Hepatic stellate cell in the cell body store vitamin A as retinol ester. The function and role of quiescent hepatic stellate cells is unclear. Recent evidence suggests a role as a liver-resident antigen-presenting cell, presenting lipid antigens to and stimulating proliferation of NKT cells. When the liver is damaged, stellate cells can change into an "activated" state. The activated stellate cell is characterized by proliferation, contractility, and chemotaxis. This state of the stellate cell is the main source of extracellular matrix production in liver injury. This attribute makes it a key factor in the pathophysiology of the liver. The amount of stored vitamin
British Institute of Organ Studies British Institute of Organ Studies The British Institute of Organ Studies, more commonly known by its acronym BIOS, is a British organisation and registered charity which aims to promote study and appreciation of all aspects of the pipe organ. Further, it acts as a lobbying body to raise awareness of organ issues with appropriate statutory bodies. Membership is open to all. The aims of BIOS are BIOS publishes a quarterly Reporter newsletter and magazine and a yearly Journal which contains articles on organ history. BIOS is also responsible for the National Pipe Organ Register (NPOR), which aims to catalogue all