[10][11] suPAR is a biomarker reflecting the level of activity of the immune system in response to an inflammatory stimulus.
A suPAR level below 4 ng/mL indicates a good prognosis in acute medical patients and supports discharge.
In COVID-19, an early elevation of suPAR, e.g. in patients that present with symptoms of SARS-CoV-2 infection, is associated with an increased risk of severe COVID-19 development, which may lead to respiratory failure, acute kidney injury, and death.
[21][22][23] In the kidneys, suPAR plays a role in regulating the permeability of the glomerular filtration barrier.
Comparing cDNA sequences, D1 differs from D2 and D3 in its primary and tertiary structure, causing its distinct ligand binding properties.
[1][27] uPAR has cleavage sites for several proteases in the linker region (chymotrypsin, elastase, matrix metalloproteases, cathepsin G, plasmin, urokinase plasminogen activator (uPA, or urokinase), and in the GPI anchor (phospholipase C and D, cathepsin G, plasmin).
[1] The molecular weight of suPAR varies between 24–66 kDa due to variations in posttranslational glycosylations.
[1] Additional isoforms generated by alternative splicing have been described on the RNA level, but whether these are transcribed and their possible roles remain unclear.
suPARnostic® is a CE-IVD certified antibody-based product range applied for quantitative measurements of suPAR in the clinical setting.