Quantitative comparison of the cytogenetic effect of thiophosphamide during in vivo and in vitro action on monkey lymphocytes

: Mutagenic in vivo and in vitro effects were compared quantitatively by the investigation of sister chromatid exchange (SCE) rate and chromosomal aberrations caused by thiophosphamide in macaca rhesus lymphocytes. The integral of thiophosphamide concentration in the blood or culture fluid by a certain time period was used for the estimation of the dose of mutagenic exposure. It was shown that the dose-response relationships and corresponding regression coefficients were similar when the in vivo and in vitro results were compared. The data obtained indicate the possibility for quantitative extrapolation of the results obtained in vitro on the entire organism.