Quantitative study of radiation effects in phytohaemagglutinin-stimulated leukocyte cultures.

Abstract

SummaryEffects of x-irradiation (up to 1500 R) have been quantitatively studied in human peripheral blood leukocyte cultures, with and without PHA stimulation, by electronic enumeration and sizing of cell nuclei. Without PHA a dose-dependent reduction of lymphocytes was seen, which was less marked than that resulting from in vivo irradiation. In studying the differential effect of irradiation on blast forms and cell division in PHA-stimulated cultures, vinblastine sulphate was used to arrest cell division. A dose-dependent effect was noted on both blast formation and cell division, but the effect on cell division was much greater. Cultures irradiated after blastogenesis had occurred also showed that the blast forms were not nearly so much affected as was further cell division. Labelling with tritiated cytidine in both irradiated and unirradiated cultures resulted in blast forms that were more heavily labelled than the non-transformed cells. This suggested that the metabolically more active cells were the ...