), as well as contextualize LT use and discuss controversies in transplant oncology.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Neoplasias Gastrointestinais , Neoplasias Hepáticas , Transplante de Fígado , Tumores Neuroendócrinos , Humanos , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/patologia , Transplante de Fígado/efeitos adversos , Prova Pericial , Resultado do Tratamento , Neoplasias Gastrointestinais/cirurgia , Neoplasias Gastrointestinais/patologia , Ductos Biliares Intra-Hepáticos
8.
Am J Transplant ; 22(7): 1901-1908, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35182000

RESUMO

Liver allocation policy was changed to reduce variance in median MELD scores at transplant (MMaT) in February 2020. "Acuity circles" replaced local allocation. Understanding the impact of policy change on donor utilization is important. Ideal (I), standard (S), and non-ideal (NI) donors were defined. NI donors include older, higher BMI donors with elevated transaminases or bilirubin, history of hepatitis B or C, and all DCD donors. Utilization of I, S, and NI donors was established before and after allocation change and compared between low MELD (LM) centers (MMaT ≤ 28 before allocation change) and high MELD (HM) centers (MMaT > 28). Following reallocation, transplant volume increased nationally (67 transplants/center/year pre, 74 post, p .0006) and increased for both HM and LM centers. LM centers significantly increased use of NI donors and HM centers significantly increased use of I and S donors. Centers further stratify based on donor utilization phenotype. A subset of centers increased transplant volume despite rising MMaT by broadening organ acceptance criteria, increasing use of all donor types including DCD donors (98% increase), increasing living donation, and transplanting more frequently for alcohol associated liver disease. Variance in donor utilization can undermine intended effects of allocation policy change.


Assuntos
Doença Hepática Terminal , Transplante de Fígado , Obtenção de Tecidos e Órgãos , Doença Hepática Terminal/cirurgia , Humanos , Políticas , Doadores de Tecidos , Listas de Espera
9.
Ann Surg ; 276(5): 846-853, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35894433

RESUMO

OBJECTIVE: To define benchmark values for liver transplantation (LT) in patients with perihilar cholangiocarcinoma (PHC) enabling unbiased comparisons. BACKGROUND: Transplantation for PHC is used with reluctance in many centers and even contraindicated in several countries. Although benchmark values for LT are available, there is a lack of specific data on LT performed for PHC. METHODS: PHC patients considered for LT after Mayo-like protocol were analyzed in 17 reference centers in 2 continents over the recent 5-year period (2014-2018). The minimum follow-up was 1 year. Benchmark patients were defined as operated at high-volume centers (≥50 overall LT/year) after neoadjuvant chemoradiotherapy, with a tumor diameter <3 cm, negative lymph nodes, and with the absence of relevant comorbidities. Benchmark cutoff values were derived from the 75th to 25th percentiles of the median values of all benchmark centers. RESULTS: One hundred thirty-four consecutive patients underwent LT after completion of the neoadjuvant treatment. Of those, 89.6% qualified as benchmark cases. Benchmark cutoffs were 90-day mortality ≤5.2%; comprehensive complication index at 1 year of ≤33.7; grade ≥3 complication rates ≤66.7%. These values were better than benchmark values for other indications of LT. Five-year disease-free survival was largely superior compared with a matched group of nodal negative patients undergoing curative liver resection (n=106) (62% vs 32%, P <0.001). CONCLUSION: This multicenter benchmark study demonstrates that LT offers excellent outcomes with superior oncological results in early stage PHC patients, even in candidates for surgery. This provocative observation should lead to a change in available therapeutic algorithms for PHC.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Transplante de Fígado , Benchmarking , Colangiocarcinoma/cirurgia , Humanos , Tumor de Klatskin/patologia , Tumor de Klatskin/cirurgia , Padrão de Cuidado
10.
Am J Transplant ; 21(10): 3225-3238, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34212485

RESUMO

Although cellular transplantation remains a relatively small field compared to solid organ transplantation, the prospects for advancement in basic science and clinical care remain bountiful. In this review, notable historical events and the current landscape of the field of cellular transplantation are reviewed with an emphasis on islets (allo- and xeno-), hepatocytes (including bioartificial liver), adoptive regulatory immunotherapy, and stem cells (SCs, specifically endogenous organ-specific and mesenchymal). Also, the nascent but rapidly evolving field of three-dimensional bioprinting is highlighted, including its major processing steps and latest achievements. To reach its full potential where cellular transplants are a more viable alternative than solid organ transplants, fundamental change in how the field is regulated and advanced is needed. Greater public and private investment in the development of cellular transplantation is required. Furthermore, consistent with the call of multiple national transplant societies for allo-islet transplants, the oversight of cellular transplants should mirror that of solid organ transplants and not be classified under the unsustainable, outdated model that requires licensing as a drug with the Food and Drug Administration. Cellular transplantation has the potential to bring profound benefit through progress in bioengineering and regenerative medicine, limiting immunosuppression-related toxicity, and providing markedly reduced surgical morbidity.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Transplantes , Humanos , Tolerância Imunológica , Terapia de Imunossupressão , Células-Tronco
11.
Ann Hepatol ; 24: 100318, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33515801

RESUMO

INTRODUCTION AND OBJECTIVES: The success of direct-acting antivirals (DAA) has transformed the management of hepatitis C virus (HCV) infection and has led to the expansion of the deceased donor organ pool for liver transplantation. MATERIAL AND METHODS: We present a single center retrospective review of liver transplantations performed on HCV-seronegative recipients from HCV-seropositive organs from 11/2017 to 05/2020. HCV nucleic acid testing (NAT) was performed on HCV-seropositive donors to assess active HCV infection. RESULTS: 42 HCV-seronegative recipients underwent a liver transplant from a HCV-seropositive donor, including 21 NAT negative (20 liver, 1 simultaneous liver kidney transplant) and 21 NAT positive liver transplants. Two (9.5%) HCV antibody positive/NAT negative recipients developed HCV viremia and achieved sustained virologic response with DAA therapy. The remaining patients with available data (19 patients) remained polymerase chain reaction (PCR) negative at 6 months. 20 (95%) of HCV antibody positive/NAT positive recipients had a confirmed HCV viremia. 100% of patients with available data (15 patients) achieved SVR. Observed events include 1 mortality and graft loss and equivalent rates of post-transplant complications between NAT positive and NAT negative recipients. CONCLUSIONS: HCV-seropositive organs can be safely transplanted into HCV-seronegative patients with minimal complications post-transplant.


Assuntos
Seleção do Doador , Hepacivirus/isolamento & purificação , Hepatite C/diagnóstico , Hepatopatias/cirurgia , Hepatopatias/virologia , Transplante de Fígado , Adulto , Idoso , Antivirais/uso terapêutico , Feminino , Hepatite C/epidemiologia , Hepatite C/terapia , Humanos , Hepatopatias/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resposta Viral Sustentada , Resultado do Tratamento
12.
Clin Transplant ; 34(12): e14115, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33048383

RESUMO

The use of diabetic kidneys is increasing worldwide with better outcome than being on waitlist and possible reversal of diabetic changes in transplanted kidneys. But particular caution is warranted in diabetic donor-recipient combination. Total 1223 deceased donor kidney transplants were performed at our center between 2008 and 2018. 689 from non-diabetic donor (NDD) to non-diabetic recipient, 400 from non-diabetic donor to diabetic recipient, 97 from diabetic to non-diabetic recipient, and 32 from diabetic donor (DD) to diabetic recipient. The DD was older than NDDs (median age 48 vs 39 years, P < 0.0001). DD had higher BMI (35.6 vs 26.9, P < 0.0001), higher KDPI (74% vs 37%, P < 0.0001), and higher terminal creatinine (1.10 mg/dl vs 0.95 mg/dl, p 0.0046) than the NDD. Diabetes recipients were comparatively older (57 vs 54, P < 0.001). DD recipients had higher serum creatinine at 6 months (1.70 vs 1.50 mg/dl, p 0.00304) and 2 years post-transplant (1.70 vs 1.50 mg/dl P < 0.0002). DD recipients had more favorable end CPRA than NDD recipients (77.5% at 0% vs 67.4% at 0, P = 0.0074). Ten-year patient and graft survival was best in NDD-recipient pair and worse in DD-recipient pair. Diabetic donor kidneys to diabetic recipients have lower 1-, 3-, and 5-year graft survival.


Assuntos
Diabetes Mellitus , Transplante de Rim , Sobrevivência de Enxerto , Humanos , Rim , Pessoa de Meia-Idade , Doadores de Tecidos
13.
Proc Natl Acad Sci U S A ; 112(21): 6682-7, 2015 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-25964334

RESUMO

V-domain immunoglobulin suppressor of T-cell activation (VISTA) is a negative immune-checkpoint protein that suppresses T-cell responses. To determine whether VISTA synergizes with another immune-checkpoint, programmed death 1 (PD-1), this study characterizes the immune responses in VISTA-deficient, PD-1-deficient (KO) mice and VISTA/PD-1 double KO mice. Chronic inflammation and spontaneous activation of T cells were observed in both single KO mice, demonstrating their nonredundancy. However, the VISTA/PD-1 double KO mice exhibited significantly higher levels of these phenotypes than the single KO mice. When bred onto the 2D2 T-cell receptor transgenic mice, which are predisposed to development of inflammatory autoimmune disease in the CNS, the level of disease penetrance was significantly enhanced in the double KO mice compared with in the single KO mice. Consistently, the magnitude of T-cell response toward foreign antigens was synergistically higher in the VISTA/PD-1 double KO mice. A combinatorial blockade using monoclonal antibodies specific for VISTA and PD-L1 achieved optimal tumor-clearing therapeutic efficacy. In conclusion, our study demonstrates the nonredundant role of VISTA that is distinct from the PD-1/PD-L1 pathway in controlling T-cell activation. These findings provide the rationale to concurrently target VISTA and PD-1 pathways for treating T-cell-regulated diseases such as cancer.


Assuntos
Proteínas de Membrana/imunologia , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T/imunologia , Animais , Anticorpos Monoclonais/administração & dosagem , Antígenos/administração & dosagem , Antígeno B7-H1/deficiência , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Feminino , Tolerância Imunológica , Ligantes , Ativação Linfocitária , Masculino , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Neoplasias Experimentais/imunologia , Receptor de Morte Celular Programada 1/deficiência , Receptor de Morte Celular Programada 1/genética
14.
Proc Natl Acad Sci U S A ; 111(41): 14846-51, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25267631

RESUMO

V domain-containing Ig suppressor of T-cell activation (VISTA) is a negative checkpoint regulator that suppresses T cell-mediated immune responses. Previous studies using a VISTA-neutralizing monoclonal antibody show that VISTA blockade enhances T-cell activation. The current study describes a comprehensive characterization of mice in which the gene for VISTA has been deleted. Despite the apparent normal hematopoietic development in young mice, VISTA genetic deficiency leads to a gradual accumulation of spontaneously activated T cells, accompanied by the production of a spectrum of inflammatory cytokines and chemokines. Enhanced T-cell responsiveness was also observed upon immunization with neoantigen. Despite the presence of multiorgan chronic inflammation, aged VISTA-deficient mice did not develop systemic or organ-specific autoimmune disease. Interbreeding of the VISTA-deficient mice with 2D2 T-cell receptor transgenic mice, which are predisposed to the development of experimental autoimmune encephalomyelitis, drastically enhanced disease incidence and intensity. Disease development is correlated with the increase in the activation of encephalitogenic T cells in the periphery and enhanced infiltration into the CNS. Taken together, our data suggest that VISTA is a negative checkpoint regulator whose loss of function lowers the threshold for T-cell activation, allowing for an enhanced proinflammatory phenotype and an increase in the frequency and intensity of autoimmunity under susceptible conditions.


Assuntos
Autoimunidade/genética , Autoimunidade/imunologia , Antígenos B7/genética , Predisposição Genética para Doença , Inflamação/patologia , Envelhecimento/patologia , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Antígenos B7/deficiência , Antígenos B7/metabolismo , Quimiocinas/metabolismo , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Hematopoese , Ativação Linfocitária/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Células Th1/imunologia , Células Th17/imunologia
15.
J Immunol ; 193(7): 3816-24, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25172484

RESUMO

Recipient CD4 T regulatory cells inhibit the acute T cell-mediated rejection of renal allografts in wild-type mice. The survival of single class II MHC-disparate H-2(bm12) renal allografts was tested in B6.CCR5(-/-) recipients, which have defects in T regulatory cell activities that constrain alloimmune responses. In contrast to wild-type C57BL/6 recipients, B6.CCR5(-/-) recipients rejected the bm12 renal allografts. However, donor-reactive CD8 T cells rather than CD4 T cells were the primary effector T cells mediating rejection. The CD8 T cells induced to bm12 allografts in CCR5-deficient recipients were reactive to peptides spanning the 3 aa difference in the I-A(bm12) versus I-A(b) ß-chains presented by K(b) and D(b) class I MHC molecules. Allograft-primed CD8 T cells from CCR5-deficient allograft recipients were activated during culture either with proinflammatory cytokine-stimulated wild-type endothelial cells pulsed with the I-A(bm12) peptides or with proinflammatory cytokine-simulated bm12 endothelial cells, indicating their presentation of the I-A(bm12) ß-chain peptide/class I MHC complexes. In addition to induction by bm12 renal allografts, the I-A(bm12) ß-chain-reactive CD8 T cells were induced in CCR5-deficient, but not wild-type C57BL/6, mice by immunization with the peptides. These results reveal novel alloreactive CD8 T cell specificities in CCR5-deficient recipients of single class II MHC renal allografts that mediate rejection of the allografts.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Transplante de Rim , Receptores CCR5/imunologia , Aloenxertos , Animais , Linfócitos T CD8-Positivos/patologia , Citocinas/genética , Citocinas/imunologia , Rejeição de Enxerto/genética , Rejeição de Enxerto/patologia , Antígenos H-2/genética , Antígenos H-2/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Camundongos , Camundongos Knockout , Receptores CCR5/genética
17.
Transplant Proc ; 56(2): 267-277, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38341297

RESUMO

PURPOSE: Clinical judgment in renal donor organ and recipient selection is gained through fellowship and mentorship in early career. We aim to understand the past and current state of organ acceptance education. METHODS: We developed and distributed an anonymous, national survey to American Society of Transplant Surgeons faculty members and transplant surgery fellows in 2022. Survey questions explored in detail the evaluation of organ offers, the extent of formal education in organ evaluation, and attitudes regarding training adequacy. FINDINGS: Ninety-eight attending surgeons (65 men, 25 women, and 3 nonbinary) and 38 fellows (25 men, 6 women, and 2 nonbinary) responded. Seventy-eight percent of attending surgeons and 6% of fellows take primary organ offers. Forty-four percent of fellows report no didactic education in donor evaluation and recipient selection. Fellows report that discussion with attending surgeons (37.2%) and independent study of the literature (35.4%) are their primary modes of learning. Fellows call for additional clinical decision-making experience (47.3%), further didactic sessions (44.7%), and additional discussions with faculty (44.7%). Sixty-four percent of fellows and 55% of attendings felt their training provided adequate education about donor selection. CONCLUSION: Our responses suggest gaps in education regarding donor and recipient selection. Increased clinical experience and standardized education at the national level represent opportunities for improvement.


Assuntos
Currículo , Educação de Pós-Graduação em Medicina , Masculino , Humanos , Feminino , Estados Unidos , Inquéritos e Questionários , Escolaridade , Atitude do Pessoal de Saúde
18.
JAMA Surg ; 159(2): 211-218, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38055245

RESUMO

Importance: Liver malignancies are an increasing global health concern with a high mortality. We review outcomes following liver transplant for primary and secondary hepatic malignancies. Observations: Transplant may be a suitable treatment option for primary and secondary hepatic malignancies in well-selected patient populations. Conclusions and Relevance: Many patients with primary or secondary liver tumors are not eligible for liver resection because of advanced underlying liver disease or high tumor burden, precluding complete tumor clearance. Although liver transplant has been a long-standing treatment modality for patients with hepatocellular carcinoma, recently transplant has been considered for patients with other malignant diagnoses. In particular, while well-established for hepatocellular carcinoma and select patients with perihilar cholangiocarcinoma, transplant has been increasingly used to treat patients with intrahepatic cholangiocarcinoma, as well as metastatic disease from colorectal liver and neuroendocrine primary tumors. Because of the limited availability of grafts and the number of patients on the waiting list, optimal selection criteria must be further defined. The ethics of organ allocation to individuals who may benefit from prolonged survival after transplant yet have a high incidence of recurrence, as well as the role of living donation, need to be further discerned in the setting of transplant oncology.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Transplante de Fígado , Tumores Neuroendócrinos , Humanos , Carcinoma Hepatocelular/cirurgia , Transplante de Fígado/efeitos adversos , Neoplasias Hepáticas/secundário , Colangiocarcinoma/cirurgia , Tumores Neuroendócrinos/secundário , Ductos Biliares Intra-Hepáticos
19.
J Am Coll Surg ; 238(3): 291-302, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38050968

RESUMO

BACKGROUND: Social determinants of health can impact the quality of liver transplantation (LT) care. We sought to assess whether the association between neighborhood deprivation and transplant outcomes can be mitigated by receiving care at high-quality transplant centers. STUDY DESIGN: In this population-based cohort study, patients who underwent LT between 2004 and 2019 were identified in the Scientific Registry of Transplant Recipients. LT-recipient neighborhoods were identified at the county level and stratified into quintiles relative to Area Deprivation Index (ADI). Transplant center quality was based on the Scientific Registry of Transplant Recipients 5-tier ranking using standardized transplant rate ratios. Multivariable Cox regression was used to assess the relationship between ADI, hospital quality, and posttransplant survival. RESULTS: A total of 41,333 recipients (median age, 57.0 [50.0 to 63.0] years; 27,112 [65.4%] male) met inclusion criteria. Patients residing in the most deprived areas were more likely to have nonalcoholic steatohepatitis, be Black, and travel further distances to reach a transplant center. On multivariable analysis, post-LT long-term mortality was associated with low- vs high-quality transplant centers (hazard ratio [HR] 1.19, 95% CI 1.07 to 1.32), as well as among patients residing in high- vs low-ADI neighborhoods (HR 1.25, 95% CI 1.16 to 1.34; both p ≤ 0.001). Of note, individuals residing in high- vs low-ADI neighborhoods had a higher risk of long-term mortality after treatment at a low-quality (HR 1.31, 95% CI 1.06 to 1.62, p = 0.011) vs high-quality (HR 1.12, 95% CI 0.83 to 1.52, p = 0.471) LT center. CONCLUSIONS: LT at high-quality centers may be able to mitigate the association between posttransplant survival and neighborhood deprivation. Investments and initiatives that increase access to referrals to high-quality centers for patients residing in higher deprivation may lead to better outcomes and help mitigate disparities in LT.


Assuntos
Transplante de Fígado , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos de Coortes , Sistema de Registros , Transplantados , Estudos Retrospectivos
20.
Transplantation ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995240

RESUMO

BACKGROUND: We sought to define the survival benefit of kidney transplantation versus long-term dialysis relative to waitlist time on dialysis, social vulnerability, and age among end-stage renal transplant candidates. METHODS: End-stage renal disease patients who were candidates for their first deceased donor kidney transplantation between 2008 and 2020 were identified using the US Renal Data System. Survival probabilities for patient survival were compared using the restricted mean survival times (RMSTs) across different age and social vulnerability index (SVI) ranges. RESULTS: Among 149 923 patients, 68 795 (45.9%) patients underwent a kidney transplant and 81 128 (54.1%) remained on dialysis. After propensity-score matching (n = 58 035 in each cohort), the 5-y RMST difference between kidney transplant and dialysis demonstrated an increasing trend in mean life-years gained within 5 y of follow-up relative to advancing age (<30 y: 0.40 y, 95% confidence interval, 0.36-0.44 y versus >70 y: 0.75 y, 95% confidence interval, 0.70-0.80 y). Conversely, disparities in 5-y RMSTs remained consistent relative to social vulnerability (median 5-y RMST difference: 0.62 y comparing low versus high SVI). When considering waitlist duration, stratified analyses demonstrated increasing trends across different age groups with the largest RMST differences observed among older patients aged ≥70 y. Notably, longer waitlist durations (>3 y) yielded more pronounced RMST differences compared with shorter durations (<1 y). CONCLUSIONS: These data underscore the survival benefit associated with kidney transplantation over long-term dialysis across various age and SVI ranges. Transplantation demonstrated a greater advantage among older patients who had a longer waitlist duration.

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