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1.
Front Med (Lausanne) ; 9: 1019230, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36405584

RESUMO

Chronic viral infections represent a leading cause of global morbidity and mortality. Chronic HBV, HCV, and HIV infections result in cytokine perturbations that may hold key implications in understanding the complex disease mechanisms driving virus persistence and/or resolution. Here, we determined the levels of various plasma cytokines using a commercial Bio-Plex Luminex cytokine array in chronic HBV (n = 30), HCV (n = 15), and HIV (n = 40) infections and correlated with corresponding plasma viral loads (PVLs) and liver parameters. We observed differential perturbations in cytokine profiles among the study groups. The cytokines levels positively correlated with PVL and liver transaminases. The monocyte-derived cytokines viz., MIP-1ß, IL-8, and TNF-α, and Th2 cytokines like IL-4, IL-5, and IL-13 showed a better correlation with liver enzymes as compared to their corresponding PVLs. Our investigation also identified two cytokines viz., IL-5 and IL-7 that inversely correlated with HBV DNA and HIV PVLs, respectively. Regression analysis adjusted for age showed that every increase of IL-5 by one unit was associated with a reduction in HBV PVL by log10 0.4, whereas, every elevation by a unit of IL-7 was associated with decreased HIV PVL by log10 2.5. We also found that IL-7 levels correlated positively with absolute CD4+ T cell counts in HIV-infected patients. We concluded that plasma IL-5 and IL-7 may likely have a key role on viral control in HBV and HIV infections, respectively. A noteworthy increase in cytokines appears to bear protective and pathological significance, and indeed is reflective of the host's versatile immune armory against viral persistence.

2.
Front Immunol ; 9: 472, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29616020

RESUMO

Mucosal-associated invariant T (MAIT) cells, defined as CD161++TCR iVα7.2+ T cells, play an important role in the innate defense against bacterial infections, and their functionality is impaired in chronic viral infections. Here, we investigated the frequency and functional role of MAIT cells in chronic hepatitis B virus (HBV) infection. The peripheral CD3+CD161++TCR iVα7.2+ MAIT cells in chronic HBV-infected patients and healthy controls were phenotypically characterized based on CD57, PD-1, TIM-3, and CTLA-4, as well as HLA-DR and CD38 expression. The frequency of MAIT cells was significantly decreased among chronic HBV-infected individuals as compared to controls. Expression of CD57, PD-1, CTLA-4, as well as HLA-DR and CD38 on MAIT cells was significantly elevated in chronic HBV-infected individuals relative to controls. The percentage of T cell receptor (TCR) iVα7.2+ CD161+ MAIT cells did not correlate with HBV viral load but inversely with HLA-DR on CD4+ T cells and MAIT cells and with CD57 on CD8+ T cells suggesting that decrease of MAIT cells may not be attributed to direct infection by HBV but driven by HBV-induced chronic immune activation. The percentage and expression levels of PD-1 as well as CTLA-4 on MAIT cells inversely correlated with plasma HBV-DNA levels, which may suggest either a role for MAIT cells in the control of HBV infection or the effect of HBV replication in the liver on MAIT cell phenotype. We report that decrease of TCR iVα7.2+ MAIT cells in the peripheral blood and their functions were seemingly impaired in chronic HBV-infected patients likely because of the increased expression of PD-1.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Regulação da Expressão Gênica/imunologia , Hepatite B Crônica/imunologia , Subfamília B de Receptores Semelhantes a Lectina de Células NK/imunologia , Receptor de Morte Celular Programada 1/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Adulto , Linfócitos T CD8-Positivos/patologia , DNA Viral/imunologia , Feminino , Hepatite B Crônica/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa/imunologia , Mucosa/patologia
3.
Innate Immun ; 23(5): 459-467, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28606013

RESUMO

Hepatitis B virus (HBV) infection is a major cause of chronic liver disease that may progress to liver cirrhosis and hepatocellular carcinoma. Host immune responses represent the key determinants of HBV clearance or persistence. Here, we investigated the role of the early activation marker, CD69 and effector cytokines, granzyme B (GrB) and IFN-γ in the exhaustion of innate-like TCR Vα7.2+CD4+T cells, in 15 individuals with chronic HBV (CHB) infection where six were HBV DNA+ and nine were HBV DNA-. The percentage of cytokine-producing T cells and MAIT cells were significantly perturbed in HBV patients relative to healthy controls (HCs). The intracellular expression of GrB and IFN-γ was significantly reduced in MAIT cells derived from HBV-infected patients as compared to HCs, and the levels correlated with the percentage and levels [mean fluorescence intensity (MFI)] of CD69 expression. The total expression of CD69 (iMFI) was lower in CHB patients as compared to HCs. The frequency of CD69+ cells correlated with the levels of cytokine expression (MFI), particularly in CHB patients as compared to HCs. In summary, the polyfunctionality of peripheral T cells was significantly reduced among CHB patients, especially in the TCR Vα7.2+CD4+T cells, and the levels of cytokine expression correlated with functional cytokine levels.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos T CD4-Positivos/imunologia , Carcinoma Hepatocelular/imunologia , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/imunologia , Lectinas Tipo C/metabolismo , Neoplasias Hepáticas/imunologia , Células T Invariantes Associadas à Mucosa/imunologia , Adulto , Células Cultivadas , Citotoxicidade Imunológica , Feminino , Granzimas/metabolismo , Humanos , Imunidade Inata , Interferon gama/metabolismo , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Carga Viral
4.
Gastroenterology ; 123(6): 1831-8, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12454840

RESUMO

BACKGROUND & AIMS: Entecavir is a novel and selective nucleoside analogue with potent activity against hepatitis B virus (HBV). METHODS: In a 24-week, double-blind, randomized, multicenter, phase II clinical trial, the safety and efficacy of entecavir (0.01 mg/day, 0.1 mg/day, or 0.5 mg/day orally) were compared with lamivudine (100 mg/day orally). Patients (n = 169) chronically infected with HBV (hepatitis B e antigen [HBeAg]-positive and -negative) were evaluated for efficacy. RESULTS: Compared with lamivudine, entecavir reduced HBV DNA by an additional 0.97 log(10) at the 0.1-mg/day dose and an additional 1.28 log(10) at the 0.5-mg/day dose (P < 0.0001). A clear dose-response relationship was observed for entecavir with the higher doses showing significantly greater viral suppression. In patients treated with entecavir 0.5 mg/day, 83.7% had an HBV-DNA level below the lower limit of detection of the Quantiplex branched DNA (bDNA) assay (Bayer-Versant Diagnostics, formerly Chiron Diagnostics, Emeryville, CA), compared with 57.5% treated with 100 mg/day lamivudine (P = 0.008). In both treatment arms, very few patients achieved HBeAg loss and/or seroconversion by week 22. More patients treated with the 0.1-mg/day and 0.5-mg/day doses of entecavir had normalization of alanine transaminase (ALT) levels at week 22 compared with lamivudine (P = not significant). Entecavir was well tolerated; most adverse events were mild to moderate, transient, and comparable in all study arms. CONCLUSIONS: This study showed that entecavir has potent antiviral activity against HBV at 0.1-mg/day and 0.5-mg/day doses, both of which were superior to lamivudine in chronically infected HBV patients.


Assuntos
DNA Viral/metabolismo , Guanina/análogos & derivados , Guanina/uso terapêutico , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Lamivudina/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Adolescente , Adulto , Alanina Transaminase/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Guanina/administração & dosagem , Guanina/efeitos adversos , Antígenos E da Hepatite B/análise , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/genética , Hepatite B Crônica/patologia , Humanos , Lamivudina/administração & dosagem , Lamivudina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Inibidores da Transcriptase Reversa/administração & dosagem , Inibidores da Transcriptase Reversa/efeitos adversos , Resultado do Tratamento , Carga Viral
5.
J Gastroenterol Hepatol ; 17(3): 281-4, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11982698

RESUMO

BACKGROUND: The majority of colorectal cancers are still diagnosed in patients who present with symptoms especially in countries where colorectal screening programs are not practised. The aim of our study was to determine the predictive factors for colorectal cancer in patients referred for colonoscopy. METHODS: A prospective study of 485 consecutive patients who underwent colonoscopy during a 22-month period was performed. All patients answered a detailed questionnaire. Indications for colonoscopy and the findings were recorded. RESULTS: The mean age of the study population was 55.7 +/- 14.7 years. There were 221 (45.6%) males and 264 (54.4%) females. Sixty-five (13.4%) were Malays, 298 (61.4%) were Chinese and 112 (23.1%) were Indians. Multiple backward stepwise regression analysis revealed that independent predictors for colorectal cancer (odds ratio [95% CI]) were the presence of rectal bleeding (4.3 [4.0-8.0]) and iron deficiency anemia (4.0 [3.6-10.2]). In those aged 50 and over, male gender (4.5 [2.2-9.3]) and abdominal pain (3.1 [1.4-6.7]) were also significant positive predictors of cancer. CONCLUSIONS: With the ever-increasing demand for gastrointestinal endoscopy, the appropriate utilization of colonoscopy is essential to afford prompt patient evaluation. Our study supports the need to prioritize the use of colonoscopy in patients with rectal bleeding and iron deficiency anemia. In the older patient where the background prevalence of colorectal cancer is higher, referral for colonoscopy is also justified.


Assuntos
Neoplasias Colorretais/epidemiologia , Anemia Ferropriva/epidemiologia , Colonoscopia , Neoplasias Colorretais/diagnóstico , Estudos Transversais , Feminino , Hemorragia Gastrointestinal/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Estudos Prospectivos , Reto , Análise de Regressão , Fatores de Risco
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