Corning® Matrigel® Basement Membrane Matrix is a solubilised basement membrane preparation extracted from the Engelbreth-Holm-Swarm (EHS) mouse sarcoma, a tumour rich in extracellular matrix proteins. Its major components are laminin, followed by collagen IV, entactin, and heparin sulphate proteoglycan. It also contains growth factors that occur naturally in the EHS tumour. At room temperature, Corning® Matrigel® Matrix polymerises to produce biologically active matrix material resembling the mammalian cellular basement matrix. Corning® Matrigel® Basement Membrane Matrix is effective for the attachment and differentiation of both normal and transformed anchorage dependent epithelial and other cell types. The growth factor reduced (GFR) product is useful where a more highly defined basement preparation is desired.