RT Journal Article SR Electronic T1 Both lipopolysaccharide and lipoteichoic acids potently induce anomalous fibrin amyloid formation: assessment with novel Amytracker™ stains JF bioRxiv FD Cold Spring Harbor Laboratory SP 143867 DO 10.1101/143867 A1 Etheresia Pretorius A1 Martin J Page A1 Lisa Hendricks A1 Nondumiso B Nkosi A1 Sven R Benson A1 Douglas B Kell YR 2017 UL http://biorxiv.org/content/early/2017/05/30/143867.abstract AB In recent work, we discovered that the presence of highly substoichiometric amounts (10-8 molar ratio) of lipopolysaccharide (LPS) from Gram-negative bacteria caused fibrinogen clotting to lead to the formation of an amyloid form of fibrin. We here show that the broadly equivalent lipoteichoic acids (LTAs) from two species of Gram-positive bacteria have similarly (if not more) potent effects. Using thioflavin T fluorescence to detect amyloid as before, the addition of low concentrations of free ferric ion is found to have similar effects. Luminescent conjugated oligothiophene dyes (LCOs), marketed under the trade name AmytrackerTM, also stain classical amyloid structures. We here show that they too give very large fluorescence enhancements when clotting is initiated in the presence of the four amyloidogens (LPS, ferric ions and two LTA types). The staining patterns differ significantly as a function of both the amyloidogens and the dyes used to assess them, indicating clearly that the nature of the clots formed is different. This is also the case when clotting is measured viscometrically using thermoelastography. Overall, the data provide further evidence for an important role of bacterial cell wall products in the various coagulopathies that are observable in chronic, inflammatory diseases. The assays may have potential in both diagnostics and therapeutics.