False-colour scanning electron micrograph (SEM) of Kupffer cells in the liver. Here, within a sinu- soid (blood channel, blue) of the liver, Kupffer cells (yellow, at right) are seen. Kupffer cells are a type of macrophage (scavenger) typically found in the liver sinusoids. They are capable of phagocytosis, whereby they trap and engulf foreign particles and substances. Note their long arm-like filopodia. As an organ the liver serves to clean the blood of microorganisms, toxins and waste, and in this process bile is produced. Kupffer cells play an important role in this breakdown process. Magnification: x4,150 at 6x7cm size. Magnification: x6,650 at 4x5 inch size.