Cyclooxygenase 2 (COX-2) is a 72 kDa protein that has been cloned from a variety of species including human, mouse, rat, and ovine. This preparation of COX-2 microsomes was prepared by solubilization and dilution of the 100,000 x g pellet from the lysate of cytokine-stimulated mouse macrophage cultures. Cayman’s preparation of mouse macrophage microsomes is a ready-to-use sample for SDS-PAGE. As such, it is an excellent positive control for the following Cayman Chemical polyclonal antibodies: Item Nos. 160106, 160126, 160116, and 101750.