Ito cells

ito cells or hepatic stellate cells

1. Ito cells Soroush Sarmadi “Shiraz university” “Faculty of veterinary medicine” “Department of clinical science”

2. Liver histology

3. Ito cells -The other cell type found in the peri-sinusoidal space is the hepatic stellate cell or Ito cell. -Ito cells are located in the liver in the space of Disse .

4. Electron micrograph of two hepatic sinusoids of the liver:

5. Ito cells - These cells of mesenchymal origin. -Primary storage site for hepatic vitamin A. -Vitamin A is released from the hepatic stellate cell as retinol (alcohol form) bound to retinol-binding protein (RBP) . -It is then transported from the liver to the retina, where its stereoisomer 11- cis -retinal binds to the protein opsin to form rhodopsin , the visual pigment of rods and cones of the retina.

6. Retinol-binding protein -Retinol-binding proteins  (RBP) are a family of proteins with diverse functions. -They are carrier proteins that bind retinol.  -RBP is synthesized within the liver. -secretion being dependent upon retinol concentrations.

7. Ito cells -In certain pathologic conditions, such as chronic inflammation or liver cirrhosis , hepatic stellate cells lose their lipid and vitamin A storage capability and differentiate into cells with characteristics of myofibroblasts . -they synthesize and deposit type I and type III collagen within the peri-sinusoidal space, resulting in liver fibrosis. -hepatic stellate cells play a role in remodeling the extracellular matrix during recovery from liver injury.

8. Ito cell

9. Thanks for your attention