Liver removes unwanted cells through apoptosis

Sometimes, cells are no longer needed or no longer functional in the liver. They are removed through a genetically programmed form of cell death called apoptosis. Apoptosis occurs during embryonic development and later in order to remove senescent, damaged, genetically mutated, or virus infected cells.

  • To be healthy, the adult liver maintains a constant amount of cells, so the number eliminated by apoptosis cells equals the number of cells generated by mitosis. This allows the proper liver homeostasis. Prompt “physiological” apoptosis allows the clearance of cells with almost minimal immune response.
  • Apoptosis occurs in several steps of destruction of the exterior and interior of cells. It is orchestrated by the massive activation of internal enzymes, proteases and endonucleases, which gradually destroy cells. Cells shrink, causing their plasma membrane to bleb. Genomic material (chromatin) consisting of a complex of DNA, protein and RNA undergo condensation. DNA fragments and cellular proteins degrade.
  • Finally, cell fragments into membrane bound vesicles named apoptotic bodies. Apoptotic bodies enter into special “eating cells” of the liver called Kupffer cells. They digest apoptotic bodies through a process called phagocytosis.

  • Author of the text and the illustration: Iryna Ilkavets
    Comprehensibility: 
    No votes yet
    (1=bad 5=excellent)