Published online Dec 15, 1996. doi: 10.3748/wjg.v2.i4.212
Revised: September 12, 1996
Accepted: October 22, 1996
Published online: December 15, 1996
AIM: To study the effect of hypothermia on structure of membrane proteins of pig hepatocytes and the mechanism of transplantation of cryopreserved porcine hepatocytes in treating acute hepatic failure in Wistar rats.
METHODS: Isolated porcine hepatocytes were cryopreserved in liquid nitrogen for 150 d and then transplanted to the rat abdominal cavity. Three days later, 80% of rat liver by weight was resected. Conformation of membrane proteins of the porcine hepatocytes, liver function and weight of the remaining liver in the rats were measured.
RESULTS: Viability of the cryopreserved hepatocytes was 78%. Light and electron microscopy showed that the hepatocytes were morphologically intact. The cells were rich in glycogen and glucose-6-phosphatase. The α-helix content in the membrane proteins of fresh cells was 48%. After freezing the cells, the content was increased to 59.5%. Survival rate of rats in the transplanted group was 16/17, significantly higher than 3/9 in the control group (P = 0.0022). However, there were no significant differences in the weight of the remaining liver or indices of liver function between the two groups.
CONCLUSION: Transplant of frozen porcine hepatocytes is effective in treating acute hepatic failure. The mechanism is suggested to be a result of multiple effects. Hypothermia could increase α-helix content in the cellular membrane proteins, which might be related to the report that hypothermia was able to reduce the immunogenicity of the transplanted tissues and cells.