Spontaneous and mutagen induced sister chromatid exchange (SCE) frequencies have been studied in nine patients with multiple sclerosis and in nine age and sex matched healthy controls. The incidence of spontaneous SCE in lymphocytes of the MS patients was significantly greater, by about 50%, than in those of the control subjects. When exposed to mitomycin C (MMC) or ethyl methane sulfonate (EMS...

Antigenic variants were derived from a mutagen-treated, apparently nonimmunogenic fibrosarcoma of strain 2 guinea pigs. Fibrosarcoma line 107C3, originally induced by exposure of fetal cells to a chemical mutagen, was treated in vitro with the same mutagen. Cells that survived mutagen treatment were cloned, and the clones were tested for growth in soft agar, in conventional and immunosuppressed...

Mutagens dispersed in ecosystems are usually in low concentration and episodic in occurrence. The possibility of detecting such dispersed mutagens by utilizing indigenous bioconcentrator organisms coupled with a microbial mutagen assay offer a useful screening protocol. There are numerous examples of plant and animal species which concentrate toxic substances from the environment. Body extracts...