Open AccessCell kinetic effects of incorporated 3 H‐thymidine on proliferating human lymphocytes: Flow cytometric analysis using the DNA/nuclear protein method
Author(s) -
Pollack A.,
Moulis H.,
Greenstein D. B.,
Block N. L.,
Irvin G. L.
Publication year - 1985
Publication title -
cytometry
Language(s) - English
Resource type - Journals
eISSN - 1097-0320
pISSN - 0196-4763
DOI - 10.1002/cyto.990060507
Subject(s) - thymidine , propidium iodide , nuclear protein , nuclear dna , mitosis , flow cytometry , dna , microbiology and biotechnology , biology , fluorescein isothiocyanate , chemistry , fluorescence , biochemistry , apoptosis , transcription factor , physics , quantum mechanics , programmed cell death , gene , mitochondrial dna
Phytohemagglutinin‐stimulated human peripheral blood lymphocytes incorporating high concentrations of 3 H‐thymidine accumulate in G2 and show a consequent reduction in the number of cells entering M (division delay). The simultaneous flow cytometric analysis of DNA content (propidium iodide fluorescence) and nuclear protein content (fluorescein isothiocyanate fluorescence) allows for the accurate quantitation of these events; G2 and M are separated in the bivariate distributions. A good correlation was observed between mitotic indices, quantitated by manually counting mitotic cells, and integration of the M area in DNA/nuclear protein histograms. Moreover, significant differences in G2 nuclear protein levels were found between untreated and 3 H‐thymidine‐treated lymphocytes. In order to characterize this effect, G2 was empirically divided into low nuclear protein (G2A) and high nuclear protein (G2B) compartments. 3 H‐thymidine caused an initial accumulation of lymphocytes in G2A, followed within 3–6 h by a gradual movement of some cells into G2B, with a subsequent accumulation of cells in G2B. The results suggest that the distribution of cells in G2 (G2A and G2B), the average nuclear protein content of G2B cells, and the proportion of cells in M are parameters that when used in combination provide a unique description of radiobiological effects.