Ectopic expression of Hsp70 enhances staurosporine- and TCR-induced apoptotic cell death in TAg-Jurkat cells. (A) Left panel: expression of Hsp70 protein in GFP transfectants (GFP-3 and -189) and GFP-Hsp70 transfectants (Hsp70-46 and -111) was analyzed by immunobotting using anti-Hsp70 Ab. Expression of RAN (ubiquitously and abundantly expressed Ras-related nuclear protein) was assessed for a loading control. Right panel: normal T cells or one of the Hsp70 transfectants (Hsp70-46) was stimulated with or without anti-CD3/CD28 Abs. Expression of Hsp70 or RAN was analyzed as above. (B-C) Transfectants (5 × 105 cells) were cultured in the absence or presence of various amounts of staurosporine (B) or stimulated with various doses of anti-CD3/CD28 Abs (C), and percentages of apoptotic cell deaths were determined by flow cytometry after propidium iodide staining. Each value represents the mean ± SD of 3 independent experiments. *P < .05; **P < .01.
