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1.
Clin Transplant ; 38(1): e15159, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37792580

RESUMO

Ectopic variceal bleeding is a potentially under recognized source of gastrointestinal (GI) hemorrhage. While vascular complications following pancreatic transplant are relatively common, the development of symptomatic ectopic venous varices has rarely been reported. We report two patients with a remote history of simultaneous kidney pancreas transplant (SPK) presenting two decades after transplant with an occult GI bleed. In both cases, a lengthy diagnostic course was required. The varices were treated with coil embolization via transhepatic approach. Our findings add to the limited literature on this topic and aid in the recognition, diagnosis, and management of this unusual presentation.


Assuntos
Embolização Terapêutica , Varizes Esofágicas e Gástricas , Transplante de Pâncreas , Varizes , Humanos , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/terapia , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Varizes/complicações , Varizes/terapia , Transplante de Pâncreas/efeitos adversos
2.
Am J Transplant ; 23(12): 1980-1989, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37748554

RESUMO

Older compatible living donor kidney transplant (CLDKT) recipients have higher mortality and death-censored graft failure (DCGF) compared to younger recipients. These risks may be amplified in older incompatible living donor kidney transplant (ILDKT) recipients who undergo desensitization and intense immunosuppression. In a 25-center cohort of ILDKT recipients transplanted between September 24, 1997, and December 15, 2016, we compared mortality, DCGF, delayed graft function (DGF), acute rejection (AR), and length of stay (LOS) between 234 older (age ≥60 years) and 1172 younger (age 18-59 years) recipients. To investigate whether the impact of age was different for ILDKT recipients compared to 17 542 CLDKT recipients, we used an interaction term to determine whether the relationship between posttransplant outcomes and transplant type (ILDKT vs CLDKT) was modified by age. Overall, older recipients had higher mortality (hazard ratio: 1.632.072.65, P < .001), lower DCGF (hazard ratio: 0.360.530.77, P = .001), and AR (odds ratio: 0.390.540.74, P < .001), and similar DGF (odds ratio: 0.461.032.33, P = .9) and LOS (incidence rate ratio: 0.880.981.10, P = 0.8) compared to younger recipients. The impact of age on mortality (interaction P = .052), DCGF (interaction P = .7), AR interaction P = .2), DGF (interaction P = .9), and LOS (interaction P = .5) were similar in ILDKT and CLDKT recipients. Age alone should not preclude eligibility for ILDKT.


Assuntos
Transplante de Rim , Humanos , Idoso , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Adulto , Transplante de Rim/efeitos adversos , Doadores Vivos , Sobrevivência de Enxerto , Rejeição de Enxerto/etiologia , Antígenos HLA , Fatores de Risco
3.
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
4.
Am J Transplant ; 21(4): 1612-1621, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33370502

RESUMO

Incompatible living donor kidney transplant recipients (ILDKTr) have pre-existing donor-specific antibody (DSA) that, despite desensitization, may persist or reappear with resulting consequences, including delayed graft function (DGF) and acute rejection (AR). To quantify the risk of DGF and AR in ILDKT and downstream effects, we compared 1406 ILDKTr to 17 542 compatible LDKT recipients (CLDKTr) using a 25-center cohort with novel SRTR linkage. We characterized DSA strength as positive Luminex, negative flow crossmatch (PLNF); positive flow, negative cytotoxic crossmatch (PFNC); or positive cytotoxic crossmatch (PCC). DGF occurred in 3.1% of CLDKT, 3.5% of PLNF, 5.7% of PFNC, and 7.6% of PCC recipients, which translated to higher DGF for PCC recipients (aOR = 1.03 1.682.72 ). However, the impact of DGF on mortality and DCGF risk was no higher for ILDKT than CLDKT (p interaction > .1). AR developed in 8.4% of CLDKT, 18.2% of PLNF, 21.3% of PFNC, and 21.7% of PCC recipients, which translated to higher AR (aOR PLNF = 1.45 2.093.02 ; PFNC = 1.67 2.403.46 ; PCC = 1.48 2.243.37 ). Although the impact of AR on mortality was no higher for ILDKT than CLDKT (p interaction = .1), its impact on DCGF risk was less consequential for ILDKT (aHR = 1.34 1.621.95 ) than CLDKT (aHR = 1.96 2.292.67 ) (p interaction = .004). Providers should consider these risks during preoperative counseling, and strategies to mitigate them should be considered.


Assuntos
Transplante de Rim , Função Retardada do Enxerto/etiologia , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Transplante de Rim/efeitos adversos , Doadores Vivos , Estudos Retrospectivos , Fatores de Risco
5.
Ann Surg ; 268(3): 541-549, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29994931

RESUMO

OBJECTIVE (S): Our objective was to investigate alterations in the cecal microbial composition during the development of type 1 diabetes (T1D) with or without IgM therapy, and correlate these alterations with the corresponding immune profile. METHODS: (1) Female nonobese diabetic (NOD) mice treated with IgM or saline (n = 20/group) were divided into 5-week-old nondiabetic; 9 to 12-week-old prehyperglycemic stage-1; ≥13-week-old prehyperglycemic stage-2; and diabetic groups. 16S rRNA libraries were prepared from bacterial DNA and deep-sequenced. (2) New-onset diabetic mice were treated with IgM (200 µg on Days 1, 3, and 5) and their blood glucose monitored for 2 months. RESULTS: Significant dysbiosis was observed in the cecal microbiome with the progression of T1D development. The alteration in microbiome composition was characterized by an increase in the bacteroidetes:firmicutes ratio. In contrast, IgM conserved normal bacteroidetes:firmicutes ratio and this effect was long-lasting. Furthermore, oral gavage using cecal content from IgM-treated mice significantly diminished the incidence of diabetes compared with controls, indicating that IgM specifically affected mucosa-associated microbes, and that the affect was causal and not an epiphenomenon. Also, regulatory immune cell populations (myeloid-derived suppressor cells and regulatory T cells) were expanded and insulin autoantibody production diminished in the IgM-treated mice. In addition, IgM therapy reversed hyperglycemia in 70% of new-onset diabetic mice (n = 10) and the mice remained normoglycemic for the entire post-treatment observation period. CONCLUSIONS: The cecal microbiome appears to be important in maintaining immune homeostasis and normal immune responses.


Assuntos
Ceco/microbiologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Microbioma Gastrointestinal/imunologia , Homeostase/imunologia , Imunoglobulina M/imunologia , Animais , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/terapia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD
6.
Nephrol Nurs J ; 44(2): 119-157, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29165963

RESUMO

The aims of this study were twofold: 1) to describe the post-transfer (defined as from pediatric to adult providers) incidence of predictors (medication nonadherence, acute rejection, and change in kidney function), as well as outcomes (graft loss) for adolescent and young adult kidney transplant recipients during a three-year post-transfer follow-up period; and 2) to identify variables to monitor these predictors, in the form of a clinical profile, so providers can promote early intervention for these medically at-risk adolescents. National data were used to describe predictors and outcomes for 250 youth (16 to 25 years old) three years after transfer of care. These predictors were combined with previous literature to develop a preliminary clinical profile. Using an evidence-based clinical profile with predictors for graft loss by a dedicated healthcare professional as a transition coordinator will assist in identifying those at risk for poor outcomes after transfer.


Assuntos
Transplante de Rim , Transferência de Pacientes , Adolescente , Criança , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Imunossupressores/administração & dosagem , Fatores de Risco , Transplantados
7.
Clin Immunol ; 2016 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-27989896

RESUMO

The thymus is important for the development of the immune system. However, aging leads to predictable involution of the thymus and immunodeficiency. These immunodeficiencies may be rectified with thymic rejuvenation. Atrophy of the thymus is governed by a complex interplay of molecular, cytokine and hormonal factors. Herein we review the interaction of these factors across age and how they may be targeted for thymic rejuvenation. We further discuss the growing pre-clinical evidence defining the necessary and sufficient contributions of the thymus to successful tolerance induction in transplantation.

8.
Clin Transplant ; 30(11): 1473-1479, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27623240

RESUMO

OBJECTIVE: The purpose of this study was to determine whether bacterial contamination of islets affects graft success after total pancreatectomy with islet autotransplantation (TPIAT). BACKGROUND: Factors associated with insulin independence after TPIAT are inconclusive. Although bacterial contamination does not preclude transplantation, the impact of bacterial contamination on graft success is unknown. METHODS: Patients who received TPIAT at the University of Virginia between January 2007 and January 2016 were reviewed. Patient charts were reviewed for bacterial contamination and patients were prospectively contacted to assess rates of insulin independence. RESULTS: There was no significant difference in demographic or perioperative data between patients who achieved insulin independence and those who did not. However, six of 27 patients analyzed (22.2%) grew bacterial contaminants from culture of the final islet preparations. These patients had significantly lower islet yield and C-peptide at most recent follow-up (P<.05), and none of these patients achieved insulin independence. CONCLUSIONS: Islet transplant solutions are often culture positive, likely secondary to preprocurement pancreatic manipulation and introduction of enteric flora. Although autotransplantation of culture-positive islets is safe, it is associated with higher rates of graft failure and poor islet yield. Consideration should be given to identify patients who may develop refractory chronic pancreatitis and offer early operative management to prevent bacterial colonization.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Insulina/uso terapêutico , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/microbiologia , Pancreatectomia , Pancreatite Crônica/cirurgia , Complicações Pós-Operatórias/tratamento farmacológico , Adolescente , Adulto , Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/prevenção & controle , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos , Estudos Retrospectivos , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
9.
Proc Natl Acad Sci U S A ; 110(34): 13785-90, 2013 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-23918395

RESUMO

Endothelial cells play significant roles in conditioning tissues after injury by the production and secretion of angiocrine factors. At least two distinct subsets of monocytes, CD45(+)CD11b(+)Gr1(+)Ly6C(+) inflammatory and CD45(+)CD11b(+)Gr1(-)Ly6C(-) anti-inflammatory monocytes, respond differentially to these angiocrine factors and promote pathogen/debris clearance and arteriogenesis/tissue regeneration, respectively. We demonstrate here that local sphingosine 1-phosphate receptor 3 (S1P3) agonism recruits anti-inflammatory monocytes to remodeling vessels. Poly(lactic-co-glycolic acid) thin films were used to deliver FTY720, an S1P1/3 agonist, to inflamed and ischemic tissues, which resulted in a reduction in proinflammatory cytokine secretion and an increase in regenerative cytokine secretion. The altered balance of cytokine secretion results in preferential recruitment of anti-inflammatory monocytes from circulation. The chemotaxis of these cells, which express more S1P3 than inflammatory monocytes, toward SDF-1α was also enhanced with FTY720 treatment, but not in S1P3 knockout cells. FTY720 delivery enhanced arteriolar diameter expansion and increased length density of the local vasculature. This work establishes a role for S1P receptor signaling in the local conditioning of tissues by angiocrine factors that preferentially recruit regenerative monocytes that can enhance healing outcomes, tissue regeneration, and biomaterial implant functionality.


Assuntos
Monócitos/fisiologia , Neovascularização Fisiológica/fisiologia , Propilenoglicóis/farmacologia , Próteses e Implantes/efeitos adversos , Receptores de Lisoesfingolipídeo/metabolismo , Esfingosina/análogos & derivados , Engenharia Tecidual/métodos , Lesões do Sistema Vascular/tratamento farmacológico , Análise de Variância , Animais , Western Blotting , Células Cultivadas , Quimiotaxia/efeitos dos fármacos , Citocinas/metabolismo , Primers do DNA/genética , Portadores de Fármacos , Cloridrato de Fingolimode , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Ácido Láctico , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Microvasos/citologia , Monócitos/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Propilenoglicóis/administração & dosagem , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Lisoesfingolipídeo/agonistas , Esfingosina/administração & dosagem , Esfingosina/farmacologia , Lesões do Sistema Vascular/etiologia
10.
Prog Transplant ; 26(4): 356-364, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27683424

RESUMO

BACKGROUND: Improvements in transplantation have increased the survival of children after kidney transplantation. These patients have complex needs, and the current medical system is not prepared to effectively transfer the care of these individuals from pediatric to adult health-care systems. Too often, transfer occurs during moments of crisis and is associated with poor outcomes. OBJECTIVE: The aim of this study was to use a national database, the Scientific Registry of Transplant Recipients, to test the hypothesis that the increased risk of graft loss after transfer of care (from pediatric to adult services) for young adult kidney transplant recipients over a 2- to 3-year posttransfer follow-up period was related to these posttransfer risk factors (medication noncompliance, acute rejection, insurance status). DESIGN: A retrospective, longitudinal, correlational design using secondary data was used to evaluate the transfer of care of 250 kidney transplant recipients (ages 16-25). RESULTS: Seventy-seven (30.8%) individuals lost their graft within 3 years after transfer of care. Medication noncompliance, acute rejection, and serum creatinine >2.0 mg/dL at transfer were significant predictors of graft loss after accounting for multiple other factors. CONCLUSION: These individuals are at risk for graft loss after transfer of care and may benefit from increased personalized care during this risky period.


Assuntos
Rejeição de Enxerto , Transplante de Rim , Criança , Sobrevivência de Enxerto , Humanos , Estudos Retrospectivos , Fatores de Risco
11.
Kidney Int ; 85(2): 439-49, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24025639

RESUMO

Noninvasive, cost-effective biomarkers that allow accurate monitoring of graft function are needed in kidney transplantation. Since microRNAs (miRNAs) have emerged as promising disease biomarkers, we sought to establish an miRNA signature in urinary cell pellets comparing kidney transplant patients diagnosed with chronic allograft dysfunction (CAD) with interstitial fibrosis and tubular atrophy and those recipients with normal graft function. Overall, we evaluated 191 samples from 125 deceased donor primary kidney transplant recipients in the discovery, initial validation, and the longitudinal validation studies for noninvasive monitoring of graft function. Of 1733 mature miRNAs studied using microarrays, 22 were found to be differentially expressed between groups. Ontology and pathway analyses showed inflammation as the principal biological function associated with these miRNAs. Twelve selected miRNAs were longitudinally evaluated in urine samples of an independent set of 66 patients, at two time points after kidney transplant. A subset of these miRNAs was found to be differentially expressed between groups early after kidney transplant before histological allograft injury was evident. Thus, a panel of urine miRNAs was identified as potential biomarkers for monitoring graft function and anticipating progression to CAD in kidney transplant patients.


Assuntos
Perfilação da Expressão Gênica , Testes Genéticos/métodos , Transplante de Rim , Rim/fisiopatologia , MicroRNAs/urina , Insuficiência Renal Crônica/diagnóstico , Adulto , Idoso , Atrofia , Biópsia , Estudos de Casos e Controles , Feminino , Fibrose , Marcadores Genéticos , Humanos , Rim/patologia , Transplante de Rim/efeitos adversos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Proteinúria/diagnóstico , Proteinúria/genética , Proteinúria/urina , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/urina , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento , Urinálise , Adulto Jovem
12.
J Clin Immunol ; 34 Suppl 1: S22-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24711004

RESUMO

Little is known about the function of natural IgM autoantibodies, especially that of IgM anti-leukocyte autoantibodies (IgM-ALA). Natural IgM-ALA are present at birth and characteristically increase during inflammatory and infective conditions. Our prior clinical observations and those of other investigators showing fewer rejections in renal and cardiac allografts transplanted into recipients with high levels of IgM-ALA led us to investigate whether IgM-ALA regulate the inflammatory response. In this review, we show that IgM, in physiologic doses, inhibit pro-inflammatory cell function in-vitro. We also show in an IgM knockout murine model, with intact B cells and regulatory T cells, that there is more severe inflammation and loss of function in the absence of IgM after renal ischemia reperfusion injury and cardiac allograft rejection. Replenishing IgM in IgM knockout mice or increasing the levels of IgM-ALA in wild-type B6 mice significantly attenuated the inflammation in both of these inflammatory models that involve IFN-γ and IL-17. The protective effect on renal ischemia reperfusion injury Is mediated by IgM ALA as protection was lost when using IgM pre-adsorbed with leukocytes to remove IgM-ALA. We provide data to show that the anti-inflammatory effect of IgM is mediated, in part, by inhibiting TLR-4-induced NF-κB translocation into the nucleus and inhibiting differentiation of activated T cells into Th-1 and Th-17 cells. In additional studies, we also show that intra-peritoneal administration of IgM prevents NOD mice from developing autoimmune insulitis which also involves Th-1 and Th-17 cells. These observations highlight the importance of IgM-ALA in regulating excess inflammation mediated by both innate and adaptive immune mechanisms and where the inflammatory response involves Th-17 cells that are not effectively regulated by T regs, B regs, and IL-10. IgM-ALA may in part regulate inflammation by altering dendritic cell function, as dendritic cells pre-treated in-vitro with polyclonal IgM protected mice from renal IRI. The latter findings may have relevance for cell-based therapy.


Assuntos
Autoanticorpos/imunologia , Imunoglobulina M/imunologia , Células Th17/imunologia , Imunidade Adaptativa , Animais , Humanos , Imunidade Inata , Imunoglobulina M/genética , Imunomodulação , Inflamação/imunologia , Leucócitos/imunologia , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
13.
JAMA Surg ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809546

RESUMO

Importance: A new liver allocation policy was implemented by United Network for Organ Sharing (UNOS) in February 2020 with the stated intent of improving access to liver transplant (LT). There are growing concerns nationally regarding the implications this new system may have on LT costs, as well as access to a chance for LT, which have not been captured at a multicenter level. Objective: To characterize LT volume and cost changes across the US and within specific center groups and demographics after the policy implementation. Design, Setting, and Participants: This cross-sectional study collected and reviewed LT volume from multiple centers across the US and cost data with attention to 8 specific center demographics. Two separate 12-month eras were compared, before and after the new UNOS allocation policy: March 4, 2019, to March 4, 2020, and March 5, 2020, to March 5, 2021. Data analysis was performed from May to December 2022. Main Outcomes and Measures: Center volume, changes in cost. Results: A total of 22 of 68 centers responded comparing 1948 LTs before the policy change and 1837 LTs postpolicy, resulting in a 6% volume decrease. Transplants using local donations after brain death decreased 54% (P < .001) while imported donations after brain death increased 133% (P = .003). Imported fly-outs and dry runs increased 163% (median, 19; range, 1-75, vs 50, range, 2-91; P = .009) and 33% (median, 3; range, 0-16, vs 7, range, 0-24; P = .02). Overall hospital costs increased 10.9% to a total of $46 360 176 (P = .94) for participating centers. There was a 77% fly-out cost increase postpolicy ($10 600 234; P = .03). On subanalysis, centers with decreased LT volume postpolicy observed higher overall hospital costs ($41 720 365; P = .048), and specifically, a 122% cost increase for liver imports ($6 508 480; P = .002). Transplant centers from low-income states showed a significant increase in hospital (12%) and import (94%) costs. Centers serving populations with larger proportions of racial and ethnic minority candidates and specifically Black candidates significantly increased costs by more than 90% for imported livers, fly-outs, and dry runs despite lower LT volume. Similarly, costs increased significantly (>100%) for fly-outs and dry runs in centers from worse-performing health systems. Conclusions and Relevance: Based on this large multicenter effort and contrary to current assumptions, the new liver distribution system appears to place a disproportionate burden on populations of the current LT community who already experience disparities in health care. The continuous allocation policies being promoted by UNOS could make the situation even worse.

14.
N Engl J Med ; 363(21): 2004-14, 2010 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-21083386

RESUMO

BACKGROUND: The outcomes of kidney transplantation and immunosuppression in people infected with human immunodeficiency virus (HIV) are incompletely understood. METHODS: We undertook a prospective, nonrandomized trial of kidney transplantation in HIV-infected candidates who had CD4+ T-cell counts of at least 200 per cubic millimeter and undetectable plasma HIV type 1 (HIV-1) RNA levels while being treated with a stable antiretroviral regimen. Post-transplantation management was provided in accordance with study protocols that defined prophylaxis against opportunistic infection, indications for biopsy, and acceptable approaches to immunosuppression, management of rejection, and antiretroviral therapy. RESULTS: Between November 2003 and June 2009, a total of 150 patients underwent kidney transplantation; survivors were followed for a median period of 1.7 years. Patient survival rates (±SD) at 1 year and 3 years were 94.6±2.0% and 88.2±3.8%, respectively, and the corresponding mean graft-survival rates were 90.4% and 73.7%. In general, these rates fall somewhere between those reported in the national database for older kidney-transplant recipients (≥65 years) and those reported for all kidney-transplant recipients. A multivariate proportional-hazards analysis showed that the risk of graft loss was increased among patients treated for rejection (hazard ratio, 2.8; 95% confidence interval [CI], 1.2 to 6.6; P=0.02) and those receiving antithymocyte globulin induction therapy (hazard ratio, 2.5; 95% CI, 1.1 to 5.6; P=0.03); living-donor transplants were protective (hazard ratio, 0.2; 95% CI, 0.04 to 0.8; P=0.02). A higher-than-expected rejection rate was observed, with 1-year and 3-year estimates of 31% (95% CI, 24 to 40) and 41% (95% CI, 32 to 52), respectively. HIV infection remained well controlled, with stable CD4+ T-cell counts and few HIV-associated complications. CONCLUSIONS: In this cohort of carefully selected HIV-infected patients, both patient- and graft-survival rates were high at 1 and 3 years, with no increases in complications associated with HIV infection. The unexpectedly high rejection rates are of serious concern and indicate the need for better immunotherapy. (Funded by the National Institute of Allergy and Infectious Diseases; ClinicalTrials.gov number, NCT00074386.).


Assuntos
Infecções por HIV/complicações , Terapia de Imunossupressão , Falência Renal Crônica/cirurgia , Transplante de Rim , Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Adulto , Contagem de Linfócito CD4 , Quimioprevenção , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Infecções por HIV/imunologia , Humanos , Imunossupressores/uso terapêutico , Estimativa de Kaplan-Meier , Falência Renal Crônica/etiologia , Transplante de Rim/imunologia , Transplante de Rim/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infecções Oportunistas , Modelos de Riscos Proporcionais , Transplante Homólogo
15.
Heliyon ; 9(8): e19226, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37664715

RESUMO

A life-threatening manifestation of Covid-19 infection is a cytokine storm that requires hospitalization and supplemental oxygen. Various strategies to reduce inflammatory cytokines have had some success in limiting cytokine storm and improving survival. Agonists of adenosine A2A receptors (A2AR) reduce cytokine release from most immune cells. Apadenoson is a potent and selective anti-inflammatory adenosine analog that reduces inflammation. When administered by subcutaneous osmotic pumps to mice infected with SARS CoV-2, Apadenoson was found to improve the outcomes of infection as measured by a decrease in weight loss, improved clinical symptoms, reduced levels of proinflammatory cytokines and chemokines in bronchial lavage (BAL) fluid, and enhanced survival of K18-hACE2 transgenic mice. These results support further examination of A2AR agonists as therapies for treating cytokine storm due to COVID-19.

16.
PLoS One ; 18(8): e0288920, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37566593

RESUMO

BACKGROUND: Adenosine inhibits the activation of most immune cells and platelets. Selective adenosine A2A receptor (A2AR) agonists such as regadenoson (RA) reduce inflammation in most tissues, including lungs injured by hypoxia, ischemia, transplantation, or sickle cell anemia, principally by suppressing the activation of invariant natural killer T (iNKT) cells. The anti-inflammatory effects of RA are magnified in injured tissues due to induction in immune cells of A2ARs and ecto-enzymes CD39 and CD73 that convert ATP to adenosine in the extracellular space. Here we describe the results of a five patient study designed to evaluate RA safety and to seek evidence of reduced cytokine storm in hospitalized COVID-19 patients. METHODS AND FINDINGS: Five COVID-19 patients requiring supplemental oxygen but not intubation (WHO stages 4-5) were infused IV with a loading RA dose of 5 µg/kg/h for 0.5 h followed by a maintenance dose of 1.44 µg/kg/h for 6 hours, Vital signs and arterial oxygen saturation were recorded, and blood samples were collected before, during and after RA infusion for analysis of CRP, D-dimer, circulating iNKT cell activation state and plasma levels of 13 proinflammatory cytokines. RA was devoid of serious side effects, and within 24 hours from the start of infusion was associated with increased oxygen saturation (93.8 ± 0.58 vs 96.6 ± 1.08%, P<0.05), decreased D-dimer (754 ± 17 vs 518 ± 98 ng/ml, P<0.05), and a trend toward decreased CRP (3.80 ± 1.40 vs 1.98 ± 0.74 mg/dL, P = 0.075). Circulating iNKT cells, but not conventional T cells, were highly activated in COVID-19 patients (65% vs 5% CD69+). RA infusion for 30 minutes reduced iNKT cell activation by 50% (P<0.01). RA infusion for 30 minutes did not influence plasma cytokines, but infusion for 4.5 or 24 hours reduced levels of 11 of 13 proinflammatory cytokines. In separate mouse studies, subcutaneous RA infusion from Alzet minipumps at 1.44 µg/kg/h increased 10-day survival of SARS-CoV-2-infected K18-hACE2 mice from 10 to 40% (P<0.001). CONCLUSIONS: Infused RA is safe and produces rapid anti-inflammatory effects mediated by A2A adenosine receptors on iNKT cells and possibly in part by A2ARs on other immune cells and platelets. We speculate that iNKT cells are activated by release of injury-induced glycolipid antigens and/or alarmins such as IL-33 derived from virally infected type II epithelial cells which in turn activate iNKT cells and secondarily other immune cells. Adenosine released from hypoxic tissues, or RA infused as an anti-inflammatory agent decrease proinflammatory cytokines and may be useful for treating cytokine storm in patients with Covid-19 or other inflammatory lung diseases or trauma.


Assuntos
COVID-19 , Células T Matadoras Naturais , Camundongos , Animais , COVID-19/metabolismo , Síndrome da Liberação de Citocina/tratamento farmacológico , Receptor A2A de Adenosina/metabolismo , SARS-CoV-2/metabolismo , Citocinas/metabolismo
17.
Endocr Rev ; 29(5): 603-30, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18664617

RESUMO

Although type 1 diabetes cannot be prevented or reversed, replacement of insulin production by transplantation of the pancreas or pancreatic islets represents a definitive solution. At present, transplantation can restore euglycemia, but this restoration is short-lived, requires islets from multiple donors, and necessitates lifelong immunosuppression. An emerging paradigm in transplantation and autoimmunity indicates that systemic inflammation contributes to tissue injury while disrupting immune tolerance. We identify multiple barriers to successful islet transplantation, each of which either contributes to the inflammatory state or is augmented by it. To optimize islet transplantation for diabetes reversal, we suggest that targeting these interacting barriers and the accompanying inflammation may represent an improved approach to achieve successful clinical islet transplantation by enhancing islet survival, regeneration or neogenesis potential, and tolerance induction. Overall, we consider the proinflammatory effects of important technical, immunological, and metabolic barriers including: 1) islet isolation and transplantation, including selection of implantation site; 2) recurrent autoimmunity, alloimmune rejection, and unique features of the autoimmune-prone immune system; and 3) the deranged metabolism of the islet transplant recipient. Consideration of these themes reveals that each is interrelated to and exacerbated by the other and that this connection is mediated by a systemic inflammatory state. This inflammatory state may form the central barrier to successful islet transplantation. Overall, there remains substantial promise in islet transplantation with several avenues of ongoing promising research. This review focuses on interactions between the technical, immunological, and metabolic barriers that must be overcome to optimize the success of this important therapeutic approach.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Inflamação/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Autoimunidade/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/cirurgia , Sobrevivência de Enxerto/imunologia , Humanos , Tolerância Imunológica/imunologia , Inflamação/metabolismo
18.
Ann Surg ; 256(4): 634-41, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22964733

RESUMO

OBJECTIVE: To investigate whether polyclonal serum naturally occurring immunoglobulin M (nIgM) therapy prevents the onset and progression of autoimmune diabetes and promotes islet allograft survival. BACKGROUND: nIgM deficiency is associated with an increased tendency toward autoimmune disease development. Elevated levels of nIgM anti-leukocyte autoantibodies are associated with fewer graft rejections. METHODS: Four- to five-week-old female nonobese diabetic (NOD) littermates received intraperitoneal nIgM or phosphate-buffered saline/bovine serum albumin/immunoglobulin G (100 µg followed by 50-75 µg biweekly) until 18 weeks of age. C57BL/6 recipients of 300 BALB/c or 50 C57BL/6 islet grafts received saline or nIgM. RESULTS: Eighty percent control mice (n = 30) receiving saline became diabetic by 18 to 20 weeks of age. In contrast, none of 33 of nIgM-treated mice became diabetic (P < 0.0001). Discontinuing therapy resulted in hyperglycemia in only 9 of 33 mice at 22 weeks postdiscontinuation, indicating development of ß-cell unresponsiveness. nIgM therapy initiated at 11 weeks of age resulted in hyperglycemia in only 20% of treated animals (n = 20) compared with 80% of controls (P < 0.0001). Treatment of mildly diabetic mice with nIgM (75 µg 3× per week) restored normoglycemia (n = 5), whereas severely diabetic mice required minimal dose islet transplant with nIgM to restore normoglycemia (n = 4). The mean survival time of BALB/c islet allografts transplanted in streptozotocin-induced diabetic C57BL/6 mice was 41.2 ± 3.3 days for nIgM-treated recipients (n = 4, fifth recipient remains normoglycemic) versus 10.2 ± 2.6 days for controls (n = 5) (P < 0.001). Also, after syngeneic transplantation, time taken to return to normoglycemia was 15.4 ± 3.6 days for nIgM-treated recipients (n = 5) and more than 35 days for controls (n = 4). CONCLUSIONS: nIgM therapy demonstrates potential in preventing the onset and progression of autoimmune diabetes and in promoting islet graft survival.


Assuntos
Autoanticorpos/uso terapêutico , Diabetes Mellitus Tipo 1/prevenção & controle , Sobrevivência de Enxerto , Imunoglobulina M/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Animais , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/cirurgia , Modelos Animais de Doenças , Feminino , Inflamação/etiologia , Inflamação/imunologia , Inflamação/prevenção & controle , Estimativa de Kaplan-Meier , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Complicações Pós-Operatórias/imunologia , Complicações Pós-Operatórias/prevenção & controle , Resultado do Tratamento
20.
J Surg Res ; 176(2): 629-38, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22316669

RESUMO

Our institution explored using allografts from donors with Hepatitis C virus (HCV) for elderly renal transplantation (RT). Thirteen HCV- elderly recipients were transplanted with HCV+ allografts (eD+/R-) between January 2003 and April 2009. Ninety HCV- elderly recipients of HCV- allografts (eD-/R-), eight HCV+ recipients of HCV+ allografts (D+/R+) and thirteen HCV+ recipients of HCV- allografts (D-/R+) were also transplanted. Median follow-up was 1.5 (range 0.8-5) years. Seven eD+/R- developed a positive HCV viral load and six had elevated liver transaminases with evidence of hepatitis on biopsy. Overall, eD+/R- survival was 46% while the eD-/R- survival was 85% (P = 0.003). Seven eD+/R- died during follow-up. Causes included multi-organ failure and sepsis (n = 4), cancer (n = 1), failure-to-thrive (n = 1) and surgical complications (n = 1). One eD+/R- died from causes directly related to HCV infection. In conclusion, multiple eD+/R- quickly developed HCV-related liver disease and infections were a frequent cause of morbidity and mortality.


Assuntos
Hepatite C/transmissão , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Complicações Pós-Operatórias/virologia , Adulto , Fatores Etários , Idoso , Feminino , Seguimentos , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/mortalidade , Sobrevivência de Enxerto , Hepatite C/mortalidade , Humanos , Imunossupressores/uso terapêutico , Estimativa de Kaplan-Meier , Falência Renal Crônica/mortalidade , Masculino , Pessoa de Meia-Idade , Morbidade , Complicações Pós-Operatórias/mortalidade , Doadores de Tecidos , Transplante Homólogo , Adulto Jovem
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