Inhibition of lymphocyte proliferation by liver arginase.
The activities of thymidine kinase and uridine kinase (enzymes for pyrimidine salvage pathway) in phytohemagglutinin (PHA)--prestimulated lymphocytes were inhibited by arginase in a similar pattern to the inhibition on thymidine incorporation. Further study revealed that arginase did not directly affect the activities of these enzymes in the cell-free system. Thymidine kinase and uridine kinase activities of PHA-prestimulated lymphocytes were inhibited by arginase making their activities as low as that cultured in arginine-free RPMI-1640 medium. These results suggest that arginine-depletion in the culture medium is the primary mode of action of arginase on the inhibition of mitogen-stimulated lymphocyte proliferation.
Huang
M H
MH
Department of Medicine, Veterans General Hospital-Taipei, Taiwan, ROC.
Yang
C C
CC
Wang
S R
SR
D000818:Animals; D001119:Arginase / Q000378:metabolism / Q000494:pharmacology*; D002474:Cell-Free System; D002478:Cells, Cultured; D003470:Culture Media; D006801:Humans; D008099:Liver / Q000201:enzymology*; D008213:Lymphocyte Activation / Q000187:drug effects*; D008214:Lymphocytes / Q000187:drug effects* / Q000201:enzymology; D051379:Mice; D013937:Thymidine Kinase / Q000037:antagonists & inhibitors; D014541:Uridine Kinase / Q000037:antagonists & inhibitors
D003470:Culture Media; D013937:Thymidine Kinase; D014541:Uridine Kinase; D001119:Arginase