COVID-19 is an acute infectious disease of the respiratory system caused by infection with the SARS-CoV-2 virus (Severe Acute Respiratory Syndrome Coronavirus 2). Transmission of SARS-CoV-2 infections occurs through droplets and contaminated objects. A rapid and well-coordinated immune system response is the first line of defense in a viral infection. However, a disturbed and over-activated immune response may be counterproductive, causing damage to the body. Severely ill patients hospitalised with COVID-19 exhibit increased levels of many cytokines, including Interleukin (IL)-1β, IL-2, IL-6, IL-7, IL-8, IL-10, IL-17, granulocyte colony stimulating factor (G-CSF), monocyte chemoattractant protein 1 (MCP-1) and tumor necrosis factor (TNF). Increasing evidence suggests that Th17 cells play an important role in the pathogenesis of COVID-19, not only by activating cytokine cascade but also by inducing Th2 responses, inhibiting Th1 differentiation and suppressing Treg cells. This review focuses on a Th17 pathway in the course of the immune response in COVID-19, and explores plausible targets for therapeutic intervention.

Role of cannabinoids in chronic liver diseases

Hepatitis C virus (HCV) infection affects 180 million people worldwide with the predominant prevalence being infection with genotype 1, followed by genotypes 2 and 3. Standard anti-HCV therapy currently aims to enhance natural immune responses to the virus, whereas new therapeutic concepts directly target HCV RNA and viral enzymes or influence host-virus interactions. Novel treatment options now in development are focused on inhibitors of HCV-specific enzymes, NS3 protease and NS5B polymerase. These agents acting in concert represent the concept of specifically targeted antiviral therapy for HCV (STAT-C). STAT-C is an attractive strategy in which the main goal is to increase the effectiveness of antiviral responses across all genotypes, with shorter treatment duration and better tolerability. However, the emergence of resistant mutations that limit the use of these compounds in monotherapy complicates the regimens. Thus, a predictable scenario for HCV treatment in the future will be combinations of drugs with distinct mechanisms of action. For now, it seems that interferon will remain a fundamental component of any new anti-HCV therapeutic regimens in the near future; therefore, there is pressure to develop forms of interferon that are more effective, less toxic, and more convenient than pegylated interferon.

Importance of the field: Hepatitis C virus (HCV) infection affects 180 million people worldwide. Standard anti-HCV therapy combines effect of pegylated IFN-alpha on immune response and antiviral activity of ribavirin. Sustained virological response rate achieved with this standard of care medication is around 50% for HCV genotype 1, the most prevalent worldwide genotype. So there is an obvious need to enhance efficacy of treatment.Areas covered in this review: We describe novel treatment options studied within the recent few years, which are focused on inhibitors of HCV-specific enzymes such as NS3/4 protease and NS5B polymerase or influence host-virus interactions.What the reader will gain: According to the most recent data, triple therapies consisted of pegylated interferons, ribavirin and protease inhibitors demonstrate significant improvement of treatment efficacy in comparison to current standard of care medication. Moreover, new forms of interferons and ribavirin, more effective, less toxic, and mor...

About 2.35% of the world population can be infected with hepatitis C virus (HCV) responsible for chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. Currently available interferon-based medication is successful in up to 75% of the patients infected with HCV genotypes 1, 2 or 3 and lower efficacy in other genotypes. Unfortunately sustained virologic response (SVR) rate in genotype 1 infected non-responders to previous therapy with advanced hepatic fibrosis even after retreatment with the first generation direct acting antivirals (DAA) is about 40% only. The second generation DAA, which have recently been submitted for registration (Sofosbuvir and Simeprevir) still need combination with PegIFNα and RBV in patients infected with HCV genotype 1. There is a need for more effective antiviral therapy for difficult to treat patients who are interferon intolerant, developed liver cirrhosis or non-responders to previous therapies. Therefore, IFN-free regimens are step for future therapies consisting of combinations of novel investigational DAA and host targeting agents. The introduction of novel DAA with a good safety profile and high barrier to resistance can lead to SVR rates exceeding 90% in treatment naïve patients and non-responders to previous therapy infected with different genotypes.