Page 131 - IJB-10-5

International Journal of Bioprinting Liver printing: from structure to application

Figure 2. The position and cell types of the liver. (A) The position of the liver in the human body, and the structure of hepatic lobules. (B) Different types
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of cells in the liver, and their distribution within the hepatic lobules. Adapted with permission from MacParland et al. Abbreviation: NK, natural killer.

(TGF-β) signaling produced by hepatic stellate cells inhibits non-alcoholic fatty liver diseases, hepatotropic infections,
hepatocyte DNA synthesis, which is blocked during the and genetic disorders. Liver transplantation is a life-
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proliferation phase 54–56 (Figure 3B). Miyaoka et al. also saving treatment and is considered the gold standard for
indicated that cellular hypertrophy plays an important role treating metabolic disorders and end-stage liver failure. In
in liver regeneration. In mice, the liver weight started to China, the total number of liver disease patients exceeds
increase from the first day after a 70% PHx and reached 300 million, with over 1 million deaths annually from
a plateau by day 7. Regeneration after a 30% PHx was end-stage liver disease. However, due to a severe shortage
achieved solely through hypertrophy without cell division, of donor organs, the number of patients receiving liver
and hypertrophy preceded proliferation following a 70% transplants in China does not exceed 6000 per year.
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PHx. Both proliferation and hypertrophy contributed Therefore, there is an urgent need to develop alternative
almost equally to regeneration after a 70% PHx. 57 strategies for liver transplantation.
3.The development process of 3.1. Xenotransplantation and
liver manufacturing hepatocyte transplantation
Xenotransplantation is recognized as a promising method
Every year, over 2 million people lose their lives due to liver- to address the shortage of donor organs. This technique
related diseases, which account for 4% of global mortality. involves transplanting organs from other species into
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Factors contributing to hepatocyte damage and decreased humans. Pig organs, in particular, are similar to human
liver function include drug-induced toxicity, alcoholic and organs in terms of size and function. Pigs also reproduce

Volume 10 Issue 5 (2024) 123 doi: 10.36922/ijb.3819