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1.
Mult Scler Relat Disord ; 76: 104747, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37267685

RESUMO

Multiple sclerosis (MS) is a chronic neuroinflammatory and neurodegenerative disease of the central nervous system (CNS). The etiology of MS is not well understood, but it's likely one of the genetic and environmental factors. Approximately 85% of patients have relapsing-remitting MS (RRMS), while 10-15% have primary progressive MS (PPMS). Epstein-Barr virus (EBV) and Human herpesvirus 6 (HHV-6), members of the human Herpesviridae family, are strong candidates for representing the macroenvironmental factors associated with MS) pathogenesis. Antigenic mimicry of EBV involving B-cells has been implicate in MS risk factors and concomitance of EBV and HHV-6 latent infection has been associated to inflammatory MS cascade. To verify the possible role of EBV and HHV-6 as triggering or aggravating factors in RRMS and PPMS, we compare their frequency in blood samples collected from 166 MS patients. The presence of herpes DNA was searched by real-time PCR (qPCR). The frequency of EBV and HHV-6 in MS patients were 1.8% (3/166) and 8.9% (14/166), respectively. Among the positive patients, 100% (3/3) EBV and 85.8% (12/14) HHV-6 are RRMS and 14.4% (2/14) HHV-6 are PPMS. Detection of EBV was 1.2% (2/166) and HHV-6 was 0.6% (1/166) in blood donors. About clinical phenotype of these patients, incomplete multifocal myelitis, and optic neuritis were the main CNS manifestations. These are the first data about concomitant infection of these viruses in MS patients from Brazil. Up to date, our findings confirm a higher prevalence in female with MS and a high frequency of EBV and HHV-6 in RRMS patients.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 6 , Esclerose Múltipla , Doenças Neurodegenerativas , Humanos , Feminino , Herpesvirus Humano 4/genética , Herpesvirus Humano 6/genética , DNA Viral , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/epidemiologia , Brasil/epidemiologia
2.
Viruses ; 15(1)2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36680226

RESUMO

Although chronic hepatitis C has been effectively treated with direct-acting antivirals (DAAs), the use of conventional therapy with peg-interferon (Peg-IFN) or (predominantly) ribavirin (RBV), remains widespread. R70Q/H and L/C91M amino acid substitutions in the hepatitis C virus (HCV) core protein may modulate responses to IFN and/or RBV, and are associated with cirrhosis, hepatocellular carcinoma (HCC), insulin resistance, and liver steatosis. We evaluated the R70Q/H and L/C91M substitutions, clinical and epidemiological profiles, and risk factors of Brazilian patients chronically infected with HCV subgenotypes 1a and 1b (HCV-GT1a and HCV-GT1b) unresponsive to IFN and/or RBV therapy. Sequencing and pyrosequencing analyses and sociodemographic and clinical predictive variables were used to assess the relationship between R70Q/H and L/C91M substitutions. Leukocyte counts, ALT levels, and ALT/AST ratios were significantly reduced in treated individuals, but more of these patients had advanced fibrosis and cirrhosis. L91M was more prevalent (19.7%), occurring only in HCV-GT1b, followed by R70Q/P (11.5%) and R70P (1.4%). R70Q/P exhibited higher mean AST, ALT, and GGT values, whereas L91M showed higher mean GGT values. Pyrosequencing of the L91M position revealed mutant subpopulations in 43.75% of samples.


Assuntos
Carcinoma Hepatocelular , Hepatite C Crônica , Hepatite C , Neoplasias Hepáticas , Humanos , Antivirais , Brasil/epidemiologia , Carcinoma Hepatocelular/tratamento farmacológico , Quimioterapia Combinada , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico
3.
J Appl Microbiol ; 132(3): 1616-1635, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34724308

RESUMO

Occult hepatitis B infection (OBI) is characterized by the detection of hepatitis B virus (HBV) DNA in serum or liver but negativity for hepatitis B surface antigen. OBI, which is thought to be maintained by host, immunological, viral and/or epigenetic factors, is one of the most challenging clinical features in the study of viral hepatitis. Currently, there is no validated detection test for OBI. It is believed that OBI is widely distributed throughout the world, with a higher prevalence in populations at high-risk HBV, but the detailed worldwide prevalence patterns are unknown. We conducted a survey of recently published studies on OBI rates across all continents. High prevalence rates of OBI are observed in some specific groups, including patients with hepatitis C virus, human immunodeficiency virus co-infection or hepatocellular carcinoma. In 2016, the World Health Organization adopted strategies to eliminate viral hepatitis by 2030, but the difficulties in detecting and treating OBI currently challenge this goal. Subjects with OBI can transmit HBV, and episodes of reactivation can occur. Further studies to understanding the mechanisms that drive the development of OBI are needed and can contribute to efforts at eliminating viral hepatitis.


Assuntos
Hepatite B Crônica , Hepatite B , Neoplasias Hepáticas , DNA Viral/genética , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Vírus da Hepatite B/genética , Hepatite B Crônica/epidemiologia , Humanos , Prevalência
4.
Microbiol Immunol ; 66(1): 31-39, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34647645

RESUMO

Hepatitis B virus (HBV) is one of the leading causes of acute and chronic hepatitis and represents a serious public health threat. Cytokines are important chemical mediators that regulate the differentiation, proliferation, and function of immune cells, with accumulating evidence indicating that the inadequate immune responses are responsible for the elimination or persistence of HBV. This study aimed to determine the cytokine profiles (IFN-γ, TNF-α, IL-2, IL-4, IL-6, IL-10, and IL-17A) during HBV infection and investigate their association with genotypes. A total of 66 plasma samples, 19 from patients with acute and 47 with chronic hepatitis B infection, were subjected to biochemical tests, nested-PCR, and real-time PCR, with cytokines evaluated using a commercial BD Cytometric Bead Array Human Th1/Th2/Th17 Cytokine Kit. Healthy controls (10 individuals) were selected from blood donors with no history of liver diseases. No correlation was found between genotypes, viral load, and cytokines analyzed. All cytokines showed higher levels of production among infected individuals when compared with the control group. A positive correlation classified as moderate to strong was found between cytokines IFN-γ, TNF, IL-10, IL-6, IL-4, and IL-2 through the Spearman correlation coefficient. TNF (P = 0.009), IL-10 (P < 0.001), and IL-6 (P < 0.001) levels were higher in acute individuals compared with chronic and control groups. Theses cytokines could be involved in the elimination of virus and protection against chronicity.


Assuntos
Hepatite B Crônica , Hepatite B , Citocinas , Vírus da Hepatite B/genética , Humanos , Interferon gama
5.
Viruses ; 13(5)2021 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-34063186

RESUMO

Immunotherapy has been shown to be highly effective in some types of cancer caused by viruses. Gene therapy involves insertion or modification of a therapeutic gene, to correct for inappropriate gene products that cause/may cause diseases. Both these types of therapy have been used as alternative ways to avoid cancers caused by oncoviruses. In this review, we summarize recent studies on immunotherapy and gene therapy including the topics of oncolytic immunotherapy, immune checkpoint inhibitors, gene replacement, antisense oligonucleotides, RNA interference, clustered regularly interspaced short palindromic repeats Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based gene editing, transcription activator-like effector nucleases (TALENs) and custom treatment for Epstein-Barr virus, human T-lymphotropic virus 1, hepatitis B virus, human papillomavirus, hepatitis C virus, herpesvirus associated with Kaposi's sarcoma, Merkel cell polyomavirus, and cytomegalovirus.


Assuntos
Terapia Genética , Imunoterapia , Infecções por Retroviridae/terapia , Retroviridae/fisiologia , Animais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Edição de Genes , Humanos , Retroviridae/genética , Infecções por Retroviridae/genética , Infecções por Retroviridae/imunologia , Infecções por Retroviridae/virologia
6.
Virol J ; 18(1): 15, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33435966

RESUMO

BACKGROUND: The hepatitis B virus (HBV) is one of the leading causes of acute, chronic and occult hepatitis (OBI) representing a serious public health threat. Cytokines are known to be important chemical mediators that regulate the differentiation, proliferation and function of immune cells. Accumulating evidence indicate that the inadequate immune responses are responsible for HBV persistency. The aim of this study were to investigate the cytokines IFN-γ, TNF-α, IL-2, IL-4, IL-6, IL-10 and IL-17A in patients with OBI and verify if there is an association between the levels of these cytokines with the determination of clinical courses during HBV occult infection. METHODS: 114 patients with chronic hepatitis C were investigated through serological and molecular tests, the OBI coinfected patients were subjected to the test for cytokines using the commercial human CBA kit. As controls, ten healthy donors with no history of liver disease and 10 chronic HBV monoinfected patients of similar age to OBI patients were selected. RESULTS: Among 114 HCV patients investigated, 11 individuals had occult hepatitis B. The levels of cytokines were heterogeneous between the groups, most of the cytokines showed higher levels of production detection among OBI/HCV individuals when compared to control group and HBV monoinfected pacients. We found a high level of IL-17A in the HBV monoinfected group, high levels of TNF-α, IL-10, IL-6, IL-4 and IL-2 in OBI/HCV patients. CONCLUSION: These cytokines could be involved in the persistence of HBV DNA in hepatocytes triggers a constant immune response, inducing continuous liver inflammation, which can accelerate liver damage and favor the development of liver cirrhosis in other chronic liver diseases.


Assuntos
Coinfecção/imunologia , Coinfecção/virologia , Citocinas/sangue , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatite C Crônica/virologia , Idoso , Estudos Transversais , Citocinas/classificação , Citocinas/imunologia , DNA Viral/análise , DNA Viral/genética , Feminino , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite C Crônica/complicações , Hepatócitos/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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