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1.
Pancreatology ; 24(4): 545-552, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38693039

RESUMO

BACKGROUND/OBJECTIVES: No simple, accurate diagnostic tests exist for exocrine pancreatic insufficiency (EPI), and EPI remains underdiagnosed in chronic pancreatitis (CP). We sought to develop a digital screening tool to assist clinicians to predict EPI in patients with definite CP. METHODS: This was a retrospective case-control study of patients with definite CP with/without EPI. Overall, 49 candidate predictor variables were utilized to train a Classification and Regression Tree (CART) model to rank all predictors and select a parsimonious set of predictors for EPI status. Five-fold cross-validation was used to assess generalizability, and the full CART model was compared with 4 additional predictive models. EPI misclassification rate (mRate) served as primary endpoint metric. RESULTS: 274 patients with definite CP from 6 pancreatitis centers across the United States were included, of which 58 % had EPI based on predetermined criteria. The optimal CART decision tree included 10 variables. The mRate without/with 5-fold cross-validation of the CART was 0.153 (training error) and 0.314 (prediction error), and the area under the receiver operating characteristic curve was 0.889 and 0.682, respectively. Sensitivity and specificity without/with 5-fold cross-validation was 0.888/0.789 and 0.794/0.535, respectively. A trained second CART without pancreas imaging variables (n = 6), yielded 8 variables. Training error/prediction error was 0.190/0.351; sensitivity was 0.869/0.650, and specificity was 0.728/0.649, each without/with 5-fold cross-validation. CONCLUSION: We developed two CART models that were integrated into one digital screening tool to assess for EPI in patients with definite CP and with two to six input variables needed for predicting EPI status.


Assuntos
Insuficiência Pancreática Exócrina , Pancreatite Crônica , Humanos , Pancreatite Crônica/complicações , Pancreatite Crônica/diagnóstico , Insuficiência Pancreática Exócrina/diagnóstico , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos de Casos e Controles , Adulto , Idoso , Sensibilidade e Especificidade
2.
Clin Transplant ; 37(4): e14926, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36752566

RESUMO

Our previous Multicenter Trial to Transplant HCV-infected Kidneys (MYTHIC) observed that 100% of hepatitis C virus (HCV)-uninfected patients who received a kidney from an HCV-infected deceased donor were cured of HCV with an 8-week regimen of glecaprevir and pibrentasvir (G/P) initiated 2-5 days after transplantation. Following acute and chronic infection with HCV, immune system perturbations have been reported to persist even after viral clearance. The aim of this study was to determine whether HCV viremic kidney recipients in the MYTHIC study experience sustained changes in the soluble inflammatory milieu associated with HCV infection. Among nine patients with HCV viremia at day 3 post-kidney transplant (post-KT D3), IP-10, IL-10, MIP-1ß, and IL-8 were significantly elevated from baseline. However, over the subsequent visits, there was a rapid, dramatic reduction back to baseline levels. Among seven patients who were not HCV viremic at post-KT D3, the cytokine levels did not significantly change. HCV-uninfected patients who received a kidney from an HCV-viremic deceased donor and were treated with early G/P experienced only transient alterations in the soluble inflammatory milieu. These data provide reassuring evidence that there appear to be no persistent cytokine disturbances with transient HCV viremia accompanying HCV donor positive/recipient negative kidney transplant.


Assuntos
Hepatite C Crônica , Hepatite C , Humanos , Hepacivirus , Viremia , Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Rim , Doadores de Tecidos , Citocinas
3.
Kidney Int Rep ; 7(2): 241-250, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35155863

RESUMO

INTRODUCTION: Transplanting kidneys from hepatitis C virus (HCV) viremic donors into HCV-negative patients (HCV D-RNA-positive/R-negative) has evolved from experimental to "standard-of-care" at many centers. Nevertheless, most data derive from single centers and provide only short-term follow-up. METHODS: The Multicenter Study to Transplant Hepatitis C-Infected Kidneys (MYTHIC) study was a multicenter (7 sites) trial of HCV D-RNA-positive/R-negative kidney transplantation (KT) followed by 8 weeks of glecaprevir/pibrentasvir (G/P) initiated 2 to 5 days post-KT. Prespecified outcomes included probability of KT (vs. matched waitlist comparators) and 1-year safety outcomes, allograft function, and survival. RESULTS: Among 63 enrolled patients, 1-year cumulative incidence of KT was approximately 3.5-fold greater for the MYTHIC cohort versus 2055 matched United Network for Organ Sharing (UNOS) comparators who did not opt-in to receive a kidney from an HCV-viremic donor (68% vs. 19%, P < 0.0001). Of 30 HCV D-RNA-positive/R-negative KT recipients, all achieved HCV cure. None developed clinically significant liver disease or HCV-related kidney injury. Furthermore, 1-year survival was 93% and 1-year graft function was excellent (median creatinine 1.17; interquartile range [IQR]: 1.02-1.38 mg/dl). There were 4 cases of cytomegalovirus (CMV) disease among 10 CMV-negative patients transplanted with a kidney from an HCV-viremic/CMV-positive donor. CONCLUSION: The 1-year findings from this multicenter trial suggest that opting-in for HCV-viremic KT offers can increase probability of KT with excellent 1-year outcomes. Trial Registration: NCT03781726.

4.
J Hepatol ; 75(4): 820-828, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34023351

RESUMO

BACKGROUND & AIMS: Retreatment with glecaprevir/pibrentasvir (G/P) resulted in a rate of sustained virologic response 12 weeks after treatment completion (SVR12) of >90% in HCV genotype 1 (GT1) patients who previously failed a regimen of sofosbuvir plus an NS5A inhibitor (NS5Ai). This study investigated the prevalence and impact of baseline NS3 and NS5A resistance-associated substitutions (RASs) on the efficacy of G/P in prior GT1 sofosbuvir+NS5Ai failures and the persistence of treatment-emergent RASs. METHODS: Longitudinal samples from 177 patients enrolled in a phase IIIb, randomized pragmatic clinical trial were analyzed. Patients without cirrhosis were randomized to 12 or 16 weeks of G/P, and patients with compensated cirrhosis were randomized to G/P and ribavirin for 12 weeks or G/P for 16 weeks. Linkage of RAS was identified using Primer-ID next-generation sequencing at a 15% cut-off. RESULTS: Of 177 patients, 169 (95.5%) were PI-naïve. All 33 GT1b-infected patients achieved SVR12. In GT1a-infected patients, baseline NS5A RASs were prevalent (74.5%, 105/141) but NS3 RASs were uncommon. Baseline NS3 RASs had no impact on G/P efficacy and patients with baseline NS5A RASs showed a numerically but not statistically significantly lower SVR12 rate compared to those without NS5A RASs (89% vs. 97%). SVR12 was achieved in 34 of 35 (97%) patients without NS5A baseline substitution, and 53 of 57 (93%), 35 of 40 (88%), 5 of 8 (63%) with single, double-linked, and triple-linked NS5A substitutions, respectively. Among 13 patients with virologic failure, 4 acquired treatment-emergent NS3 RASs and 10 acquired NS5A RASs. CONCLUSION: Baseline NS5A RASs were highly prevalent. The presence of an increasing number of linked NS5A RASs in GT1a showed a trend in decreasing SVR12 rates, although no specific NS5A RASs or their linkage pattern were associated with lower SVR12 rates. LAY SUMMARY: Direct-acting antivirals have revolutionized the treatment of chronic hepatitis C infection, but treatment failure occurs in some patients. Retreatment of patients who previously failed a regimen consisting of sofosbuvir and an NS5A inhibitor with a regimen of glecaprevir and pibrentasvir (G/P) is >90% effective. Herein, we analyzed samples from these patients and showed that retreatment efficacy with G/P is lower in patients with double- or triple-linked NS5A resistance mutations than in patients with single or no NS5A resistance mutations. CLINICAL TRIAL NUMBER: NCT03092375.


Assuntos
Benzimidazóis/farmacologia , Resistência a Medicamentos/imunologia , Pirrolidinas/farmacologia , Quinoxalinas/farmacologia , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Sofosbuvir/metabolismo , Sulfonamidas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Adulto , Antivirais/administração & dosagem , Antivirais/metabolismo , Benzimidazóis/uso terapêutico , Combinação de Medicamentos , Feminino , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C/fisiopatologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pirrolidinas/uso terapêutico , Quinoxalinas/administração & dosagem , Quinoxalinas/uso terapêutico , RNA Polimerase Dependente de RNA/farmacologia , Sofosbuvir/administração & dosagem , Sulfonamidas/uso terapêutico , Estados Unidos/epidemiologia , Proteínas não Estruturais Virais/farmacologia
5.
J Am Soc Nephrol ; 31(11): 2678-2687, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32843477

RESUMO

BACKGROUND: Single-center trials and retrospective case series have reported promising outcomes using kidneys from donors with hepatitis C virus (HCV) infection. However, multicenter trials are needed to determine if those findings are generalizable. METHODS: We conducted a prospective trial at seven centers to transplant 30 kidneys from deceased donors with HCV viremia into HCV-uninfected recipients, followed by 8 weeks of once-daily coformulated glecaprevir and pibrentasvir, targeted to start 3 days posttransplant. Key outcomes included sustained virologic response (undetectable HCV RNA 12 weeks after completing treatment with glecaprevir and pibrentasvir), adverse events, and allograft function. RESULTS: We screened 76 patients and enrolled 63 patients, of whom 30 underwent kidney transplantation from an HCV-viremic deceased donor (median kidney donor profile index, 53%) in May 2019 through October 2019. The median time between consent and transplantation of a kidney from an HCV-viremic donor was 6.3 weeks. All 30 recipients achieved a sustained virologic response. One recipient died of complications of sepsis 4 months after achieving a sustained virologic response. No severe adverse events in any patient were deemed likely related to HCV infection or treatment with glecaprevir and pibrentasvir. Three recipients developed acute cellular rejection, which was borderline in one case. Three recipients developed polyomavirus (BK) viremia near or >10,000 copies/ml that resolved after reduction of immunosuppression. All recipients had good allograft function, with a median creatinine of 1.2 mg/dl and median eGFR of 57 ml/min per 1.73 m2 at 6 months. CONCLUSIONS: Our multicenter trial demonstrated safety and efficacy of transplantation of 30 HCV-viremic kidneys into HCV-negative recipients, followed by early initiation of an 8-week regimen of glecaprevir and pibrentasvir.


Assuntos
Ácidos Aminoisobutíricos/uso terapêutico , Antivirais/uso terapêutico , Benzimidazóis/uso terapêutico , Ciclopropanos/uso terapêutico , Hepacivirus , Hepatite C/prevenção & controle , Transplante de Rim , Lactamas Macrocíclicas/uso terapêutico , Leucina/análogos & derivados , Prolina/análogos & derivados , Quinoxalinas/uso terapêutico , RNA Viral/sangue , Sulfonamidas/uso terapêutico , Adulto , Aloenxertos/fisiologia , Aloenxertos/virologia , Ácidos Aminoisobutíricos/efeitos adversos , Antivirais/efeitos adversos , Benzimidazóis/efeitos adversos , Ciclopropanos/efeitos adversos , Combinação de Medicamentos , Feminino , Taxa de Filtração Glomerular , Hepatite C/sangue , Humanos , Rim/fisiologia , Lactamas Macrocíclicas/efeitos adversos , Leucina/efeitos adversos , Leucina/uso terapêutico , Masculino , Prolina/efeitos adversos , Prolina/uso terapêutico , Estudos Prospectivos , Pirrolidinas , Quinoxalinas/efeitos adversos , Sulfonamidas/efeitos adversos , Resposta Viral Sustentada
6.
Gastroenterology ; 157(6): 1506-1517.e1, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31401140

RESUMO

BACKGROUND & AIMS: Treatment options are limited for patients with hepatitis C (HCV) infection with treatment failure after sofosbuvir plus an NS5A inhibitor. There are some data for the efficacy of glecaprevir/pibrentasvir (G/P) in these patients. We performed a randomized trial of the safety and efficacy of 12 and 16 weeks of G/P, with or without ribavirin, in patients with HCV genotype 1 infection with treatment failure after sofosbuvir and an NS5A inhibitor. METHODS: We performed a phase 3b, open-label study of patients with chronic HCV genotype 1 infection who received previous treatment with sofosbuvir plus an NS5A inhibitor. Patients without cirrhosis were randomly assigned to groups that received G/P for 12 weeks (n = 78, group A) or 16 weeks (n = 49, group B). Patients with compensated cirrhosis were randomly assigned to groups that received G/P and ribavirin for 12 weeks (n = 21, group C) or G/P for 16 weeks (n = 29, group D). The primary end point was a sustained virologic response 12 weeks after treatment. Samples collected at baseline and at time of treatment failure were sequenced for resistance-associated substitutions in NS3 and NS5A. RESULTS: Of the 177 patients in the 4 groups, 81% were men, 79% had HCV genotype 1a infection, and 44% were black. Proportions of patients with sustained virologic response 12 weeks after treatment in groups A, B, C, and D were 90%, 94%, 86%, and 97%, respectively. The treatment failed in 13 (7.3%) patients with HCV genotype 1a infection, 6 (7.9%) in group A, 3 (6.1%) in group B, 3 (6.1%) in group C (6.1%), and 1 (3.4%) in group D. Most patients had baseline resistance-associated substitutions in NS5A. Treatment-emergent resistance-associated substitutions in NS3 and NS5A were observed in 9 and 10 patients with treatment failure, respectively. G/P was well tolerated. Ribavirin increased adverse events but did not increase efficacy. CONCLUSIONS: In a randomized study of patients with chronic HCV genotype 1 infection who received previous treatment with sofosbuvir plus an NS5A inhibitor, 16 weeks treatment with G/P produced sustained virologic response 12 weeks after treatment in >90% of patients, including those with compensated cirrhosis. ClinicalTrials.gov, Number: NCT03092375.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antivirais/farmacologia , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Combinação de Medicamentos , Farmacorresistência Viral Múltipla/genética , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Pirrolidinas/farmacologia , Pirrolidinas/uso terapêutico , Quinoxalinas/farmacologia , Quinoxalinas/uso terapêutico , Ribavirina/farmacologia , Ribavirina/uso terapêutico , Sofosbuvir/farmacologia , Sofosbuvir/uso terapêutico , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Resposta Viral Sustentada , Falha de Tratamento , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/genética
7.
Lancet Infect Dis ; 17(10): 1062-1068, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28818546

RESUMO

BACKGROUND: The once-daily, ribavirin-free, pangenotypic, direct-acting antiviral regimen, glecaprevir coformulated with pibrentasvir, has shown high rates of sustained virological response in phase 2 and 3 studies. We aimed to assess the efficacy and safety of 12 weeks of coformulated glecaprevir and pibrentasvir in patients with hepatitis C virus (HCV) infection and compensated cirrhosis. METHODS: We did this single-arm, open-label, multicentre phase 3 study at 40 sites in Belgium, Canada, Germany, South Africa, Spain, and the USA. We enrolled patients aged 18 years or older with HCV genotype 1, 2, 4, 5, or 6 infection and compensated cirrhosis. Patients were either HCV treatment-naive or had not responded to treatment with interferon or pegylated interferon with or without ribavirin, or sofosbuvir plus ribavirin with or without pegylated interferon. Oral glecaprevir (300 mg) coformulated with pibrentasvir (120 mg) was administered once daily for 12 weeks. The primary efficacy endpoint was sustained virological response at post-treatment week 12 (HCV RNA <15 IU/mL). We assessed efficacy and safety in all patients who received at least one dose of study drug (intention-to-treat population). This study is registered with ClinicalTrials.gov, number NCT02642432. FINDINGS: Between Dec 7, 2015, and May 4, 2016, we enrolled 146 patients with compensated cirrhosis, of whom 48 (33%) had genotype 1a HCV infection, 39 (27%) had genotype 1b infection, 34 (23%) had genotype 2 infection, 16 (11%) had genotype 4 infection, two (1%) had genotype 5 infection, and seven (5%) had genotype 6 infection. 12 weeks after treatment, 145 patients (99%, 95% CI 98-100) achieved sustained virological response, with one (1%) relapse at post-treatment week 8. We recorded 101 (69%) adverse events, of which 65 (64%) were mild. The most common adverse events were fatigue (n=28 [19%]) and headache (n=20 [14%]). 11 (8%) patients had serious adverse events, none of which were deemed related to study drugs. No patients had elevations in alanine aminotransferase and no patients prematurely discontinued treatment because of adverse events. INTERPRETATION: Our results show that 99% of patients treated with once-daily glecaprevir plus pibrentasvir achieved a sustained virological response at 12 weeks. Furthermore, this drug regimen had a favourable safety profile in previously treated or untreated patients with chronic HCV genotype 1, 2, 4, 5, or 6 infection and compensated cirrhosis. These findings could help simplify treatment algorithms and reduce treatment burden. FUNDING: AbbVie.


Assuntos
Benzimidazóis/uso terapêutico , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Cirrose Hepática/complicações , Quinoxalinas/uso terapêutico , Sulfonamidas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácidos Aminoisobutíricos , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Benzimidazóis/administração & dosagem , Ciclopropanos , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/classificação , Humanos , Lactamas Macrocíclicas , Leucina/análogos & derivados , Masculino , Pessoa de Meia-Idade , Prolina/análogos & derivados , Pirrolidinas , Quinoxalinas/administração & dosagem , Sulfonamidas/administração & dosagem
8.
Lung ; 193(1): 3-11, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25318864

RESUMO

PURPOSE: The objective of this study is to compare how likely positive tuberculin skin test (TST) and T-SPOT(®).TB (TSPOT) results predict risk factors for tuberculosis in a predominantly immigrant patient population at risk of latent TB infection (LTBI) and with rheumatologic conditions requiring immunomodulatory therapy (IMT). METHODS: Prospective study conducted at a referral rheumatology clinic. Inclusion criteria included patients on various IMT, including immunosuppressive drugs that could predispose to TB progression. We studied risk factors associated with LTBI, test results, and tests' agreement. RESULTS: We studied 101 patients. Eighty (79.2 %) were from countries where TB is prevalent and Bacille Calmette-Guérin vaccination is placed routinely. Seventy-four (73.3 %) had rheumatoid arthritis and 92 (90.7 %) were on IMT. Among patients with both TST and TSPOT results, 25 (30.9 %) were TST(+) and 20 (24.7 %) had TSPOT(+) results. Fifteen patients (18.5 %) had TST(+)/TSPOT(+) results, and 51 (63.0 %) had TST(-)/TSPOT(-) results (agreement = 81.5 %; kappa = .54 [95 % CI, .34-.74; P < .001]). Each TSPOT(+) and TST(+) results were independently associated with immigrant status and prior residence in a TB prevalent country after adjustment for immunosuppressive therapy: Adjusted OR(TSPOT+)=6.6 (95 % CI, 1.2-123.3; P = .027); and adjusted OR(TST+)=11.2 (95 % CI, 2.0-209.5; P = .003). Seven out of 10 TST(+)/TSPOT(-) cases had a TST ≥15 mm induration, including three cases with history of TST conversion. CONCLUSIONS: TST(+) and TSPOT(+) results predict risk factors associated with LTBI independent of immunosuppressive IMT. Some TST(+)/TSPOT(-) results were unlikely to be false-negatives. The combined use of TST and TSPOT appears to be a reasonable diagnostic strategy to evaluate for LTBI in this population.


Assuntos
Emigrantes e Imigrantes , ELISPOT , Imunossupressores/uso terapêutico , Tuberculose Latente/diagnóstico , Doenças Reumáticas/tratamento farmacológico , Reações Falso-Negativas , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Tuberculose Latente/epidemiologia , Tuberculose Latente/imunologia , Minnesota/epidemiologia , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Doenças Reumáticas/diagnóstico , Doenças Reumáticas/epidemiologia , Doenças Reumáticas/imunologia , Medição de Risco , Fatores de Risco , Teste Tuberculínico
10.
Curr HIV Res ; 9(4): 237-46, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21671884

RESUMO

The use of HIV protease inhibitors (PIs) as part of antiretroviral therapy in the treatment of HIV-1 infection may be associated with an increased risk of bleeding. This prospective, randomized, open-label trial in healthy volunteers compared the effects of tipranavir/ritonavir (TPV/r), darunavir/ ritonavir (DRV/r), and ritonavir (RTV) alone on platelet aggregation after a single dose and at steady-state concentrations. Subjects were selected on the basis of normal platelet aggregation and arachidonic acid (AA)-induced platelet aggregation inhibition after administration of a single 325-mg dose of aspirin. All 3 PI therapies were administered twice daily for 10 days. In some but not all subjects, TPV/r inhibited AA-induced platelet aggregation and prolonged PFA-100® closure time with collagen-epinephrine cartridge, which was of lesser magnitude and consistency compared with aspirin, but greater when compared to DRV/r and RTV. At least 2 subjects in each treatment arm showed complete inhibition of AA-induced platelet aggregation on treatment, and the magnitude of change in all platelet-function tests did not correlate with PI plasma concentrations. Effects of TPV/r on platelet aggregation were reversed 24 hours after the last TPV/r dose. None of the PI treatments tested were associated with increases in bleeding time, decreases in plasma coagulation factors, or increase in fibrinolysis. There was large inter-patient variability in antiplatelet effect for all PI treatments, ranging from no effect to complete inhibition of AA-induced platelet aggregation.


Assuntos
Fibrinólise/efeitos dos fármacos , Inibidores da Protease de HIV/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Piridinas/farmacologia , Pironas/farmacologia , Ritonavir/farmacologia , Sulfonamidas/farmacologia , Adulto , Coagulação Sanguínea/efeitos dos fármacos , Fatores de Coagulação Sanguínea/efeitos dos fármacos , Darunavir , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
11.
J Neuroimmunol ; 173(1-2): 23-34, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16386804

RESUMO

The role of astrocytes in the pathogenesis of multiple sclerosis (MS) is not well understood. Astrocytes may modulate the activity of pathogenic T cells by presenting myelin antigens in combination with pro- or anti-inflammatory signals. Astrocytes have been shown to present myelin basic protein (MBP) and proteolipid protein (PLP) to T cells, but it has remained unresolved whether astrocytes present myelin oligodendrocyte glycoprotein (MOG), which has been implicated as an important autoantigen in MS. Here, we asked whether astrocytes presented MOG to T cells. To closer model presentation of human MOG by astrocytes in MS patients, we generated astrocytes from transgenic mice expressing the MS-associated MHC class II alleles HLA-DR2 (DRB1*1501) and HLA-DR4 (DRB1*0401). The results show that IFN-gamma-activated HLA-DR2 and HLA-DR4 expressing astrocytes efficiently presented immunodominant and subdominant MOG peptides to T cells. The hierarchy of the presented MOG epitopes was comparable to that of professional APCs, including dendritic cells and microglia. Importantly, astrocytes were poor at processing and presenting native MOG protein. Furthermore, astrocytes induced a mixed Th1/Th2 cytokine response in MOG-specific T cells, whereas dendritic cells induced a predominantly Th1 cell response. Collectively, the results suggest that astrocytes may modulate anti-MOG T cell responses in the CNS.


Assuntos
Apresentação de Antígeno/imunologia , Astrócitos/imunologia , Encefalomielite Autoimune Experimental/imunologia , Glicoproteína Associada a Mielina/imunologia , Fragmentos de Peptídeos/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Modelos Animais de Doenças , Epitopos de Linfócito T/imunologia , Citometria de Fluxo , Antígeno HLA-DR2/genética , Antígeno HLA-DR4/genética , Humanos , Ativação Linfocitária/imunologia , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência , Proteínas da Mielina , Glicoproteína Mielina-Oligodendrócito , Linfócitos T/imunologia
12.
J Immunol ; 170(3): 1274-82, 2003 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-12538686

RESUMO

Macrophage migration inhibitory factor (MIF) is a cytokine that plays a critical role in the regulation of macrophage effector functions and T cell activation. However, its role in the pathogenesis of T cell-mediated autoimmune diseases, such as experimental autoimmune encephalomyelitis (EAE), has remained unresolved. In this study, we report that anti-MIF Ab treatment of SJL mice with acute EAE improved the disease severity and accelerated the recovery. Furthermore, the anti-MIF treatment impaired the homing of neuroantigen-reactive pathogenic T cells to the CNS in a VCAM-1-dependent fashion. Interestingly, MIF blockade also decreased the clonal size of the neuroantigen-specific Th1 cells and increased their activation threshold. Taken together, the results demonstrate an important role for MIF in the pathogenesis of EAE/multiple sclerosis and suggest that MIF blockade may be a promising new strategy for the treatment of multiple sclerosis.


Assuntos
Movimento Celular/imunologia , Sistema Nervoso Central/imunologia , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/prevenção & controle , Fatores Inibidores da Migração de Macrófagos/antagonistas & inibidores , Subpopulações de Linfócitos T/imunologia , Doença Aguda , Animais , Células Cultivadas , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Relação Dose-Resposta Imunológica , Regulação para Baixo/imunologia , Encefalomielite Autoimune Experimental/patologia , Epitopos de Linfócito T/imunologia , Feminino , Soros Imunes/administração & dosagem , Injeções Intraperitoneais , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Fatores Inibidores da Migração de Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Proteína Proteolipídica de Mielina/imunologia , Fragmentos de Peptídeos/imunologia , Índice de Gravidade de Doença , Subpopulações de Linfócitos T/patologia , Molécula 1 de Adesão de Célula Vascular/biossíntese
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