Arginase 1, Human, mAb D1.2

Monoclonal antibody D1.2 reacts specifically with Arginase I, the final enzyme in the urea cycle, which is responsible for the hydrolysis of arginine to urea and ornithine. The highest concentration of the enzyme is present in the liver in which the bulk of ureagenesis occurs. Two types of arginases are known: Arginase I and II. The cytosolic enzyme found primarily in liver is Arginase I, a 35 kD protein that circulates as trimer. Arginase II is exclusively located in the mitochondrion. Arginase I is next to the liver in man also expressed by mature fetal and adult red blood cells and activated monocytic cells. During inflammation induction of Arginase I by inflammatory cytokines in monocytic cells is considered to lead to a local depletion of arginine resulting in a microenvironment that prevents nitric oxide production and arginine dependent T cell function. Arginase II is expressed by kidney, nucleated red blood cells, brain, spinal cord, gastro-intestinal tract, mammary gland and prostate. Enhanced circulating Arginase I levels have been reported after surgery, following haemorrhage and in asthmatic patients. Measurement of circulating Arginase I has been used experimentally as rapid marker for liver injury.