[Application of in vitro micronucleus tests using L5178Y mouse lymphoma and WTK1 human lymphoblastoid cell lines to antimutagenicity assay].

In the in vitro micronucleus (MN) tests using L5178Y mouse lymphoma and WTK1 human lymphoblastoid cell lines, 2 well-known antimutagens, Vitamin C (Vc) and the sodium and copper salt of chlorophyll (Chl), were tested to evaluate their ability to inhibit the mutagenicity of mitomycin C(MMC). Three kinds of treatment were designed, namely the simultaneous treatment with Vc (or Chl) and MMC, the use of Vc (or Chl) before the use of MMC, and the use of Vc (or Chl) after the use of MMC. The results showed that Vc and Chl had no MN inductivity in the two cell lines; that simultaneous treatment with Vc and MMC and pre-treatment with Vc effectively reduced MMC-induced MN cell frequencies; and that simultaneous treatment and pre-treatment with Chl at dose level of 0.12 mg/ml, significantly reduced MMC-induced MN cell frequencies of L5178Y cells. The antimutagenic effect of Chl on WTK1 cells was found in simultaneous and pre-treatment at dose levels of 0.12 and 0.06 mg/ml.