Metcalf, B. | bioRxiv Science

bioRxiv2024

A Portable and Scalable Genomic Analysis Pipeline for Streptococcus pneumoniae Surveillance: GPS Pipeline

Ever increasing global sequencing capacity provides an unprecedented opportunity in utilising genomic information captured from whole-genome sequencing to enhance pathogen surveillance. However, there is a growing need for developing user-friendly tools to effectively analyse the increasing volume of data. To meet this need, we have developed a genomic analysis pipeline, GPS Pipeline, which is portable and scalable to analyse genomes of Streptococcus pneumoniae, a major bacterial pathogen that is estimated to cause 317,000 child deaths worldwide every year. The GPS Pipeline is based on Nextflow and containerisation technology, and designed to enable researchers generating public health relevant output, including in silico serotypes, pneumococcal lineages (i.e. GPSCs), multilocus sequence types, and antimicrobial susceptibilities against 20 commonly used antibiotics,with minimal software setup requirements and bioinformatic expertise, in order to analyse genomic data at scale with ease. The GPS Pipeline provides a streamlined workflow that improves responsiveness in genomic surveillance on pneumococci. Data SummaryThe GPS Pipeline is available on GitHub at github.com/GlobalPneumoSeq/gps-pipeline. Published data from the GPS Database is available on Monocle Data Viewer at data.monocle.sanger.ac.uk and associated sequence read files are searchable and downloadable in the European Nucleotide Archive at ebi.ac.uk/ena via their ERR accession numbers. Impact StatementThe GPS Pipeline advances global genomic surveillance of Streptococcus pneumoniae by providing a scalable, portable, and user-friendly tool for analysing whole-genome sequencing data. Leveraging Nextflow and containerisation technology, it minimises bioinformatics expertise requirements and infrastructure needs, making it particularly valuable in low- and middle-income countries where pneumococcal disease burden is high. This pipeline ensures reproducibility and stability across platforms, facilitating rapid and accurate pneumococci genomic analysis. By streamlining data processing, the GPS Pipeline enhances pathogen surveillance, generates evidence to support vaccine strategy development, and empowers researchers worldwide, ultimately contributing to improved public health outcomes.

genomics↗

bioRxiv2019

The a-isoform of VEGFA165 is a Significantly Stronger Activator of Human Retinal Endothelial Cells compared to the b-isoform

PurposeThere are reports that a b-isoform of Vascular Endothelial Growth Factor-A-165 (VEGFA165b) is predominant in normal human vitreous, switching to the a-isoform (VEGFA165a) in the vitreous of some diseased eyes. While these isoforms appear to have a different ability to activate the VEGF-Receptor-2 (VEGFR2) in various endothelial cells, the nature of their ability to activate intracellular signalling pathways is not fully characterized, especially in retinal endothelial cells. We determined their activation potential for two key intracellular signalling pathways (MAPK, AKT) over complete dose-response curves and compared potential effects on the expression of several VEGFA165 target genes in primary human retinal microvascular endothelial cells (HRMECs). MethodsTo determine full dose-response curves for the activation of MAPK (ERK1/2), AKT and VEGFR2, direct in-cell western assays were developed using primary Human Retinal Microvascular Endothelial Cells (HRMECs). Potential differences in dose-response effects on gene expression markers related to endothelial cell / leukocyte adhesion (ICAM1, VCAM1 and SELE) and tight-junctions (CLDN5 and OCLN) were tested by quantitative-PCR. ResultsActivation dose-response analysis revealed much stronger activation of MAPK, AKT and VEGFR2 by the a-isoform at lower doses. MAPK activation in primary HRMECs displayed a sigmoidal dose-response to a range of VEGFA165a concentrations spanning 10-250 pM, which shifted higher into the 100-5,000 pM range with VEGFA165b. Similar maximum activation of MAPK was achieved by both isoforms at high concentration. Maximum activation of AKT by VEGFA165b was only half of the maximum activation from VEGFA165a. At a lower intermediate dose, where VEGFA165a activated intracellular signalling stronger than VEGFA165b, the changes to VEGFA target gene expression was generally greater with VEGFA165a. ConclusionsIn primary HRMECs, VEGFA165a could maximally activate MAPK and AKT at lower concentrations where VEGFA165b had relatively little effect. The timing for maximal activation of MAPK was similar for both isoforms, which is different than reprorted for non-retinal endothelial cells. While VEGFA165a and VEGFA165b are limited to the sequence of their six C-terminal six amino acids, this results in a large difference in their ablility to activate at least two key intracellular signalling pathways and potentially VEGF target gene expression in primary human retinal endothelial cells.

cell biology↗