Figure 2

Heat-induced immunostained luciferase proteins in bovine cells. Male X^LUCY (OV7060) and female XX^LUC(BSF731) transgenic fibroblast cells were fixed in cold methanol after continuous culture at 39°C or after 20 min at 45°C and 7 hours at 39°C. Immunostaining was performed with monoclonal mouse antibodies directed against the firefly luciferase and FITC-conjugated anti-mouse secondary antibodies (bright signal in left panels and green signal in right panels). Nuclear DNA was counterstained with Hoechst 3342 (blue signal on right panel). In these photographs (X400), 30 (97%) out of 33 OV7060 cells and 24 (82%) out of 29 BSF731 cells were counted positive after HS induction since they displayed a level of immunostaining two standard deviations above the mean value observed in untreated cells (see [additional File 2 Additional data]).