Evidence that alkaline phosphatase from human neutrophils is the same gene product as the liver/kidney/bone isoenzyme.

Neutrophils were isolated in good yield from fresh whole blood and their alkaline phosphatase was solubilized. Inhibitor studies using L-phenylalanylglycylglycine, L-phenylalanine and L-homoarginine revealed a distinct pattern of inhibition for each of the crude or purified preparations of the human isoenzymes of alkaline phosphatase from liver, intestine or placenta. Aqueous solutions from butanol extracts of human neutrophils and a purified preparation of the enzyme from neutrophils displayed a pattern virtually identical to that of the liver alkaline phosphatase. This is consistent with the proposal that it is the product of the same structural gene which codes for the liver/kidney/bone group of human alkaline phosphatases.