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3.
Am J Transplant ; 17(7): 1843-1852, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28133906

RESUMO

SIMCER was a 6-mo, multicenter, open-label trial. Selected de novo liver transplant recipients were randomized (week 4) to everolimus with low-exposure tacrolimus discontinued by month 4 (n = 93) or to tacrolimus-based therapy (n = 95), both with basiliximab induction and enteric-coated mycophenolate sodium with or without steroids. The primary end point, change in estimated GFR (eGFR; MDRD formula) from randomization to week 24 after transplant, was superior with everolimus (mean eGFR change +1.1 vs. -13.3 mL/min per 1.73 m2 for everolimus vs. tacrolimus, respectively; difference 14.3 [95% confidence interval 7.3-21.3]; p < 0.001). Mean eGFR at week 24 was 95.8 versus 76.0 mL/min per 1.73 m2 for everolimus versus tacrolimus (p < 0.001). Treatment failure (treated biopsy-proven acute rejection [BPAR; rejection activity index score >3], graft loss, or death) from randomization to week 24 was similar (everolimus 10.0%, tacrolimus 4.3%; p = 0.134). BPAR was more frequent between randomization and month 6 with everolimus (10.0% vs. 2.2%; p = 0.026); the rate of treated BPAR was 8.9% versus 2.2% (p = 0.055). Sixteen everolimus-treated patients (17.8%) and three tacrolimus-treated patients (3.2%) discontinued the study drug because of adverse events. In conclusion, early introduction of everolimus at an adequate exposure level with gradual calcineurin inhibitor (CNI) withdrawal after liver transplantation, supported by induction therapy and mycophenolic acid, is associated with a significant renal benefit versus CNI-based immunosuppression but more frequent BPAR.


Assuntos
Everolimo/farmacologia , Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/farmacologia , Transplante de Fígado/efeitos adversos , Ácido Micofenólico/farmacologia , Tacrolimo/farmacologia , Feminino , Seguimentos , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Estudos Prospectivos , Fatores de Risco
4.
Clin Res Hepatol Gastroenterol ; 40(6): 660-665, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27288298

RESUMO

Regulatory T cells (Treg) may play an important role in operational (clinical) tolerance (OT), a stable graft function without immunosuppression in an otherwise immunocompetent host, that is spontaneously observed in some patients many years after transplantation. Several ongoing clinical trials are currently testing the effects of donor-specific or non-specific Treg infusion with the goal to induce this state of OT a few months after liver transplantation (LT). The preliminary results of two of these trials have been recently published, and raise a number of comments and issues: (1) These two papers demonstrate that a 100 to 1000-fold ex-vivo expansion of Treg is possible in humans after 2 weeks of culture. The optimal human Treg dose is however not clearly established, and might be higher than the dose that would be expected from translating murine data. (2) A lot of concerns are remaining regarding the Treg purity before expansion, the Treg stability during in vitro culture and the in vivo fate of infused cells. A strict monitoring of Treg should thus be done at each step. (3) Since Treg may play a detrimental role in some conditions, such as viral diseases and cancer, potential LT recipients with such diseases should probably be excluded from the initial trials of Treg infusion. (4) The follow-up of tolerant liver recipients should include repeated liver biopsies and detection of autoantibodies and humoral response, in addition to conventional liver graft assessment, in order to prevent the development of immune complications related to immunosuppression withdrawal. (5) The final issue raised by Treg therapy in LT is the choice of the immunosuppressive regimen used before tapering or withdrawal, appropriate to preserve OT establishment.


Assuntos
Imunoterapia/métodos , Transplante de Fígado , Linfócitos T Reguladores/citologia , Células Cultivadas , Ensaios Clínicos como Assunto , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/farmacologia
5.
Transplant Proc ; 44(9): 2834-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23146536

RESUMO

BACKGROUND: Inevitable hepatitis C virus recurrence after liver transplantation, a major barrier to survival of the transplanted liver may be promoted by immunosuppression and by CD4(+)CD25(+) regulatory T cells (Treg). Treg cells are essential for the induction and maintenance of immunologic self-tolerance as well as transplant tolerance. Moreover, we have previously described low doses of cyclosporine (CsA) to inhibit Treg activity by inducing interleukin-2 and interfron-γ. We investigated here in, the effect of mycophenolate mofetil (MMF) and corticosteroids, usually used in combination with a calcineurin inhibitor on human CD4(+)CD25(+) Treg cells. METHODS: Human CD4(+)CD25(+) cells isolated from healthy donors were cultured in the presence of CsA +/- corticoids or MMF. Suppressive activity of regulatory T cells was assessed in mixed leukocyte reactions including CD25(+) solvents with autologous activated peripheral blood mononuclear cells (PBMC). RESULTS: MMF and dexamethasone inhibited PBMC and Treg proliferation in dose-dependent fashing, maintaining the suppressive activity of Treg cells. However, the association of corticoids with CsA could not reverse the inhibitory effects of CsA on Treg activity, unlike the MMF and CsA combination. CONCLUSION: We have previously shown CsA to significantly impair the function of CD4(+)CD25(+) Treg cells. Herein we reports that corticoids were not able to reverse this effect, whereas MMF couterbalanced it, suggesting that the combination of MMF with CsA maintains regulatory T cells activity promoting tolerance.


Assuntos
Corticosteroides/farmacologia , Ciclosporina/farmacologia , Dexametasona/farmacologia , Imunossupressores/farmacologia , Ácido Micofenólico/análogos & derivados , Linfócitos T Reguladores/efeitos dos fármacos , Biomarcadores/metabolismo , Calcineurina/metabolismo , Inibidores de Calcineurina , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Humanos , Tolerância Imunológica/efeitos dos fármacos , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Teste de Cultura Mista de Linfócitos , Ácido Micofenólico/farmacologia , Linfócitos T Reguladores/imunologia
6.
Am J Transplant ; 11(5): 965-76, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21466650

RESUMO

We conducted a multicenter randomized study in liver transplantation to compare standard-dose tacrolimus to reduced-dose tacrolimus with mycophenolate mofetil to reduce the occurrence of tacrolimus side effects. Two primary outcomes (censored criteria) were monitored during 48 weeks post-transplantation: occurrence of renal dysfunction or arterial hypertension or diabetes (evaluating benefit) and occurrence of acute graft rejection (evaluating risk). Interim analyses were performed every 40 patients to stop the study in the case of increased risk of graft rejection. One hundred and ninety-five patients (control: 100; experimental: 95) had been included when the study was stopped. Acute graft rejection occurred in 46 (46%) and 28 (30%) patients in control and experimental groups, respectively (HR = 0.59; 95% CI: [0.37-0.94]; p = 0.024). Renal dysfunction or arterial hypertension or diabetes occurred in 80 (80%) and 61 (64%) patients in control and experimental groups, respectively (HR = 0.68; 95% CI: [0.49-0.95]; p = 0.021). Renal dysfunction occurred in 42 (42%) and 23 (24%) patients in control and experimental groups, respectively (HR = 0.49; 95% CI: [0.29-0.81]; p = 0.004). Leucopoenia (p = 0.001), thrombocytopenia (p = 0.017) and diarrhea (p = 0.002) occurred more frequently in the experimental group. Reduced-dose tacrolimus with mycophenolate mofetil reduces the occurrence of renal dysfunction and the risk of graft rejection. This immunosuppressive regimen could replace full-dose tacrolimus in adult liver transplantation.


Assuntos
Imunossupressores/administração & dosagem , Transplante de Fígado/métodos , Ácido Micofenólico/análogos & derivados , Tacrolimo/administração & dosagem , Adulto , Complicações do Diabetes/imunologia , Diarreia/induzido quimicamente , Relação Dose-Resposta a Droga , Feminino , França , Rejeição de Enxerto/prevenção & controle , Humanos , Hipertensão/etiologia , Rim/fisiopatologia , Leucopenia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/administração & dosagem , Estudos Prospectivos , Trombocitopenia/induzido quimicamente , Resultado do Tratamento
7.
Transplant Proc ; 42(10): 4343-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21168695

RESUMO

BACKGROUND: Hepatic fibrosis, an outcome of chronic liver diseases, is characterized by an accumulation of collagen, which is produced by activated human intrahepatic fibroblasts (HIF). Transforming growth factor (TGF) ß is an important inducer of fibrogenesis, in collaboration with other cytokines, such as interleukin (IL) 4. IL-4 is overexpressed in severe recurrent hepatitis C after liver transplantation, exerting profibrotic effects. In contrast, cyclosporine (CsA) had been shown to decrease fibroblast activation and collagen production. We therefore investigated the effects of CsA on TGF-ß and IL-4 profibrotic activities on HIF in vitro. METHODS: Isolated HIF were cultured without or with human TGF-ß, human IL-4, CsA, or combined TGF- ß+CsA or IL-4+CsA. We performed real-time polymerase chain reaction for collagen types I, III, and IV and alpha-SMA, a marker of fibroblast activation we also measured total collagen in supernates. TGF-ß and IL-4 increased the expressions of alpha smooth muscle action (SMA) collagen I, III, and IV mRNAs (P < .05 vs untreated cells) as well as the overall collagen level in the supernates (P < .01). CsA decreased the expression of mRNAs encoding alpha-SMA and collagens (P < .01). Expressions of alpha-SMA and collagens I, III, and IV mRNAs were significantly lower under combined treatments (TGF-ß vs TGF-ß+CsA [P < .01] and IL-4 vs IL-4+CsA [P < .01]). Collagen level was decreased by combined treatments (TGF-ß vs TGF-ß+CsA [P < .05] and IL-4 vs IL-4+CsA [P = .05]). CONCLUSION: CsA inhibited the profibrotic effects of TGF-ß and IL-4 by decreasing the activation and production of collagen by HIF. CsA may decrease fibroblast activation and collagen accumulation, exerting beneficial effects on fibrosis progression, particularly among patients with recurrent hepatitis C.


Assuntos
Ciclosporina/farmacologia , Interleucina-4/antagonistas & inibidores , Fígado/efeitos dos fármacos , Fator de Crescimento Transformador beta/antagonistas & inibidores , Células Cultivadas , Colágeno/genética , Fibroblastos/efeitos dos fármacos , Fibrose , Humanos , Técnicas In Vitro , Interleucina-4/farmacologia , Fígado/citologia , Fator de Crescimento Transformador beta/farmacologia
9.
Gastroenterol Clin Biol ; 33 Suppl 4: S247-52, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20004330

RESUMO

The safety and tolerability of everolimus has been evaluated in a randomized, phase II trial, comparing 3 doses of everolimus to a placebo, in association with cyclosporine and corticosteroids, after liver transplantation. There were no significant differences between groups in the rates of the composite end point (graft failure, biopsy-proven acute rejection, graft loss, death, or loss to follow-up) or its individual components. Although there were lower rates of treated acute rejection and mortality with the higher dosages (2 and 4 mg/day), these did not reach statistical significance. Interestingly, freedom from rejection correlated with trough blood levels of everolimus: patients with levels of 3 ng/mL or less had rejection rates 3-fold higher than patients with levels exceeding 3 ng/mL. All graft losses and most deaths were associated with typical posttransplant complications, not with study medication and not due to hepatic artery thrombosis. There were no clear dose-related differences among groups for hematology parameters. After transplantation, renal function declined to a similar extent in all 4 groups. The overall incidence of infection was comparable between groups (61-77%). Although the interpretation of the results of this trial is hampered by the small sample sizes of patient groups (about 30 in each group) and the high dropout rates (about 50%), this study suggests that everolimus is an effective immunosuppressive agent with an acceptable patient tolerance and safety profile after liver transplantation.


Assuntos
Imunossupressores/administração & dosagem , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Transplante de Fígado/métodos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Sirolimo/análogos & derivados , Ciclosporina/administração & dosagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Everolimo , Rejeição de Enxerto/epidemiologia , Humanos , Transplante de Fígado/mortalidade , Placebos , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Serina-Treonina Quinases TOR
10.
Am J Transplant ; 9(9): 2102-12, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19624566

RESUMO

Immune response failure during HCV infection has been associated with the activity of regulatory T cells. Hepatitis C-related cirrhosis is the main reason for liver transplantation. However, 80% of transplanted patients present an accelerated recurrence of the disease. This study assessed the involvement of regulatory T-cell subsets (CD4+CD25+ cells: 'Treg' and CD49b+CD18+ cells: 'T regulatory-1' cells), in the recurrence of HCV after liver transplantation, using transcriptomic analysis, ELISA assays on serum samples and immunohistochemistry on liver biopsies from liver recipients 1 and 5 years after transplantation. Three groups of patients were included: stable HCV-negative recipients and those with mild and severe hepatitis C recurrence. At 5 years, Treg markers were overexpressed in all HCV+ recipients. By contrast, Tr1 markers were only overexpressed in patients with severe recurrence. At 1 year, a trend toward the overexpression of Tr1 was noted in patients evolving toward severe recurrence. IL-10 production, a characteristic of the Tr1 subset, was enhanced in severe recurrence at both 1 and 5 years. These results suggest that Tr1 are enhanced during severe HCV recurrence after liver transplantation and could be predictive of HCV recurrence. High levels of IL-10 at 1 year could be predictive of severe recurrence, and high IL-10 producers might warrant more intensive management.


Assuntos
Regulação Viral da Expressão Gênica , Hepatite C/imunologia , Transplante de Fígado/métodos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Adulto , Antígenos CD18/biossíntese , Linfócitos T CD4-Positivos/imunologia , Feminino , Hepatite C/metabolismo , Humanos , Integrina alfa2/biossíntese , Interleucina-10/biossíntese , Subunidade alfa de Receptor de Interleucina-2/biossíntese , Masculino , Pessoa de Meia-Idade , Recidiva
11.
Am J Transplant ; 9(8): 1946-52, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19519819

RESUMO

Solid organ transplantations (SOT) are performed successfully in selected HIV-infected patients. However, multiple and reciprocal drug-drug interactions are observed between antiretroviral (ARV) drugs and calcineurin inhibitors (CNIs) through CYP450 metabolization. Raltegravir (RAL), a novel HIV-1 integrase inhibitor, is not a substrate of CYP450 enzymes. We retrospectively reviewed the outcomes of 13 HIV-infected transplant patients treated by an RAL + two nucleosidic reverse transcriptase inhibitor (NRTI) regimen, in terms of tolerability, ARV efficacy (plasma viral load, CD4 cell count), drug interactions, RAL pharmacokinetics and transplant outcome. Thirteen patients with liver (n = 8) or kidney (n = 5) transplantation were included. RAL was initiated (400 mg BID) either at time of transplantation (n = 6), or after transplantation (n = 7). Median RAL trough concentration was 507 ng/mL (176-890), which is above the in vitro IC95 for wild type HIV-1 strains (15 ng/mL). Target trough levels of CNIs were promptly obtained with standard dosages of tacrolimus or cyclosporine. RAL tolerability was excellent. There was no episode of acute rejection. HIV infection remained controlled. After a median follow-up of 9 months (range: 6-14), all patients were alive with satisfactory graft function. The use of an RAL + two NRTI-based regimen is a good alternative in HIV-infected patients undergoing SOT.


Assuntos
Rejeição de Enxerto/prevenção & controle , Infecções por HIV/tratamento farmacológico , Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Transplante de Fígado/imunologia , Pirrolidinonas/efeitos adversos , Pirrolidinonas/uso terapêutico , Adulto , Antirretrovirais/uso terapêutico , Inibidores de Calcineurina , Ciclosporina/uso terapêutico , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Rejeição de Enxerto/imunologia , Integrase de HIV/efeitos dos fármacos , Integrase de HIV/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Pirrolidinonas/farmacologia , Raltegravir Potássico , Estudos Retrospectivos , Tacrolimo/uso terapêutico , Resultado do Tratamento
12.
Transplant Proc ; 41(2): 679-81, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19328955

RESUMO

Noninvasive liver fibrosis scores are evaluated in hepatitis C virus-infected patients but are less known in liver transplant recipients. Fibrosis is a frequent, multifactorial event in these patients. This preliminary retrospective study reviewed the diagnostic performance of 3 simple scores for liver fibrosis in transplant patients: namely, APRI (aspartate aminotransferase to platelet ratio index), FORNS (platelets, gamma-glutamyltransferase, patient age, and cholesterol), and FIB-4 (patient age, aspartate aminotransferase, alanine aminotransferase, and platelets). Ninety-four biopsies were collected from 50 liver transplant recipients at a mean period after orthotopic liver transplantation (OLT) of 30.7 months (range, 12-108 months). The indications for OLT were hepatitis C in 23% of cases, hepatitis B in 14%, alcoholic disease in 33%, cholestatic disease in 19%, and others in 11%. According to the Metavir classification, 72% of biopsies revealed no significant histological fibrosis (F0-1 = group 1) and 28% showed significant fibrosis (F2-4 = group 2). A correlation was observed between the histological stage of fibrosis and albumin, gamma-glutamyltransferase, aspartate aminotransferase, alanine aminotransferase, and hyaluronic acid levels. APRI and FIB-4 correlated significantly with the histological stage of fibrosis both globally and in the subgroup of nonhepatitis C liver recipients. When APRI and FIB-4 tests were applied to predict fibrosis (area under the receiver operating characteristic curve), the results were 0.87 and 0.78, respectively. Values were not significant with the FORNS test. In conclusion, APRI and FIB-4 enabled accurate prediction of significant fibrosis after OLT. In the nonhepatitis C subgroup, we found similar predictive performances. These simple scores may be applied in clinical practice in the context of follow-up after OLT independent of hepatitis C status.


Assuntos
Cirrose Hepática/epidemiologia , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Adulto , Idoso , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Biópsia , Colesterol/sangue , Feminino , Humanos , Cirrose Hepática/sangue , Transplante de Fígado/patologia , Transplante de Fígado/fisiologia , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Valor Preditivo dos Testes , Estudos Retrospectivos , Sobreviventes , Doadores de Tecidos/estatística & dados numéricos , Adulto Jovem , gama-Glutamiltransferase/sangue
13.
Transplant Proc ; 41(2): 682-4, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19328956

RESUMO

Tumor markers are elevated in a variety of nonneoplastic clinical situations, including liver diseases. Their sensitivity and specificity are lower for tumor screening in these cases. In this study, we investigated the frequency and significance of elevated tumor markers in the pre-orthotopic liver transplantation (OLT) evaluation among patients with end-stage liver disease who did not develop tumors after a long follow-up post-OLT. We performed a retrospective analysis of clinical and biological parameters of 100 OLT candidates comparing data for CA 125, CA 19-9, CA 15-3, and carcinoembryonic antigen (CEA) levels. CA 125, CA 19-9, CA 15-3, and CEA levels were elevated in 59%, 53%, 29%, and 28% of cases, respectively. CA 125, CA 15-3, and CEA were associated with disease severity (Child-Pugh classification). CA 125 was also elevated among patients with ascites, esophageal varices, or alcohol-related cirrhosis. Elevated CA 19-9 levels were associated with increased CA 15-3 and CEA levels. CA 15-3 levels were also increased among patients with elevated alkaline phosphatase, while elevated CEA was related to ascites, bilirubin, and prothrombin time (PT) levels, as well as alcohol-related cirrhosis. There was no association between hepatocellular carcinoma and tumor markers. In conclusion, CA 125, CA 19-9, CA 15-3, and CEA were frequently elevated among end-stage liver disease patients. These elevations were not associated with tumor diseases in this population.


Assuntos
Biomarcadores Tumorais/sangue , Antígeno Ca-125/sangue , Antígeno CA-19-9/sangue , Antígeno Carcinoembrionário/sangue , Cirrose Hepática Alcoólica/epidemiologia , Falência Hepática/epidemiologia , Transplante de Fígado/fisiologia , Mucina-1/sangue , Ascite/sangue , Ascite/epidemiologia , Varizes Esofágicas e Gástricas/sangue , Varizes Esofágicas e Gástricas/epidemiologia , Humanos , Cirrose Hepática Alcoólica/sangue , Falência Hepática/sangue , Estudos Retrospectivos
14.
Transpl Infect Dis ; 11(1): 83-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18803616

RESUMO

Microsporidiosis first came to prominence as an opportunistic infection in patients with acquired immunodeficiency syndrome. Microsporidia are now emerging pathogens responsible for severe diarrhea during solid organ transplantation. Two main clinical entities can be identified: infection by Enterocytozoon bieneusi, causing diarrhea with limited treatment options; and infection by Encephalitozoon intestinalis, which may disseminate and usually responds to albendazole treatment. We describe here 2 cases of microsporidiosis caused by E. bieneusi in a renal and a liver transplant recipient, respectively, in whom complete clinical efficacy of a short course of fumagillin therapy was obtained. Long-term microbiological eradication was assessed using classical methods and monitored using a real-time quantitative polymerase chain reaction-based method. Both patients experienced drug-induced thrombocytopenia, which resolved after withdrawal of the treatment. We also review the 18 other previously reported cases of microsporidiosis in transplant recipients. In case of persistent diarrhea in solid organ transplant patients, microsporidiosis should be considered. Based on the present experience, treating E. bieneusi infection with 7 days of fumagillin therapy is adequate to eradicate E. bieneusi in this context.


Assuntos
Cicloexanos/uso terapêutico , Enterocytozoon/efeitos dos fármacos , Ácidos Graxos Insaturados/uso terapêutico , Transplante de Rim/efeitos adversos , Transplante de Fígado/efeitos adversos , Microsporidiose/tratamento farmacológico , Animais , Humanos , Masculino , Microsporidiose/microbiologia , Pessoa de Meia-Idade , Sesquiterpenos/uso terapêutico , Resultado do Tratamento
15.
Med Mal Infect ; 39(4): 225-33, 2009 Apr.
Artigo em Francês | MEDLINE | ID: mdl-19111416

RESUMO

Progress in transplantation technique has offered a growing number of solid organ transplant recipients the opportunity to travel to tropical and low-income countries. The issue of vaccine-preventable diseases is a challenging question in immunocompromised patients including those with solid organ transplant. Since the response to vaccines is weakened in case of chronic organ failure, candidates should be vaccinated early in the course of the disease. Clinicians should implement a vaccinal strategy until the patient is scheduled for transplantation and monitor its efficacy by serological assays. Live attenuated vaccines (such as yellow fever, measles-mumps-rubella, or chicken pox) are contra-indicated in solid organ transplant recipients and, when indicated, should be administered prior to transplantation, particularly in foreign-born patients highly likely to visit friends and relatives in endemic areas. Vaccinations for transplant recipients considering international travel should be realized according to the risk of acquiring vaccine-preventable diseases but also on both tolerance and immune response which are affected by degree and duration of immunosuppression, comorbidities, and type of organ transplanted. Routine and specific vaccinations for solid organ transplant recipients, as well as travel-related vaccination (such as hepatitis A, typhoid, meningococcal meningitis, rabies, tick-born encephalitis, Japanese encephalitis, and cholera) should be considered during a specific pretravel medical consultation. However, vaccination should be avoided in the 6 months following transplantation when patients are usually receiving the highest doses of immunosuppressive drugs. In this comprehensive review, we provide vaccination schedules based on published studies and guidelines for vaccination of solid organ transplant recipients.


Assuntos
Transplante de Órgãos , Viagem , Vacinas , Adulto , Humanos
17.
J Viral Hepat ; 13(9): 633-42, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16907851

RESUMO

Alcohol consumption has a major impact on the natural history of chronic hepatitis C virus (HCV) infection, although the underlying mechanisms are still debated. We designed a clinical study to evaluate the impact of alcohol abuse on both viral load and expression of low-density lipoprotein receptor (LDLR) and CD81 expression. Thirty-eight consecutive HCV-infected patients were enrolled. Group 1 (n = 18), < or =10 g alcohol/day, group 2 (n = 8), < or =30 g alcohol/day, group 3 (n = 12), >or =30 g alcohol/day. Receptors expression was measured by flow cytometry analysis in peripheral blood mononuclear cells (PBMC) and by specific real-time retrotranscription polymerase chain reaction (RT-PCR) in the liver. Serum viral load was evaluated by quantification of both HCV genomic RNA and total core antigen. The hepatic viral load was assessed by real-time RT-PCR. Serum HCV-RNA and total core antigen were significantly correlated, and were higher, albeit not significantly, in group 3 than in group 1. Alcohol consumption had no effect on expression of HCV putative receptors in PBMC, except for CD81, which was upregulated on monocytes in group 2. In the liver, viral load and levels of LDLR transcripts were significantly higher in group 3 than in group 1. Remarkably, a significant positive correlation was found between LDLR transcripts and HCV-RNA (r2 = 0.83, P < 10(-3)). Finally, in vitro experiments suggested that the effect of ethanol on LDLR expression was indirectly mediated by both tumour necrosis factor-alpha and interleukin-1beta. In conclusion, this study is the first to support a role for LDLR in the natural infection by HCV in man.


Assuntos
Consumo de Bebidas Alcoólicas , Hepacivirus/fisiologia , Hepatite C Crônica/metabolismo , Hepatite C Crônica/virologia , Fígado/virologia , RNA Viral/análise , Receptores de LDL/genética , Adulto , Antígenos CD/biossíntese , Antígenos CD/genética , Citometria de Fluxo , Perfilação da Expressão Gênica , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/genética , Humanos , Leucócitos Mononucleares/química , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Receptores de LDL/biossíntese , Receptores Virais/genética , Receptores Virais/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estatística como Assunto , Tetraspanina 28 , Transcrição Gênica , Carga Viral
18.
Leukemia ; 18(10): 1711-6, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15284859

RESUMO

A link between chronic hepatitis C virus (HCV) infection and low-grade B-cell lymphomas has been suggested by epidemiological studies. Marginal zone lymphomas (MZLs) including splenic lymphomas with villous lymphocytes are among the most frequently reported subgroups in the setting of chronic HCV infection. In this study, we examined the effect of antiviral treatment in eight patients with HCV-associated MZL. We found that five out of eight patients have responded to interferon alpha and ribavirin. In some cases, hematologic responses were correlated to virologic responses. In addition, we report a case of large granular lymphocyte leukemia occurring in association with MZL and HCV, and responding to interferon and ribavirin. We suggest that there is an etiologic link between HCV and antigen-driven lymphoproliferative disorders.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/patogenicidade , Hepatite C/tratamento farmacológico , Linfoma de Células B/virologia , Adulto , Idoso , Quimioterapia Combinada , Feminino , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C/complicações , Hepatite C/virologia , Humanos , Interferon-alfa/uso terapêutico , Linfoma de Células B/complicações , Linfoma de Células B/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Ribavirina/uso terapêutico , Resultado do Tratamento
19.
Ann Dermatol Venereol ; 131(12): 1085-91, 2004 Dec.
Artigo em Francês | MEDLINE | ID: mdl-15692444

RESUMO

BACKGROUND: Post-transplantation lymphoproliferative disorders develop in 1 to 10p. 100 of organ transplant recipients and are frequently associated with Epstein-Barr virus (EBV). Among post-transplantation lymphoproliferative disorders, plasmacytoma with cutaneous involvement is exceptional. Association with EBV has been rarely reported in post-transplantation plasmacytomas and the latency type of EBV has never been characterized. We report 2 new cases of cutaneous monotype EBV-related plasmacytomas. CASE-REPORTS: Clinical presentation was a sub-cutaneous tumor on the thigh in the first case and an ulcerated nodule of the leg in the second case, occurring respectively 7 and 8 years after organ transplantation (liver transplantation and heart transplantation). In both lesions, tumor cells exhibited lambda light chain restriction and the association with EBV was confirmed using immunohistochemistry and in situ hybridization. The expression of EBV genes in tumor cells demonstrated type III latency. DISCUSSION: The classification of post-transplantation lymphoproliferative disorders is not well defined and some authors retain 3 categories. Among the latter, plasmacytomas have been rarely described. Cutaneous involvement is reported in 4 cases and an association with EBV in only 2 cases without description of viral latency. Clinical and histological features of post-transplantation plasmacytomas appear polymorphic. We report EBV-association in both cases, with a type III latency clearly demonstrated in one case, as has been reported in other lymphoproliferative diseases in patients with congenital or acquired immunodeficiency. We also discuss various possible therapeutic strategies for post-transplantation lymphoproliferative disorders.


Assuntos
Infecções por Vírus Epstein-Barr/etiologia , Transplante de Coração/efeitos adversos , Transplante de Fígado/efeitos adversos , Plasmocitoma/virologia , Neoplasias Cutâneas/virologia , Infecções por Vírus Epstein-Barr/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Plasmocitoma/etiologia , Neoplasias Cutâneas/etiologia
20.
Xenotransplantation ; 10(3): 267-77, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12694547

RESUMO

BACKGROUND: Hyperacute rejection (HAR) of discordant xenografts in the pig-to-human combination can be prevented using tranplants expressing transgenic molecules that inhibit human complement. Hypodermin A (HA), a serine esterase that degrades C3, was tested in the guinea-pig-to-rat and in the pig-to-human combinations. METHODS: Hypodermin A was tested in vitro, ex vivo, and in vivo models of HAR in the guinea-pig-to-rat combination. Hamster ovary cells (CHO) and a line of porcine aortic endothelial cells (PAEC11) were transfected with HA complementary DNA (cDNA). RESULTS: The pattern of degradation of rat and human C3 by HA was different (multiple bands lower than 40 kDa) from the physiologic pattern observed after spontaneous degradation of rat C3 or physiologic activation of human C3. The CH50 activity in serum was significantly lower in rats treated with 3.2 mg HA/kg than in untreated rats (45 +/- 16 U/ml vs. 700 +/- 63 U/ml, P < 0.05). Sera from rats injected with 3.2 mg/kg of HA were less effective in lysing guinea-pig endothelial cells (12 +/- 7%) than normal rat sera (79 +/- 3%; P < 0.001). Ex vivo, guinea-pig hearts perfused by rat serum supplemented with HA survived longer than those perfused by non-treated serum (210 +/- 34 and 154 +/- 71 min, respectively; P < 0.05). In vivo, guinea-pig hearts transplanted into HA treated rats survived longer than in non-treated rats (27 +/- 5 min vs. 13 +/- 4 min; P < 0.001). In the presence of human serum, smaller amounts of C6 and C5b-9 were deposited onto HA-transfected CHO cells than onto control cells. The mHA-PAEC11 cells were significantly more resistant to lysis by human C than control PAEC11 cells. CONCLUSIONS: These data suggest that transgenic HA could be used to prevent hyperacute xenogeneic rejection.


Assuntos
Proteínas Inativadoras do Complemento/farmacologia , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/imunologia , Serina Endopeptidases/farmacologia , Transplante Heterólogo/imunologia , Doença Aguda , Sequência de Aminoácidos , Animais , Células CHO , Sobrevivência Celular , Complemento C3/metabolismo , Complemento C6/metabolismo , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Cricetinae , Endotélio Vascular/citologia , Sobrevivência de Enxerto/imunologia , Humanos , Dados de Sequência Molecular , Ratos , Serina Endopeptidases/química , Serina Endopeptidases/isolamento & purificação , Suínos , Transfecção
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