Abstract
Human placental (hPLAP) and germ cell (PLAP-like) alkaline
phosphatases are polymorphic and heat-stable enzymes. This study
was designed to develop specific immunoassays for quantifying
hPLAP and PLAP-like enzyme activity (EA) in sera of cancer
patients, pregnant women, or smokers. Polyclonal sheep anti-hPLAP
antibodies were purified by affinity chromatography with whole
hPLAP protein (ICA-PLAP assay) or a synthetic peptide (aa 57–71)
of hPLAP (ICA-PEP assay); the working range was