Purification of leukocytosis-promoting substance from bovine parotid gland extract

A leukocytosis-promoting substance was purified from a crude bovine parotid gland extract. The purified substance was proved to be a single component by polyacrylamide gel disc electrophoresis. It stimulates an increase of peripheral leukocyte numbers in rabbits. The molecular weight of the physiologically active component was estimated to be 4.5 · 10⁴, and the component was found by sodium dodecyl sulfate polyacrylamide gel electrophoresis to be dissociated into two subcomponents.