Matrix Metalloproteinases in Cytotoxic Lymphocytes Impact on Tumour Infiltration and Immunomodulation

To efficiently combat solid tumours, endogenously or adoptively transferred cytotoxic T cells and natural killer (NK) cells, need to leave the vasculature, traverse the interstitium and ultimately infiltrate the tumour mass. During this locomotion and migration in the three dimensional environment many obstacles need to be overcome, one of which is the possible impediment of the extracellular matrix. The first and obvious one is the sub-endothelial basement membrane but the infiltrating cells will also meet other, both loose and tight, matrix structures that need to be overridden. Matrix metalloproteinases (MMPs) are believed to be one of the most important endoprotease families, with more than 25 members, which together have function on all known matrix components. This review summarizes what is known on synthesis, expression patterns and regulation of MMPs in cytotoxic lymphocytes and their possible role in the process of tumour infiltration. We also discuss different functions of MMPs as well as the possible use of other lymphocyte proteases for matrix degradation

Treatment and Monitoring of Children with Chronic Hepatitis C in the Pre‐DAA Era: a European Survey of 38 Paediatric Specialists

The burden of paediatric Hepatitis C virus (HCV) infection across Europe is unknown, as are current policies regarding monitoring and treatment. This collaborative study aimed to collect aggregate data to characterise the population of ≤18-year-olds with HCV infection in specialist follow up in a 12-month period (2016) across the PENTAHep European consortium, and investigate current policies around monitoring and treatment. A cross-sectional, web-based survey was distributed in April 2017 to 50 paediatricians in 19 European countries, covering patients' profile, and monitoring and treatment practices. Responses were received from 38/50 clinicians collectively caring for 663 children with chronic HCV infection of whom three-quarters were aged ≥6 years and 90% vertically infected. HCV genotype 1 was the most common (n 380; 57.3%), followed by genotype 3, 4 and 2. Seventeen children (3%) with chronic HCV infection were diagnosed with cirrhosis, and six were reported to have received liver transplantation for HCV-related liver disease. The majority (n 425; 64.1%) of the European children with HCV infection remained treatment-naive in 2016. Age affected clinicians' attitudes towards treatment; 94% reported being willing to use direct-acting antivirals, if available, in adolescents (aged ≥11 years), 78% in children aged 6-10 and 42% in those 3-5 years of age (Pearson correlation coefficient -0.98; P 0.0001). This survey provides the largest characterisation of the population of children in clinical follow-up for chronic HCV infection in Europe, alongside important contextual information on their management and treatment. Discussion is needed around strategies and criteria for use of direct-acting antivirals in these children