ML / TK test
The ML / TK test is a gene mutation test in mammalian cells . In this test, the resistance of mouse lymphoma cells (ML) to the toxic thymidine analog trifluorothymidine (a substrate for thymidine kinase (TK)) is used for selection . After treating the cells with the test substance, they are first cultured in normal growth medium for a certain time. They are then transferred into a medium with the selection agent for several days before the mutant colonies that have grown are then finally counted . In order to determine the cytotoxic effect of the test substance, the survival rate of the cells in the medium without selection agents is also determined in parallel.