Enzyme-Linked Immunosorbent Assays for Biomarker Quantification

Enzyme-Linked Immunosorbent Assays (ELISA) were performed for the quantification of serum biomarkers. The manufacturer’s protocol was followed for each of the following ELISA Kit: Human IL-6 ELISA (Abcam), Human MMP2 ELISA (Abcam), Human MMP9 ELISA (Abcam), Human Myeloperoxidase (MPO) ELISA (Abcam), Human Topoisomerase II beta ELISA (MyBioSource). ELISAs were also performed for human cardiac troponin I (Abcam) and human cardiac Troponin T (MyBioSource). These assays were performed in a specific manufacturer provided antigen coated 96-well plate and at the end of protocol, the plate was read at 450 nm wavelength, in BioTek ELx900 Absorbance Reader^{12 (link)}. The standard curve was generated by plotting concentration of standards (x-axis) against corresponding absorbance (O.D value) of the standard (y-axis), as a XY-scatter plot to get 8-point curve. A linear trendline was added to the graph to achieve line of best fit with coefficient of determination (R² value) of ≥ 0.98. The concentrations for each biomarker in each sample was calculated using the resulting equation from the line of best fit, as describe previously^{12 (link),41 (link),42 (link)}.