Development and evaluation of a pre-analytical device for liquid biopsy

Sammanfattning: In this project, a novel method to discover and monitor cancer was studied. Tumoureducated platelets (TEPs) have shown the ability to take up tumour-derived secretedmembrane vesicles, which contain tumour RNA. Therefore they are of great interestfor detecting cancer and could potentially work as biomarkers. One problem withusing blood platelets as a source of biomarkers is that clinical implementation isprevented by pre-analytical procedures that are difficult to perform in clinicallaboratories. In this study, human blood samples have been used to investigatewhether density gradient centrifugation followed by microfiltration could result inpure platelet (PLT) fractions. The idea is to enable parallel extraction of multiplesources of biomarkers from a single liquid biopsy, namely peripheral bloodmononuclear cells (PBMCs), PLTs and plasma. The procedure was done by firstresuspending the buffy coat in plasma after the centrifugation, where some cells werefixed and then filtered through a combination of membranes. From that, PLT fractionsfree from any nucleated cell could be obtained both for fixed and unfixed cells. Thenext step will be to detect tumour-specific transcripts in PLTs by investigatingwhether the purity of the extracted mRNA is sufficient for these kinds of procedures.This method holds great promise for creating a procedure to isolate, extract andanalyse several biomolecule fractions from a single liquid biopsy. Further studies couldinclude other biomarkers of interest such as circulating tumour DNA (ctDNA),extracellular vesicles (EVs) and plasma proteins.