Risultati per: Papilloma virus

Introduction
Kidney transplant recipients (KTRs) suffer from immunosuppression-related adverse events (iRAEs), such as infections and malignancy from chronic immunosuppression, but are also at risk of graft loss from rejection with underimmunosuppression. Biomarkers that predict both iRAEs and rejection while allowing individualisation of immunosuppression exposure are lacking. Although plasma viral DNA levels of torque teno virus (TTV), a widely prevalent, non-pathogenic virus, have been shown to predict both iRAE and rejection in newly transplanted KTRs within the first year after transplant, its role for prevalent KTRs on stable immunosuppression is less clear.
This study aims to determine the prognostic value of TTV levels for severe infections (defined as infections requiring hospitalisation) in prevalent KTRs on stable immunosuppression for at least 3 months and compare it against that of other commonly available biomarkers. The study also aims to explore the relationship between TTV levels and factors affecting the ‘net state of immunosuppression’ as well as other clinical outcomes.

Methods and analysis
This is a single-centre, prospective, observational cohort study of 172 KTRs on stable immunosuppression for more than 3 months. TTV levels will be measured using the TTV R-GENE kit upon recruitment when study subjects are admitted and when kidney allograft biopsies are performed. Subjects will be monitored for iRAEs and rejection for at least 12 months. The relationship between TTV load and clinical outcomes such as severe infections will be analysed and compared against that from other common biomarkers and previously published predictive scores.

Ethics and dissemination
The study was approved by the SingHealth Centralised Institutional Review Board (2023/2170). The results will be presented at conferences and submitted for publication in peer-reviewed journals.

Trial registration number
NCT05836636.

E’ un giovane di 25 anni. Condizioni cliniche in miglioramento

Objective
Exhausted T cells with limited effector function are enriched in chronic hepatitis B and C virus (HBV and HCV) infection. Metabolic regulation contributes to exhaustion, but it remains unclear how metabolism relates to different exhaustion states, is impacted by antiviral therapy, and if metabolic checkpoints regulate dysfunction.

Design
Metabolic state, exhaustion and transcriptome of virus-specific CD8+ T cells from chronic HBV-infected (n=31) and HCV-infected patients (n=52) were determined ex vivo and during direct-acting antiviral (DAA) therapy. Metabolic flux and metabolic checkpoints were tested in vitro. Intrahepatic virus-specific CD8+ T cells were analysed by scRNA-Seq in a HBV-replicating murine in vivo model of acute and chronic infection.

Results
HBV-specific (core18-27, polymerase455-463) and HCV-specific (NS31073-1081, NS31406-1415, NS5B2594-2602) CD8+ T cell responses exhibit heterogeneous metabolic profiles connected to their exhaustion states. The metabolic state was connected to the exhaustion profile rather than the aetiology of infection. Mitochondrial impairment despite intact glucose uptake was prominent in severely exhausted T cells linked to elevated liver inflammation in chronic HCV infection and in HBV polymerase455-463 -specific CD8+ T cell responses. In contrast, relative metabolic fitness was observed in HBeAg-negative HBV infection in HBV core18-27-specific responses. DAA therapy partially improved mitochondrial programmes in severely exhausted HCV-specific T cells and enriched metabolically fit precursors. We identified enolase as a metabolic checkpoint in exhausted T cells. Metabolic bypassing improved glycolysis and T cell effector function. Similarly, enolase deficiency was observed in intrahepatic HBV-specific CD8+ T cells in a murine model of chronic infection.

Conclusion
Metabolism of HBV-specific and HCV-specific T cells is strongly connected to their exhaustion severity. Our results highlight enolase as metabolic regulator of severely exhausted T cells. They connect differential bioenergetic fitness with distinct exhaustion subtypes and varying liver disease, with implications for therapeutic strategies.

Annals of Internal Medicine, Ahead of Print.

Annals of Internal Medicine, Ahead of Print.

Con i corvi, rappresentano indicatore di malattia in un’area

New England Journal of Medicine, Volume 389, Issue 9, Page 808-819, August 2023.

Palù: aiuterà nel controllo delle future emergenze pandemiche

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Per proteggere gli anziani e i bambini fino a sei mesi di età

Proteggere gli anziani e i bambini fino a sei mesi di età

The leading causes of death are drug-related and liver disease–related.

Circulation, Ahead of Print. BACKGROUND:Cardiac reprogramming is a technique to directly convert nonmyocytes into myocardial cells using genes or small molecules. This intervention provides functional benefit to the rodent heart when delivered at the time of myocardial infarction or activated transgenically up to 4 weeks after myocardial infarction. Yet, several hurdles have prevented the advancement of cardiac reprogramming for clinical use.METHODS:Through a combination of screening and rational design, we identified a cardiac reprogramming cocktail that can be encoded in a single adeno-associated virus. We also created a novel adeno-associated virus capsid that can transduce cardiac fibroblasts more efficiently than available parental serotypes by mutating posttranslationally modified capsid residues. Because a constitutive promoter was needed to drive high expression of these cell fate–altering reprogramming factors, we included binding sites to a cardiomyocyte-restricted microRNA within the 3’ untranslated region of the expression cassette that limits expression to nonmyocytes. After optimizing this expression cassette to reprogram human cardiac fibroblasts into induced cardiomyocyte-like cells in vitro, we also tested the ability of this capsid/cassette combination to confer functional benefit in acute mouse myocardial infarction and chronic rat myocardial infarction models.RESULTS:We demonstrated sustained, dose-dependent improvement in cardiac function when treating a rat model 2 weeks after myocardial infarction, showing that cardiac reprogramming, when delivered in a single, clinically relevant adeno-associated virus vector, can support functional improvement in the postremodeled heart. This benefit was not observed with GFP (green fluorescent protein) or a hepatocyte reprogramming cocktail and was achieved even in the presence of immunosuppression, supporting myocyte formation as the underlying mechanism.CONCLUSIONS:Collectively, these results advance the application of cardiac reprogramming gene therapy as a viable therapeutic approach to treat chronic heart failure resulting from ischemic injury.

New England Journal of Medicine, Volume 389, Issue 7, Page 676-676, August 2023.

Da ricercatori italiani e americani. Utile anche contro i tumori

Hepatitis B virus (HBV) causes chronic infection in at least 250 million people worldwide, resulting in approximately 850 000 deaths annually. Chronic carriers are at risk of developing severe liver disease including decompensated cirrhosis and hepatocellular carcinoma (HCC). HBV infection can be prevented with a highly effective prophylactic vaccine. Viraemia can be suppressed with nucleos/tide analogues targeting the HBV polymerase, but standard-of-care therapy rarely leads to a cure leaving patients requiring lifelong therapy to prevent relapse of viral replication. Furthermore, even on treatment patients remain at a residual risk of developing HCC. Development of treatments resulting in a functional cure has been hampered by our incomplete understanding of HBV persistence and the difficulty of targeting pharmacologically essential steps in the viral replicative cycle.1 HBV is a partially double-stranded DNA virus of the Hepadnaviridae family, which has a complex replication cycle and is intricately intertwined with the host cell DNA…