Circulating extracellular DNA (ecDNA) is known to worsen the outcome of many diseases. ecDNA released from neutrophils during infection or inflammation is present in the form of neutrophil extracellular traps (NETs). It has been shown that higher ecDNA concentration occurs in a number of inflammatory diseases including inflammatory bowel disease (IBD). Enzymes such as peptidyl arginine deiminases (PADs) are crucial for NET formation. We sought to describe the dynamics of ecDNA concentrations and fragmentation, along with NETosis during a mouse model of chemically induced colitis. Plasma ecDNA concentration was highest on day seven of dextran sulfate sodium (DSS) intake and the increase was time-dependent. This increase correlated with the percentage of cells undergoing NETosis and other markers of disease activity. Relative proportion of nuclear ecDNA increased towards more severe colitis; however, absolute amount decreased. In colon explant medium, the highest concentration of ecDNA was on day three of DSS consumption. Early administration of PAD4 inhibitors did not alleviate disease activity, but lowered the ecDNA concentration. These results uncover the biological characteristics of ecDNA in IBD and support the role of ecDNA in intestinal inflammation. The therapeutic intervention aimed at NETs and/or nuclear ecDNA has yet to be fully investigated.
13 October 2022 in Comparative Immunology, Microbiology and Infectious Diseases
The porcine enteric virome comprises a wide range of eukaryotic and prokaryotic viruses in healthy and diarrheic pigs. As RNA viruses are considered to be important agents responsible for diarrhoea in pigs, this work was focused on the RNA virome. To identify viruses, a next generation sequencing technique and bioinformatics analysis was employed. A wide spectrum of viral genera with RNA genomes, such as Kobuvirus, Picobirnavirus, Teschovirus, Posavirus, Mamastovirus, Enterovirus and Rotavirus were identified in both diarrheic and healthy pigs. No clear differences in the virome composition were found between healthy and diarrheic pigs. The data visualisation using Non-Metric Multidimensional Scaling as well as by the Analysis of Similarities test suggested that the virome depended on the age of animals and differed in piglets when compared to weaned and fattening pigs.
Low-coverage massively parallel genome sequencing for non-invasive prenatal testing (NIPT) of common aneuploidies is one of the most rapidly adopted and relatively low-cost DNA tests. Since aggregation of reads from a large number of samples allows overcoming the problems of extremely low coverage of individual samples, we describe the possible re-use of the data generated during NIPT testing for genome scale population specific frequency determination of small DNA variants, requiring no additional costs except of those for the NIPT test itself. We applied our method to a data set comprising of 1,548 original NIPT test results and evaluated the findings on different levels, from in silico population frequency comparisons up to wet lab validation analyses using a gold-standard method. The revealed high reliability of variant calling and allelic frequency determinations suggest that these NIPT data could serve as valuable alternatives to large scale population studies even for smaller countries around the world.