Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 84
Filtrar
1.
Am J Transplant ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39278626

RESUMO

Immunotherapy can significantly improve efficacy of cancer treatments. For locally advanced stage III lung cancers, chemoimmunotherapy in the neoadjuvant setting can achieve complete pathological response in about 40% of cases. However, optimal cancer response in patients receiving immunotherapy is sometimes associated with potentially fatal bystander injury to lung and liver. We report a successful combined double lung and liver transplantation for immunotherapy-associated respiratory failure and cirrhosis in a patient with advanced lung cancer. A 68-year-old man with stage IIIA squamous cell lung cancer encountered severe interstitial pneumonitis and nodular regenerative hyperplasia of the liver following systemic anticancer therapy that included immunotherapy and platinum-based chemotherapy. These adverse events culminated into fulminant end-stage pulmonary fibrosis and cirrhosis, which were treated with simultaneous lung and liver transplantation, complete resection of lung cancer, and mediastinal lymphadenectomy. The patient demonstrated promising early outcomes without recurrence of cancer at 12 months. Given that oncologic treatments can induce irreversible solid organ failure despite cancer control, our report suggests that in carefully selected patients without systemic metastasis and in whom complete resection of residual cancer can be performed, organ transplantation can be life-saving.

2.
Am J Transplant ; 24(8): 1362-1368, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38219866

RESUMO

Mouse models have been instrumental in understanding mechanisms of transplant rejection and tolerance, but cross-study reproducibility and translation of experimental findings into effective clinical therapies are issues of concern. The Mouse Models in Transplantation symposium gathered scientists and physician-scientists involved in basic and clinical research in transplantation to discuss the strengths and limitations of mouse transplant models and strategies to enhance their utility. Participants recognized that increased procedure standardization, including the use of prespecified, defined endpoints, and statistical power analyses, would benefit the field. They also discussed the generation of new models that incorporate environmental and genetic variables affecting clinical outcomes as potentially important. If implemented, these strategies are expected to improve the reproducibility of mouse studies and increase their translation to clinical trials and, ideally, new Food and Drug Administration-approved drugs.


Assuntos
Modelos Animais de Doenças , Animais , Camundongos , Humanos , Rejeição de Enxerto/prevenção & controle , Rejeição de Enxerto/etiologia , Transplante de Órgãos , Modelos Animais , Reprodutibilidade dos Testes , Transplante/métodos
3.
Kidney Int ; 104(3): 463-469, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37391039

RESUMO

Kidney damage due to ischemia or rejection results in the accumulation of unfolded and misfolded proteins in the endoplasmic reticulum (ER) lumen, a condition known as "ER stress." Inositol-requiring enzyme 1α (IRE1α), the first ER stress sensor found, is a type I transmembrane protein with kinase and endoribonuclease activity. On activation, IRE1α nonconventionally splices an intron from unspliced X-box-binding protein 1 (XBP1) mRNA to produce XBP1s mRNA that encodes the transcription factor, XBP1s, for the expression of genes encoding proteins that mediate the unfolded protein response. The unfolded protein response promotes the functional fidelity of ER and is required for secretory cells to sustain protein folding and secretory capability. Prolonged ER stress can lead to apoptosis, which may result in detrimental repercussions to organ health and has been implicated in the pathogenesis and progression of kidney diseases. The IRE1α-XBP1 signaling acts as a major arm of unfolded protein response and is involved in regulating autophagy, cell differentiation, and cell death. IRE1α also interacts with activator protein-1 and nuclear factor-κB pathways to regulate inflammatory responses. Studies using transgenic mouse models highlight that the roles of IRE1α differ depending on cell type and disease setting. This review covers these cell-specific roles of IRE1α signaling and the potential for therapeutic targeting of this pathway in the context of ischemia and rejection affecting the kidneys.


Assuntos
Endorribonucleases , Proteínas Serina-Treonina Quinases , Animais , Estresse do Retículo Endoplasmático/genética , Endorribonucleases/genética , Endorribonucleases/metabolismo , Rejeição de Enxerto , Inositol/metabolismo , Rim/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/metabolismo , Resposta a Proteínas não Dobradas , Humanos
4.
Am J Transplant ; 23(3): 437-439, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36695683

RESUMO

A 62-year-old received orthotopic liver transplantation. Three weeks later, thrombotic microangiopathy developed. Testing revealed thrombotic thrombocytopenic purpura (TTP) characterized by low ADAMTS13 (A Disintegrin-like Metallopeptidase with ThromboSpondin type 1 motif 13) activity and no inhibitor of ADAMTS13 protein. Retrospective attainment of donor records revealed a TTP diagnosis, presumably hereditary TTP (hTTP), as an ADAMTS13 protein inhibitor was not mentioned. As the grafted liver does not produce ADAMTS13 protein, the recipient now functionally has hTTP and will likely need plasma transfusions indefinitely. While hTTP is extremely rare, it should be considered a contraindication to liver donation outside of exceptional circumstances. If a potential liver donor has TTP listed on medical history, attempts should be made to determine whether it is autoimmune or hereditary. An accurate medical history is critical as it is the only reliable way to identify hTTP, as outside of acute exacerbations of TTP, donors with hTTP can have normal laboratory values, including normal hemoglobin, platelets, and renal function.


Assuntos
Transplante de Fígado , Púrpura Trombocitopênica Trombótica , Microangiopatias Trombóticas , Humanos , Pessoa de Meia-Idade , Púrpura Trombocitopênica Trombótica/diagnóstico , Proteína ADAMTS13 , Estudos Retrospectivos
5.
Rheumatology (Oxford) ; 62(3): 1306-1316, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35900152

RESUMO

OBJECTIVES: Lung fibrosis is the leading cause of death in SSc, with no cure currently available. Antifibrotic Endostatin (ES) production does not reach therapeutic levels in SSc patients, suggesting a deficit in its release from Collagen XVIII by the main cleavage enzyme, Cathepsin L (CTSL). Thus, elucidating a potential deficit in CTSL expression and activity unravels an underlying molecular cause for SSc-driven lung fibrosis. METHODS: Fibrosis was induced experimentally using TGF-ß in vitro, in primary human lung fibroblasts (pLFs), and ex vivo, in human lung tissues. ES and CTSL expression was quantified using ELISA, RT-qPCR, immunoblotting or immunofluorescence. Recombinant NC1-FLAG peptide was used to assess CTSL cleavage activity. CTSL expression was also compared between SSc vs normal (NL)-derived pLFs and lung tissues. RESULTS: ES levels were significantly reduced in media conditioned by TGF-ß-induced pLFs. TGF-ß-stimulated pLFs significantly reduced expression and secretion of CTSL into the extracellular matrix (ECM). CTSL was also sequestered in its inactive form into extracellular vesicles, further reducing its availability in the ECM. Media conditioned by TGF-ß-induced pLFs showed reduced cleavage of NC1-Flag and reduced release of the antifibrotic ES fragment. SSc-derived pLFs and lung tissues expressed significantly lower levels of CTSL compared with NL. CONCLUSIONS: Our findings identify CTSL as a protein protective against lung fibrosis via its activation of antifibrotic ES, and whose expression in SSc pLFs and lung tissues is suppressed. Identifying strategies to boost CTSL endogenous levels in SSc patients could serve as a viable therapeutic strategy.


Assuntos
Fibrose Pulmonar , Escleroderma Sistêmico , Humanos , Catepsina L/metabolismo , Células Cultivadas , Fibroblastos/metabolismo , Fibrose , Fibrose Pulmonar/patologia , Escleroderma Sistêmico/patologia , Pele/patologia , Fator de Crescimento Transformador beta/metabolismo
6.
Am J Transplant ; 22(11): 2502-2508, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35612993

RESUMO

Connexins are a class of membrane proteins widely distributed throughout the body and have various functions based on their location and levels of expression. More specifically, connexin proteins expressed in endothelial cells (ECs) have unique roles in maintaining EC barrier integrity and function-a highly regulated process that is critical for pro-inflammatory and pro-coagulant reactions. In this minireview, we discuss the regulatory influence connexin proteins have in maintaining EC barrier integrity and their role in ischemia-reperfusion injury as it relates to organ transplantation. It is evident that certain isoforms of the connexin protein family are uniquely positioned to have far-reaching effects on preserving organ function; however, there is still much to be learned of their roles in transplant immunology and the application of this knowledge to the development of targeted therapeutics.


Assuntos
Transplante de Órgãos , Traumatismo por Reperfusão , Humanos , Células Endoteliais/metabolismo , Conexinas/uso terapêutico , Traumatismo por Reperfusão/metabolismo , Preservação de Órgãos
7.
Am J Transplant ; 22(5): 1293-1298, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35224837

RESUMO

Patients undergoing organ transplantation transition from one life-altering issue (organ dysfunction) to a lifelong commitment-immunosuppression. Regimens of immunosuppressive agents (ISAs) come with significant side effects and comorbidities. Recently, the use of nanoparticles (NPs) as a solution to the problems associated with the long-term and systemic use of ISAs in transplantation has emerged. This minireview describes the role of NPs in organ transplantation and discusses obstacles to clinical implementation and pathways to clinical translation.


Assuntos
Imunossupressores , Transplante de Órgãos , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/prevenção & controle , Humanos , Tolerância Imunológica , Terapia de Imunossupressão , Imunossupressores/uso terapêutico
8.
Am J Transplant ; 22(2): 386-401, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34714588

RESUMO

Early insults associated with cardiac transplantation increase the immunogenicity of donor microvascular endothelial cells (ECs), which interact with recipient alloreactive memory T cells and promote responses leading to allograft rejection. Thus, modulating EC immunogenicity could potentially alter T cell responses. Recent studies have shown modulating mitochondrial fusion/fission alters immune cell phenotype. Here, we assess whether modulating mitochondrial fusion/fission reduces EC immunogenicity and alters EC-T cell interactions. By knocking down DRP1, a mitochondrial fission protein, or by using the small molecules M1, a fusion promoter, and Mdivi1, a fission inhibitor, we demonstrate that promoting mitochondrial fusion reduced EC immunogenicity to allogeneic CD8+ T cells, shown by decreased T cell cytotoxic proteins, decreased EC VCAM-1, MHC-I expression, and increased PD-L1 expression. Co-cultured T cells also displayed decreased memory frequencies and Ki-67 proliferative index. For in vivo significance, we used a novel murine brain-dead donor transplant model. Balb/c hearts pretreated with M1/Mdivi1 after brain-death induction were heterotopically transplanted into C57BL/6 recipients. We demonstrate that, in line with our in vitro studies, M1/Mdivi1 pretreatment protected cardiac allografts from injury, decreased infiltrating T cell production of cytotoxic proteins, and prolonged allograft survival. Collectively, our data show promoting mitochondrial fusion in donor ECs mitigates recipient T cell responses and leads to significantly improved cardiac transplant survival.


Assuntos
Transplante de Coração , Dinâmica Mitocondrial , Animais , Linfócitos T CD8-Positivos , Células Endoteliais , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
9.
J Clin Apher ; 37(4): 411-414, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35238425

RESUMO

Low-density lipoprotein (LDL) apheresis has been shown to improve remission in patients with steroid-resistant nephrotic syndrome (SRNS). Here, we report a case study of two patients who failed apheresis treatment for SRNS and required transplant with subsequent recurrence of nephrotic syndrome and response to apheresis treatment. Two patients were treated with 12 sessions of LDL apheresis for SRNS without improvement and subsequently required renal transplantation. The first patient received an ABO-incompatible kidney transplant requiring plasma exchange (PE) with subsequent recurrence of focal segmental glomerulosclerosis. The second patient also received a renal transplant after treatment failure and subsequently developed recurrence of nephrotic syndrome in the transplanted kidney. Both patients underwent repeat therapy with lipoprotein apheresis. The first patient underwent lipoprotein apheresis after completing PE with significant improvement in serum creatinine and urine protein creatinine ratio. Three years later, he continued to do well and remains in remission. The second patient also responded well to repeat therapy with lipoprotein apheresis and had significant improvement with a urine protein creatinine ratio of 0.8 and a serum creatinine of 0.9 mg/dL 6 months after transplant. Lipoprotein apheresis was able to result in remission of nephrotic syndrome in these patients with posttransplant recurrence of disease. This is the first report of patients not responding to treatment pretransplant but responding posttransplant. Lipoprotein apheresis should be considered in patients with recurrence of nephrotic syndrome after renal transplantation even with a history of treatment failure prior to transplantation.


Assuntos
Remoção de Componentes Sanguíneos , Glomerulosclerose Segmentar e Focal , Transplante de Rim , Síndrome Nefrótica , Criança , Creatinina , Glomerulosclerose Segmentar e Focal/terapia , Humanos , Lipoproteínas LDL , Masculino , Síndrome Nefrótica/etiologia , Síndrome Nefrótica/terapia , Recidiva
10.
Am J Transplant ; 21(6): 2067-2078, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33210808

RESUMO

Complement is known to play a role in ischemia and reperfusion injury (IRI). A general paradigm is that complement is activated by self-reactive natural IgM antibodies (nAbs), after they engage postischemic neoepitopes. However, a role for nAbs in lung transplantation (LTx) has not been explored. Using mouse models of LTx, we investigated the role of two postischemic neoepitopes, modified annexin IV (B4) and a subset of phospholipids (C2), in LTx. Antibody deficient Rag1-/- recipient mice were protected from LTx IRI. Reconstitution with either B4 or C2nAb restored IRI, with C2 significantly more effective than B4 nAb. Based on these information, we developed/characterized a novel complement inhibitor composed of single-chain antibody (scFv) derived from the C2 nAb linked to Crry (C2scFv-Crry), a murine inhibitor of C3 activation. Using an allogeneic LTx, in which recipients contain a full nAb repertoire, C2scFv-Crry targeted to the LTx, inhibited IRI, and delayed acute rejection. Finally, we demonstrate the expression of the C2 neoepitope in human donor lungs, highlighting the translational potential of this approach.


Assuntos
Lesão Pulmonar , Transplante de Pulmão , Traumatismo por Reperfusão , Transplantes , Animais , Inativadores do Complemento , Humanos , Imunoglobulina M , Transplante de Pulmão/efeitos adversos , Camundongos , Traumatismo por Reperfusão/prevenção & controle
11.
Am J Transplant ; 20(8): 1969-1983, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32406604

RESUMO

Tacrolimus (Tac) is widely used to prevent rejection and graft loss in solid organ transplantation. A limiting characteristic of Tac is the high intra and interpatient variability associated with its use. Routine therapeutic drug monitoring (TDM) is necessary to facilitate Tac management and to avoid undesirable clinical outcomes. However, whole blood trough concentrations commonly utilized in TDM are not strong predictors of the detrimental clinical outcomes of interest. Recently, researchers have focused on Tac intrapatient variability (Tac IPV) as a novel marker to better assess patient risk. Higher Tac IPV has been associated with a number of mechanisms leading to shortened graft survival. Medication nonadherence (MNA) is considered to be the primary determinant of high Tac IPV and perhaps the most modifiable risk factor. An understanding of the methodology behind Tac IPV is imperative to its recognition as an important prognostic measure and integration into clinical practice. Therapeutic interventions targeting MNA and reducing Tac IPV are crucial to improving long-term graft survival.


Assuntos
Transplante de Rim , Tacrolimo , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico
12.
Clin Chem ; 66(12): 1531-1537, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32894753

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody testing is an important tool in assessment of pandemic progress, contact tracing, and identification of recovered coronavirus disease 2019 (COVID-19) patients. We evaluated an orthogonal testing algorithm (OTA) to improve test specificity in these use cases. METHODS: A two-step OTA was applied where individuals who initially tested positive were tested with a second test. The first-line test, detecting IgG antibodies to the viral nucleocapsid protein, was validated in 130 samples and the second-line test, detecting IgG antibodies to the viral spike protein in 148 samples. The OTA was evaluated in 4333 clinical patient specimens. The seropositivity rates relative to the SARS-CoV-2 PCR positivity rates were evaluated from our entire patient population data (n = 5102). RESULTS: The first-line test resulted in a clinical sensitivity of 96.4% (95% CI; 82.3% to 99.4%), and specificity of 99.0% (95% CI; 94.7% to 99.8%), whereas the second-line test had a sensitivity of 100% (95% CI; 87.1% to 100%) and specificity of 98.4% (95% CI; 94.2% to 99.5%). Using the OTA, 78/98 (80%) of initially positive SARS-CoV-2 IgG results were confirmed with a second-line test, while 11/42 (26%) of previously diagnosed COVID-19 patients had no detectable antibodies as long as 94 days post PCR diagnosis. CONCLUSION: Our results show that an OTA can be used to identify patients who require further follow-up due to potential SARS CoV-2 IgG false positive results. In addition, serological testing may not be sufficiently sensitive to reliably detect prior COVID-19 infection.


Assuntos
Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Imunoglobulina G/sangue , SARS-CoV-2/química , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Anticorpos Antivirais/imunologia , COVID-19/sangue , Estudos de Coortes , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/imunologia , Pessoa de Meia-Idade , Fosfoproteínas/imunologia , Sensibilidade e Especificidade , South Carolina , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto Jovem
13.
Clin Transplant ; 34(4): e13844, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32092187

RESUMO

Medication non-adherence is common after transplant and a major contributor to graft loss. The objective of this pilot study was to obtain preliminary safety and adherence data of a complete once-daily immunosuppression regimen of Extended-release-tacrolimus (LCP-tac), everolimus, and prednisone vs LCP-tac, mycophenolate Twice daily (BID), and prednisone through a randomized controlled pilot study of 40 patients (20 in each arm). At 3 ± 2 months post-transplant, patients were randomized to receive LCP-tac and everolimus once daily or LCP-tac and mycophenolate BID (control arm) for 6 months; 80 met eligibility, and 40 were randomized. Mean age was 51 ± 14 years, 33% were female, 45% African American, and 55% had a Calculated panel reactive antibody (cPRA) >20%. Both regimens were well-tolerated, and medication side effect burden tended to be less severe in the intervention group. Self-reported high medication adherence decreased in the control arm from baseline to 6 months (80%-59%), while remaining the same in the intervention arm throughout the study (45%-47%). For safety assessment, there was no rejection, graft loss, or death in either arm. These results provide preliminary evidence of the safety of a novel once-daily immunosuppression regimen. The impact of this once-daily regimen on medication adherence requires a larger long-term study.


Assuntos
Transplante de Rim , Adulto , Idoso , Esquema de Medicação , Feminino , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Humanos , Terapia de Imunossupressão , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Tacrolimo
14.
Clin Transplant ; 34(10): e14006, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32524643

RESUMO

Opioid use after kidney transplant has been shown to be a risk factor for chronic opioid use, which leads to an increased risk of mortality. The purpose of this study was to evaluate the early impact of a multimodal pain regimen and education quality improvement program on opioid use after kidney transplant 2 months after implementation. This was a retrospective, single-center analysis of post-operative opioid use, comparing the average daily Morphine milligram equivalents (MME) of the patients who received education on opioids and a multimodal pain regimen (preoperative TAP/QL block, scheduled APAP and gabapentin) compared to a historical control group. Despite having no differences in pre-transplant opioid exposure, daily and overall inpatient opioid utilization was significantly reduced in the multimodal pain protocol cohort (38.6 vs 8.0 MME/day; P < .001); 5% of patients in the multimodal pain protocol cohort were discharged with an opioid prescription, compared to 96% of controls (P < .001). Our early results demonstrate that a multimodal pain protocol can effectively and dramatically reduce short-term opioid utilization in kidney transplant recipients.


Assuntos
Transplante de Rim , Transtornos Relacionados ao Uso de Opioides , Analgésicos Opioides/uso terapêutico , Humanos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Estudos Retrospectivos
15.
Ren Fail ; 42(1): 1152-1156, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33203287

RESUMO

BACKGROUND: Allo-antigen-specific T-cytotoxic memory cells (TcM) which express CD40 ligand (CD154) in overnight lymphocyte co-culture are strongly associated with acute cellular rejection (ACR) seen in "for cause" biopsies for renal allograft dysfunction. Specifically, when the likelihood of rejection is increased, donor-specific allospecific TcM exceed those induced by HLA-non-identical third-party cell by 1.15-fold or greater. METHODS: The performance of allospecific TcM was evaluated retrospectively in primary renal transplant recipients (RTR) at routine clinical visits, cross-sectionally at presentation for biopsies, and serially. Performance metrics were sensitivity, specificity, positive and negative predictive values (PPV and NPV). RESULTS: Twenty-two primary RTR, median age 45 years (range 19-72) were tested with allospecific CD154 + TcM. Samples were obtained at the mean ± SD time interval of 806 ± 239 days after kidney transplantation. Six of 22 patients experienced biopsy proven T- Cell Mediated Rejection (TCMR). A seventh showed antibody mediated rejection (ABMR). Of these seven patients six demonstrated increased likelihood of rejection with allospecific TcM (sensitivity 83%). Ten of these 15 patients with no rejection had a negative test (specificity 67%). False positive tests were seen in five patients. Six out of 11 patients with positive tests had ACR/ABMR with a PPV of 54%, while 10 out of 11 patients with negative tests were non-rejecters with a NPV of 91%. CONCLUSION: Allospecific T-cytotoxic memory cells distinguished primary RTR with quiescent allografts from those with dysfunction. With serial surveillance measures, this test system may facilitate decisions to manage immunosuppression in RTR.


Assuntos
Ligante de CD40/metabolismo , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/imunologia , Transplante de Rim/efeitos adversos , Linfócitos T Citotóxicos/imunologia , Adulto , Idoso , Aloenxertos , Feminino , Rejeição de Enxerto/patologia , Humanos , Memória Imunológica , Terapia de Imunossupressão , Rim/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
16.
Am J Respir Cell Mol Biol ; 60(6): 678-686, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30571141

RESUMO

Chronic obstructive pulmonary disease-associated chronic inflammation has been shown to lead to an autoimmune phenotype characterized in part by the presence of lung autoreactive antibodies. We hypothesized that ischemia-reperfusion injury (IRI) liberates epitopes that would facilitate preexisting autoantibody binding, thereby exacerbating lung injury after transplant. We induced emphysema in C57BL/6 mice through 6 months of cigarette smoke (CS) exposure. Mice with CS exposure had significantly elevated serum autoantibodies compared with non-smoke-exposed age-matched (NS) mice. To determine the impact of a full preexisting autoantibody repertoire on IRI, we transplanted BALB/c donor lungs into NS or CS recipients and analyzed grafts 48 hours after transplant. CS recipients had significantly increased lung injury and immune cell infiltration after transplant. Immunofluorescence staining revealed increased IgM, IgG, and C3d deposition in CS recipients. To exclude confounding alloreactivity and confirm the role of preexisting autoantibodies in IRI, syngeneic Rag1-/- (recombination-activating protein 1-knockout) transplants were performed in which recipients were reconstituted with pooled serum from CS or NS mice. Serum from CS-exposed mice significantly increased IRI compared with control mice, with trends in antibody and C3d deposition similar to those seen in allografts. These data demonstrate that pretransplant CS exposure is associated with increased IgM/IgG autoantibodies, which, upon transplant, bind to the donor lung, activate complement, and exacerbate post-transplant IRI.


Assuntos
Anticorpos/efeitos adversos , Progressão da Doença , Transplante de Pulmão/efeitos adversos , Enfisema Pulmonar/imunologia , Traumatismo por Reperfusão/etiologia , Animais , Autoanticorpos/sangue , Proteínas do Sistema Complemento/metabolismo , Epitopos/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Enfisema Pulmonar/sangue , Traumatismo por Reperfusão/sangue , Fumar
17.
Clin Transplant ; 33(10): e13695, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31421062

RESUMO

BACKGROUND: Diabetes mellitus (DM) is associated with increased post-operative complications in various surgeries. Little data exist regarding the impact of long-standing DM (>25 years) on outcomes in pancreas transplantation (PTX). The objectives of our study were to determine if long-standing pre-transplant DM (>25 years) was associated with inferior outcomes following PTX. METHODS: Using a 13-year (April, 2000-May, 2012) retrospective analysis, we examined demographic and transplant factors, complications, and outcomes in patients without (Group A) and with (Group B) long-standing (>25 years) pre-PTX DM. RESULTS: Mean follow-up was 4.2 years. Of 214 consecutive PTX performed, 137 (105 simultaneous PTX (SPK), 25 PTX after kidney (PAK), 7 PTX alone (PTA)) had pre-PTX duration of DM recorded, including 65 in Group A and 72 in Group B. There were no differences between cohorts with respect to demographics. There were no differences in post-PTX surgical/medical complications. There were no differences in outcomes between cohorts (ie, rejection, graft loss or death). CONCLUSIONS: This large-scale analysis demonstrated that PTX can be performed in patients with long-standing DM with excellent patient and graft outcomes. Long-standing DM did not lead to an increased post-PTX infections or complications. Our study suggests that duration of DM should not impact PTX candidacy.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Diabetes Mellitus Tipo 2/cirurgia , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Transplante de Pâncreas/efeitos adversos , Transplante de Pâncreas/estatística & dados numéricos , Complicações Pós-Operatórias/etiologia , Adulto , Feminino , Seguimentos , Humanos , Masculino , Transplante de Pâncreas/métodos , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
18.
J Mol Cell Cardiol ; 119: 51-63, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29680681

RESUMO

AIMS: Following an acute myocardial infarction (MI) the extracellular matrix (ECM) undergoes remodeling in order to prevent dilation of the infarct area and maintain cardiac output. Excessive and prolonged inflammation following an MI exacerbates adverse ventricular remodeling. Macrophages are an integral part of the inflammatory response that contribute to this remodeling. Treatment with histone deacetylase (HDAC) inhibitors preserves LV function and myocardial remodeling in the post-MI heart. This study tested whether inhibition of HDAC activity resulted in preserving post-MI LV function through the regulation of macrophage phenotype and early resolution of inflammation. METHODS AND RESULTS: HDAC inhibition does not affect the recruitment of CD45+ leukocytes, CD45+/CD11b+ inflammatory monocytes or CD45+/CD11b+CD86+ inflammatory macrophages for the first 3 days following infarct. Further, HDAC inhibition does not change the high expression level of the inflammatory cytokines in the first days following MI. However, by day 7, there was a significant reduction in the levels of CD45+/Cd11b+ and CD45+/CD11b+/CD86+ cells with HDAC inhibition. Remarkably, HDAC inhibition resulted in the dramatic increase in the recruitment of CD45+/CD11b+/CD206+ alternatively activated macrophages as early as 1 day which remained significantly elevated until 5 days post-MI. qRT-PCR revealed that HDAC inhibitor treatment shifts the cytokine and chemokine environment towards an M2 phenotype with upregulation of M2 markers at 1 and 5 days post-MI. Importantly, HDAC inhibition correlates with significant preservation of both LV ejection fraction and end-diastolic volume and is associated with a significant increase in micro-vessel density in the border zone at 14 days post-MI. CONCLUSION: Inhibition of HDAC activity result in the early recruitment of reparative CD45+/CD11b+/CD206+ macrophages in the post-MI heart and correlates with improved ventricular function and remodeling. This work identifies a very promising therapeutic opportunity to manage macrophage phenotype and enhance resolution of inflammation in the post-MI heart.


Assuntos
Histona Desacetilase 1/genética , Inibidores de Histona Desacetilases/administração & dosagem , Inflamação/tratamento farmacológico , Infarto do Miocárdio/tratamento farmacológico , Cicatrização/genética , Animais , Antígeno B7-2/metabolismo , Antígeno CD11b/metabolismo , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Coração/crescimento & desenvolvimento , Coração/fisiopatologia , Histona Desacetilase 1/antagonistas & inibidores , Humanos , Inflamação/genética , Inflamação/fisiopatologia , Antígenos Comuns de Leucócito/metabolismo , Leucócitos/metabolismo , Macrófagos/metabolismo , Camundongos , Monócitos/efeitos dos fármacos , Infarto do Miocárdio/genética , Infarto do Miocárdio/fisiopatologia , Neovascularização Fisiológica/genética , Remodelação Ventricular/efeitos dos fármacos , Remodelação Ventricular/genética , Cicatrização/efeitos dos fármacos
19.
Am J Transplant ; 18(10): 2417-2428, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29504277

RESUMO

Donor brain death (BD) is an inherent part of lung transplantation (LTx) and a key contributor to ischemia-reperfusion injury (IRI). Complement activation occurs as a consequence of BD in other solid organ Tx and exacerbates IRI, but the role of complement in LTx has not been investigated. Here, we investigate the utility of delivering nebulized C3a receptor antagonist (C3aRA) pretransplant to BD donor lungs in order to reduce post-LTx IRI. BD was induced in Balb/c donors, and lungs nebulized with C3aRA or vehicle 30 minutes prior to lung procurement. Lungs were then cold stored for 18 hours before transplantation into C57Bl/6 recipients. Donor lungs from living donors (LD) were removed and similarly stored. At 6 hours and 5 days post-LTx, recipients of BD donor lungs had exacerbated IRI and acute rejection (AR), respectively, compared to recipients receiving LD lungs, as determined by increased histopathological injury, immune cells, and cytokine levels. A single pretransplant nebulized dose of C3aRA to the donor significantly reduced IRI as compared to vehicle-treated BD donors, and returned IRI and AR grades to that seen following LD LTx. These data demonstrate a role for complement inhibition in the amelioration of IRI post-LTx in the context of donor BD.


Assuntos
Morte Encefálica/fisiopatologia , Rejeição de Enxerto/prevenção & controle , Transplante de Pulmão/efeitos adversos , Receptores de Complemento/antagonistas & inibidores , Traumatismo por Reperfusão/prevenção & controle , Doadores de Tecidos , Administração por Inalação , Animais , Rejeição de Enxerto/etiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão/etiologia
20.
Pediatr Transplant ; 22(5): e13218, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29761937

RESUMO

We present the unique case of a 15-month-old male born with biliary atresia and situs inversus totalis and disrupted inferior vena cava who underwent a successful liver transplantation. The patient had previously undergone a failed Kasai procedure and presented with persistent hyperbilirubinemia. The patient was transplanted with a left lateral segment donor having standard arterial anatomy. Technical considerations included identifying completely replaced arterial anatomy in the recipient from the superior mesenteric artery and creating a branch patch between the gastroduodenal artery and HA, anastomosing the donor left hepatic vein to confluences of the donor left, middle, and right hepatic veins, using a "lazy-S" configuration of portal vein anastomosis, and suspending the allograft to the abdominal wall. Post-operatively, his liver function tests and total bilirubin normalized and he progressed to tolerating an oral diet with tube-feed supplementation.


Assuntos
Anormalidades Múltiplas/cirurgia , Atresia Biliar/cirurgia , Transplante de Fígado , Situs Inversus/cirurgia , Veia Cava Inferior/anormalidades , Humanos , Lactente , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA