Lipoprotein-associated phospholipase A2 (Lp-PLA2) also known as platelet-activating factor acetylhydrolase (PAF-AH) is a phospholipase A2 enzyme in humans. Lp-PLA2 is a 45 kDa protein of 441 amino acids encoded by the PLA2G7 gene. Two highly selective anti-human Lp-PLA2 monoclonal antibodies were recently developed by Creative Diagnostics, which make possible the development of highly sensitive and rapid sandwich immunoassays. Our in-house assays have a linear detection range from 0.13 to 1000 ng/mL. All recommended MAb combinations were evaluated in medium-scale clinical trials with blood samples from normal and patients with atherosclerosis or cerebral infarction.
1. Calibration Curve
All MAbs were tested in pairs as capture and detection antibodies to select the best two-site MAb combinations for the development of a quantitative sandwich immunoassay. Calibration curves for several best two-site combinations, which utilized different anti Lp-PLA2 MAbs, are shown in Fig.2. Detection antibodies were labeled with horse reddish peroxidase (HRP). The best selected MAb combinations for the development of quantitative human Lp-PLA2 immunoassays are (capture-detection respectively) :
Mab combination A: DMAB-SP01—DMAB-SP02
Mab combination C: DMAB-SP02—DMAB-SP01
A certain amount of excellent Lp-PLA2 protein (Cat: DAG-SP1) is also offered by Creative Diagnostics as liquid. The purity of the Lp-PLA2 protein was over 90%, it could be used as calibrator in immunoassay.