Liver sinusoids are different from the rest of the body’s sinusoids since they have macrophage cells intercalated in between their endothelial cells. Kupffer cells have a different embryological origin, coming from the myeloid line in the reticuloendohelial system (also called mononuclear phagocyte system) and are related to the immune system. They first develop in the bone marrow and then migrate to the liver where they differentiate into Kupffer cells.