Laser scanning cytometry (LCS) allows detailed analysis of the cell cycle in PI stained human fibroblasts (TIG‐7)

Abstract

Abstract We have demonstrated a method for the in situ determination of the cell cycle phases of TIG‐7 fibroblasts using a laser scanning cytometer (LSC) which has not only a function equivalent to flow cytometry (FCM) but also has a capability unique in itself. LSC allows a more detailed analysis of the cell cycle in cells stained with propidium iodide (PI) than FCM. With LSC it is possible to discriminate between mitotic cells and G 2 cells, between post‐mitotic cells and G 1 cells, and between quiescent cells and cycling cells in a PI fluorescence peak (chromatin condensation) vs. fluorescence value (DNA content) cytogram for cells stained with PI. These were amply confirmed by experiments using colcemid and adriamycin. We were able to identify at least six cell subpopulations for PI stained cells using LSC; namely G 1 , S, G 2 , M, postmitotic and quiescent cell populations. LSC analysis facilitates the monitoring of effects of drugs on the cell cycle.