Sandwich ELISA of Apolipoprotein A-1 was performed by coating wells of a 96-well plate with 100ul of an Apo A-1 rabbit monoclonal antibody diluted to a concentration of 1 µg/mL in carbonate/bicarbonate buffer overnight at 4C. Wells were blocked with 150ul of StartingBlock T20 (TBS) Blocking Buffer for 30 minutes, and 80ul of recombinant human Apo A-1 or recombinant mouse Apo A-1 was added to the plate at concentrations ranging from 1.6-1000ng/ml and incubated for 1 hour at room temperature. The plate was washed with 1X TBST, and 100ul per well of an Apo A-1 mouse monoclonal antibody was added to each well for 1 hour at room temperature. The plate was washed, and 100ul per well of an HRP-conjugated rabbit anti-mouse IgG cross-adsorbed secondary antibody was incubated for 30 minutes at room temperature. Detection was performed using 1-Step Ultra TMB Substrate, followed by Stop Solution. Absorbances were read on a spectrophotometer at 450-550nm.