(a) Activated partial thromboplastin time (aPTT) measurement of the anticoagulant activity of RNA aptamer RB006 (blue) in pooled normal human plasma demonstrates aptamer mediated clotting time extension occurs in a dose dependent manner. A max clotting time of ~125 seconds is observed, which is significantly above the normal clotting time of approximately 30 seconds. Data represent the mean ± SD of technical replicates (N=4 wells).
(b) aPTT measurements of human plasma clotting time in the presence of RB006 with or without anti-PEG IgG in the reaction. Decreases in aptamer mediated clot-time extension with increasing concentrations of monoclonal anti-PEG IgG (blue) provide evidence for antibody mediated inhibition of RB006 function. Data represent the mean ± SD of technical replicates (N=6 wells) pooled from triplicate experiments. *** denotes p-value < 0.001, using t-test against aptamer only (1:0) (black).
(c) aPTT measurements of human plasma clotting time in the presence of the unPEGylated control aptamer RB005 with or without anti-PEG IgG demonstrates no change in clotting time, suggesting that anti-PEG IgG only inhibits the function of PEGylated aptamer. Data represent the mean ± SD of technical duplicates.