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2.
Am J Kidney Dis ; 83(3): 329-339, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37741608

RESUMO

RATIONALE & OBJECTIVE: Outcomes of kidney transplantation for patients with renal AA amyloidosis are uncertain, with reports of poor survival and high rates of disease recurrence. However, the data are inconclusive and mostly based on studies from the early 2000s and earlier. STUDY DESIGN: Retrospective multicenter cohort study. SETTING & PARTICIPANTS: We searched the French national transplant database to identify all patients with renal AA amyloidosis who underwent kidney transplantation between 2008 and 2018. EXPOSURES: Age, cause of amyloidosis, use of biotherapies, and C-reactive protein levels. OUTCOMES: Outcomes were all-cause mortality and allograft loss. We also reported amyloidosis allograft recurrence, occurrence of acute rejection episodes, as well as infectious, cardiovascular, and neoplastic disease events. ANALYTICAL APPROACH: Kaplan-Meier estimator for mortality and cumulative incidence function method for allograft loss. Factors associated with patient and allograft survival were investigated using a Cox proportional hazards model and a cause-specific hazards model, respectively. RESULTS: 86 patients who received kidney transplants for AA amyloidosis at 26 French centers were included. The median age was 49.4 years (IQR, 39.7-61.1). The main cause of amyloidosis was familial Mediterranean fever (37 cases; 43%). 16 (18.6%) patients received biotherapy after transplantation. Patient survival rates were 94.0% (95% CI, 89.1-99.2) at 1 year and 85.5% (77.8-94.0) at 5 years after transplantation. Cumulative incidences of allograft loss were 10.5% (4.0-17.0) at 1 year and 13.0% (5.8-20.1) at 5 years after transplantation. Histologically proven AA amyloidosis recurrence occurred in 5 transplants (5.8%). An infection requiring hospitalization developed in 55.8% of cases, and there was a 27.9% incidence of acute allograft rejection. Multivariable analysis showed that C-reactive protein concentration at the time of transplantation was associated with patient survival (HR, 1.01; 95% CI, 1.00-1.02; P=0.01) and allograft survival (HR, 1.68; 95% CI, 1.10-2.57; P=0.02). LIMITATIONS: The study lacked a control group, and the effect of biotherapies on transplantation outcomes could not be explored. CONCLUSIONS: This relatively contemporary cohort of patients who received a kidney transplant for AA amyloidosis experienced favorable rates of survival and lower recurrence rates than previously reported. These data support the practice of treating these patients with kidney transplantation for end-stage kidney disease. PLAIN-LANGUAGE SUMMARY: AA amyloidosis is a severe and rare disease. Kidney involvement is frequent and leads to end-stage kidney disease. Because of the involvement of other organs, these patients are often frail, which has raised concerns about their suitability for kidney transplantation. We reviewed all patients with AA amyloidosis nephropathy who underwent kidney transplantation in France in the recent era (2008-2018) and found that the outcomes after kidney transplantation were favorable, with 85.5% of patients still alive 5 years after transplantation, a survival rate that is comparable to the outcomes of patients receiving a transplant for other forms of kidney diseases. Recurrence of amyloidosis in the transplanted kidney was infrequent (5.8%). These data support the practice of kidney transplantation for patients with AA amyloidosis who experience kidney failure.


Assuntos
Amiloidose , Nefropatias , Falência Renal Crônica , Transplante de Rim , Humanos , Pessoa de Meia-Idade , Transplante de Rim/métodos , Estudos de Coortes , Proteína C-Reativa , Estudos Retrospectivos , Amiloidose/cirurgia , Amiloidose/complicações , Falência Renal Crônica/cirurgia , Falência Renal Crônica/complicações , Nefropatias/etiologia , Estudos Multicêntricos como Assunto , Proteína Amiloide A Sérica
3.
Expert Rev Anti Infect Ther ; 21(2): 143-148, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36625025

RESUMO

INTRODUCTION: Hepatitis E Virus (HEV) was initially thought to cause only acute infections, but the discovery of chronic hepatitis E in immunocompromised patients has profoundly changed our understanding of the virus. AREAS COVERED: We describe the physiopathology, diagnosis, and clinical management of chronic HEV infection. The virus can persist in nearly two-thirds of immunosuppressed patients. Reducing immunosuppression is the first immunomodulatory strategy to cure chronic hepatitis E. But this may not always be feasible or effective. Ribavirin monotherapy for 3 months has been recommended as first-line treatment for chronically infected patients. Ribavirin is around 80% effective at eradicating HEV in retrospective studies. Apart from ribavirin, interferon has been successfully used in liver transplants recipients, but if the patient does not respond, no other alternative drug is available. The vaccine available to prevent HEV infection is one available only in China. EXPERT OPINION: HEV infection is a major concern in immunocompromised patients. But the therapeutic arsenal is limited to ribavirin and interferon. Both produce several side effects and new drugs are urgently needed. Moreover, preventive strategies to limit HEV transmission and/or evolution to a chronic infection are also required.


Assuntos
Vírus da Hepatite E , Hepatite E , Humanos , Hepatite E/diagnóstico , Hepatite E/tratamento farmacológico , Hepatite E/prevenção & controle , Ribavirina/uso terapêutico , Antivirais/uso terapêutico , Infecção Persistente , Estudos Retrospectivos , Interferons , Hospedeiro Imunocomprometido
4.
J Transl Autoimmun ; 7: 100223, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38162455

RESUMO

Bacterial recombinant cysteine protease Ides (imlifidase, Idefirix®, Hansa Biopharma) is used to prevent humoral transplant rejection in highly HLA-sensitized recipients, and to control IgG-mediated autoimmune diseases. We report the case of a 51 years old woman suffering from lupus nephritis with end stage kidney disease, grafted for the second time and pre-treated with imlifidase. The patient was HLA-hypersensitized (calculated Panel Reactive Antibodies [Abs], cPRA>99 %) and has three preformed Donor Specific Antibodies (DSA). Circulating immunoglobulins were monitored at initiation (0, 6, 36, 72 and 96 h), and at Ab recovery one and two months following imlifidase injection. From baseline, the higher depletion was reported after 36h for total IgG (-75 %) and IgG subclasses (-87 % for IgG1, IgG2 and IgG3, -78 % for IgG4), while no significant impact on IgA and IgM was observed. Anti-SSA 60 kDa and anti-SSB auto-Abs quickly decreased after imlifidase injection (-96 % for both after 36 h) as well as post-vaccinal specific IgG (-95 % for tetanus toxoid, -97 % for pneumococcus and -91 % for Haemophilus influenzae Abs after 36 h). At the Ab recovery phase, total IgG and anti-SSA60/SSB Abs reached their initial level at two months. Regarding alloreactive Abs, anti-HLA Abs including the three DSA showed a dramatic decrease after injection with 100 % depletion from baseline after 36 h as assessed by multiplex single bead antigen assay, leading to negative crossmatches using both lymphocytotoxicity (LCT) and flow cell techniques. DSA rebound at recovery was absent and remained under the positivity threshold (MFI = 1000) after 6 months. The findings from this case report are that imlifidase exerts an early depleting effect on all circulating IgG, while IgG recovery may depend in part from imlifidase's capacity to target memory B cells.

5.
J Clin Med ; 9(2)2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31991629

RESUMO

Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis throughout the world. Most infections are acute but they can become chronic in immunocompromised patients, such as solid organ transplant patients, patients with hematologic malignancy undergoing chemotherapy and those with a human immunodeficiency virus (HIV) infection. Extra-hepatic manifestations, especially neurological and renal diseases, have also been described. To date, four main genotypes of HEV (HEV1-4) were described. HEV1 and HEV2 only infect humans, while HEV3 and HEV4 can infect both humans and animals, like pigs, wild boar, deer and rabbits. The real epidemiology of HEV has been underestimated because most infections are asymptomatic. This review focuses on the recent advances in our understanding of the pathophysiology of acute HEV infections, including severe hepatitis in patients with pre-existing liver disease and pregnant women. It also examines the mechanisms leading to chronic infection in immunocompromised patients and extra-hepatic manifestations. Acute infections are usually self-limiting and do not require antiviral treatment. Conversely, a chronic HEV infection can be cleared by decreasing the dose of immunosuppressive drugs or by treating with ribavirin for 3 months. Nevertheless, new drugs are needed for those cases in which ribavirin treatment fails.

6.
Gut ; 69(5): 901-910, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31727684

RESUMO

OBJECTIVE: Hepatitis E virus (HEV), one of the most common agent of acute hepatitis worldwide, is mainly transmitted enterically, via contaminated water for HEV genotypes 1 (HEV1) and HEV2, or by eating raw or undercooked infected meat for HEV genotype 3 (HEV3) and HEV4. However, little is known about how the ingested HEV reaches the liver or its ability to replicate in intestinal cells. DESIGN: We developed human primary cultures of small intestine epithelial cells and intestinal explants obtained from small bowel resections. The epithelial cells were also polarised on transwells. Cells were infected with Kernow-p6 strain or clinically derived virions. RESULTS: Primary intestinal cells supported the growth of Kernow-p6 strain and HEV1 and HEV3 clinically derived virions. Polarised enterocytes infected with HEV1 and HEV3 strains released HEV particles vectorially: mostly into the apical compartment with a little basally. Iodixanol density gradient centrifugation of enterocyte-derived HEV virions gave bands at a density of 1.06-1.08 g/cm3, corresponding to that of quasi-enveloped HEV particles. Ribavirin therapy inhibited HEV excretion from the basal surface but not from the apical side of infected human enterocytes. HEV virions also infected intestinal tissue explants. Lastly, HEV RNA and antigen were detected in the intestinal crypts of a chronically infected patient. CONCLUSION: HEV can replicate in intestinal cells and reaches the liver as quasi-enveloped virions.


Assuntos
Vírus da Hepatite E/genética , RNA Viral/genética , Ribavirina/farmacologia , Replicação Viral/genética , Células Cultivadas , Células Epiteliais , Genótipo , Hepatócitos/efeitos dos fármacos , Hepatócitos/virologia , Humanos , Intestino Delgado/citologia , Sensibilidade e Especificidade
7.
J Virol ; 93(4)2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30463960

RESUMO

Hepatitis E virus (HEV) is a common cause of acute viral hepatitis worldwide. Most HEV infections are asymptomatic, but immunocompromised patients infected with HEV genotype 3 (HEV3), HEV4, or HEV7 may develop chronic infections. The HEV particles in stools are naked (nHEV), while those in the serum and culture supernatants (eHEV) are associated with lipids. Hepatocytes are polarized epithelial cells that have basolateral (oriented toward the blood) and apical (oriented toward the bile) exosomal pathways. We isolated a subclone, F2, from the human hepatocarcinoma cell line HepG2/C3A that grew as a polarized monolayer culture and had better HEV production than HepG2/C3A cells. F2 cells cultured on semipermeable collagen inserts and infected basolaterally with nHEV3 released 94.6% of virus particles apically, those infected with eHEV3 released 96.8% apically, and eHEV1-infected cells released 99.3% apically. Transcytosis was not involved. Density gradient centrifugation and NP-40 treatment showed that HEV particles released both apically and basolaterally were lipid associated. The apically released HEV3 and HEV1 particles were six and nine times more infectious than those released basolaterally, respectively. Confocal microscopy indicated that the open reading frame 2 (ORF2) capsid protein colocalized apically with ORF3 virus protein, the apical marker DPP4, and the recycling endosome GTPase Rab27a. The amounts of soluble glycosylated ORF2 secreted apically and basolaterally were similar. These polarized-hepatocyte data suggest that infectious HEV particles are mainly released into bile, while the small fraction released into blood could spread HEV throughout the host.IMPORTANCE Hepatitis E virus (HEV) in stools is naked, while that in culture supernatants and patients' blood is lipid associated. Its life cycle in hepatocytes, polarized cells with a basolateral side communicating with blood and an apical side connected with bile, is incompletely understood. We have developed a polarized hepatocyte model and used the cells to analyze the supernatants bathing the apical and basolateral sides and HEV subcellular distribution. HEV particles from both sides were lipid associated, and most infectious HEV particles left the cell via its apical side. Similar amounts of the open reading frame 2 (ORF2) soluble capsid protein were secreted from both sides of the hepatocytes. This model mimicking physiological conditions should help clarify the HEV cell cycle in polarized hepatocytes.


Assuntos
Vírus da Hepatite E/metabolismo , Hepatócitos/virologia , Liberação de Vírus/fisiologia , Proteínas do Capsídeo/metabolismo , Carcinoma Hepatocelular/metabolismo , Técnicas de Cultura de Células , Linhagem Celular , Polaridade Celular , Células Epiteliais/virologia , Células Hep G2 , Hepatite E/virologia , Vírus da Hepatite E/patogenicidade , Vírus da Hepatite E/fisiologia , Hepatócitos/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Soro/virologia , Proteínas Virais
8.
Virologie (Montrouge) ; 22(5): 239-250, 2018 10 01.
Artigo em Francês | MEDLINE | ID: mdl-33111685

RESUMO

Hepatitis E virus (HEV) presents a worldwide distribution. In developing countries, hepatitis E, related to HEV1 and HEV2, is a waterborne disease. In developed countries, hepatitis E is a zoonotic disease due to HEV3 and HEV4. It is mainly transmitted through meat consumption from animal reservoirs such as pig, boar, deer and rabbit. New clinical forms include neurological manifestations that are now clearly associated with HEV3 infection. Recent studies showed that ORF1 polyprotein was able to disrupt the innate immune response. It was also shown that ORF2 protein exists at least in two forms: a free, glycosylated form and a non-glycosylated form, which assembles to form the capsid. Lastly, it was shown that ORF3 protein, involved in the virus egress, acts as a viroporin. New culture systems and animal models have been developed recently, and will be very helpful to complete our understanding of HEV life cycle and pathogenesis.

9.
Transpl Infect Dis ; 19(4)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28509330

RESUMO

BACKGROUND: Malignancies and lymphoma are common complications after kidney transplantation. However, no link has been made between the incidence of malignancies and hepatitis C virus (HCV) infection in this setting. This case-controlled study compared the incidence of malignancies, including lymphoma, between kidney transplant (KT) patients with or without HCV replication. PATIENTS AND METHODS: A total of 99 HCV-positive RNA-positive KT patients were matched with 198 (1:2) anti-HCV-negative patients according to age, gender, and date of transplantation, and were followed for 145.8±78.4 months. RESULTS: During the follow-up period, 28 HCV-positive (28%) cases developed at least one cancer, and 64 (32%) patients developed cancer in the HCV-negative group (P=not significant [ns]). Survival without a cancer was similar between both groups. Thirteen HCV-positive patients (13%) developed at least one solid cancer vs 29 (15%) HCV-negative patients (P=ns). Survival without a solid cancer was similar between both groups. Three patients from the HCV-positive and 4 from the HCV-negative group developed a lymphoma. Only 2 patients from the HCV group died from hepatocellular carcinoma. Survival without a skin cancer was similar between both groups. Patient and death-censored graft survival rates were significantly lower in the HCV group. CONCLUSION: The incidences and types of malignancies were similar in the HCV-positive and HCV-negative KT patients.


Assuntos
Carcinoma Hepatocelular/complicações , Hepacivirus/isolamento & purificação , Hepatite C/epidemiologia , Transplante de Rim/efeitos adversos , Linfoma/epidemiologia , Neoplasias/epidemiologia , Adulto , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , Feminino , Sobrevivência de Enxerto , Hepatite C/complicações , Hepatite C/mortalidade , Hepatite C/virologia , Humanos , Incidência , Linfoma/complicações , Linfoma/mortalidade , Linfoma/virologia , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/mortalidade , Neoplasias/virologia , Transplantados
10.
J Clin Virol ; 79: 61-67, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27092855

RESUMO

BACKGROUND: In vitro and retrospective studies of kidney-transplant patients have shown that quinolones can efficiently prevent BK virus (BKV) replication. However, in a prospective study, a 3 month-course of levofloxacin did not decrease the rate of BK viruria in kidney-transplant patients treated with standard immunosuppression. OBJECTIVES: The aim of this study was to assess the effect of a 3-month course of ciprofloxacin prophylaxis on BKV replication in kidney-transplant patients that had received heavy immunosuppression (plasma exchange or immunoadsorption and rituximab) to achieve desensitization before undergoing HLA- and/or ABO-incompatible (ABOi) transplantation. STUDY DESIGN: Twenty-nine patients were given ciprofloxacin (500mg/d) for 3 months, starting immediately after transplantation. The results were compared with results from a previous study where patients had received a similar immunosuppression regimen without ciprofloxacin prophylaxis (n=43). Around 60% of patients had undergone a retransplantation. After transplantation, all patients were given induction therapy, tacrolimus, mycophenolic acid and steroids. BK viruria and viremia were monitored at months 1, 3, 6 and 12 post-transplantation. RESULTS: The rates of BK viruria, BK viremia, and BKV-associated nephropathy did not differ between patients who were given or not given ciprofloxacin prophylaxis. These rates were also identical when patients received quinolones at any time within the first year after transplantation compared to those that had not. The rate of bacterial infection was also similar in patients who had or had not received ciprofloxacin. CONCLUSION: The use of quinolones seemed to not have any beneficial effect in preventing BKV replication in kidney-transplant patients receiving heavy immunosuppression.


Assuntos
Antivirais/administração & dosagem , Vírus BK/crescimento & desenvolvimento , Quimioprevenção/métodos , Ciprofloxacina/administração & dosagem , Imunossupressores/uso terapêutico , Transplantados , Replicação Viral , Vírus BK/fisiologia , Humanos , Transplante de Rim , Resultado do Tratamento
11.
Expert Rev Clin Pharmacol ; 9(2): 215-27, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26691282

RESUMO

End-stage renal disease is a major health problem worldwide, with kidney transplantation being the treatment of choice. Calcineurin inhibitors are still the cornerstone of immunosuppressive therapy. However, they have well-known nephrotoxic affects and increase the risk of cardiovascular disease and cancer. In contrast, belatacept is a biological immunosuppressive agent that inhibits the T-cell co-stimulation. It is approved by the US Food and Drug Administration and the European Medicine Agency for use in adult kidney-transplant recipients to prevent acute rejection. Developmental studies show that belatacept is as efficient as calcineurin inhibitors at preventing acute rejection. In addition, kidney function is better and cardiovascular risk factors are reduced in patients given belatacept. Herein, the authors review the published evidence concerning the efficacy and safety of belatacept and discuss its potential specific indications.


Assuntos
Abatacepte/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Transplante de Rim/métodos , Abatacepte/efeitos adversos , Adulto , Animais , Inibidores de Calcineurina/efeitos adversos , Inibidores de Calcineurina/uso terapêutico , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Falência Renal Crônica/cirurgia , Transplantados
12.
J Org Chem ; 71(17): 6670-3, 2006 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-16901169

RESUMO

Starting from commercially available (+)-sclareolide, the first synthesis of zerumin B was achieved by a concise, highly efficient pathway featuring stereoselective addition of a new silyloxyfuryltitanium reagent to an aldehyde intermediate and silyloxyfuran oxyfunctionalization as key steps. The synthesis established the relative and absolute configuration of zerumin B along with its identity with a purportedly new diterpenoid isolated from the plant Renealmia alpinia.


Assuntos
Antineoplásicos/química , Antineoplásicos/síntese química , Diterpenos/síntese química , Lactonas/síntese química , Terpenos/química , Terpenos/síntese química , Aldeídos/química , Diterpenos/química , Lactonas/química , Estrutura Molecular , Estereoisomerismo , Zingiberaceae/química
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