CORESTA Congress, Kyoto, 2004, SSPOST 05
Genotoxicity of cigarette smoke condensate from different tobacco types in cultured human lymphocytes
Istituto Sperimentale per il Tabacco, Scafati, Italy
Smoke cigarette condensate (SCS) from different tobacco types was evaluated for genotoxicity in peripherical blood human lymphocyte cultures by Sister-Chromatid Exchange (SCE). Lymphocyte cultures were set up by adding heparinized whole blood to RPMI 1640 medium, supplemented with 15% heat inactivated fetal calf serum, and L-glutamine, without antibiotics. Lymphocytes were stimulated by 2% phytohemagglutinin. The cultures were incubated at 37 °C for 72 hs. 30 hours before harvesting, 5- bromo deoxyuridine (BrdU) was added and then, 2 hours before the end the culture period, colchicine. Slides were stained with acridine orange and metaphases were observed, 24 hours later, under a fluorescent microscope. To detect possible metabolic modification in genotoxicity of SCS, lymphocyte cultures for SCE assay were also performed in the presence and absence of S9 microsomal fraction, a metabolic activation system. Moreover smoke cigarette condensates genotoxicity of different tobacco types were compared with that of mitomycin C, an antibiotic inducing a great increase in the frequency of SCE. A significant difference in SCE frequency was observed among the SCS of the different tobacco types assayed and untopped Bright tobacco showed the lowest values. The presence of S9 microsomal fraction, in SCE tests, reduced genotoxic activity of both smoke cigarette condensates and mitomycin C. The effect of each smoke cigarette condensate assayed on SCE frequency was significantly lower than mitomycin C.