The liver is composed of five major cell types. Hepatocytes comprise approximately 70% of the liver cell population and are responsible for most metabolic and hormonal processes. The other four cell types, collectively known as hepatic non-parenchymal cells, consist of resident macrophages called Kupffer cells, stellate cells, liver sinusoidal endothelial cells, and cholangiocytes. These cells serve to support the liver structure, transport molecules in and out, and communicate with the immune system.
Creating More Complex Liver Models
Using primary liver non-parenchymal cells in co-culture with each other and with hepatocytes can enable a more predictive cell culture model for liver toxicity and disease. For example, the ability now to create in vitro models that co-culture hepatocytes with Kupffer cells, the liver resident macrophage, can improve the ability to detect immune mediated complex toxicities. Other new models such as co-cultures with stellate and liver endothelial cells, in both monolayer and 3D spheroid models, have also been shown to increase the predictive power of cell culture models.