Liver sinusoidal endothelial cell

Liver Sinusoidal Endothelial Cell (LSEC) is a specialized type of endothelial cell found in the liver. These cells line the sinusoids of the liver and play a crucial role in the filtration and clearance of blood, as well as in the regulation of immune responses.

Structure

LSECs are unique among endothelial cells due to their fenestrated structure. They possess numerous small pores, or fenestrae, which allow for the exchange of molecules between the blood and the liver parenchyma. These fenestrae are grouped into sieve plates and lack a basement membrane, which further facilitates the exchange of substances.

Function

LSECs perform several important functions in the liver:

• Filtration and Clearance: LSECs filter the blood that flows through the liver, removing harmful substances and waste products. They also play a role in the clearance of lipoproteins and glycoproteins from the circulation.

• Immune Regulation: LSECs are involved in the regulation of immune responses in the liver. They can present antigens to T cells, contributing to the immune surveillance of the liver.

• Liver Regeneration: LSECs produce growth factors such as vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF), which promote the regeneration of liver tissue.

Clinical Significance

Alterations in the structure and function of LSECs have been associated with several liver diseases, including cirrhosis, hepatitis, and liver cancer. For example, in cirrhosis, the fenestrae of LSECs can become defenestrated, impairing the filtration function of these cells and contributing to the progression of the disease.

Research

Research on LSECs is ongoing, with a focus on understanding their role in liver disease and exploring their potential as therapeutic targets. For example, strategies to restore the fenestrated structure of LSECs are being investigated as a potential treatment for cirrhosis.

See Also

• Liver
• Endothelial cell
• Sinusoid (blood vessel)
• Liver disease