Fig. 1. (A-H) Immunocytochemical analysis of AG05229 cells. (A-D) Cycling cells. (E-H) Cells at M1. The assays are: PC, phase contrast; p21, immunocytochemical detection of p21^Waf1; SAßgal, histochemical assessment of SAß-gal activity; TUNEL, assay for apoptosis. All cells except PC are counterstained with haematoxylin. Cell-based assays were done in triplicate. (I,J) FACS analysis histograms of cell number versus FL2-H for AG05229 and HCA2 cells at M1 (pulse height is a measure of DNA content). White bar, 100 µm (A,E); black bar, 100 µm (B-D,F-H).