Anti-Hsp90 treatment leads to inhibition of T-cell proliferation ex vivo. Draining lymph node cells were isolated from GST-mCVIIC–immunized mice 6-8 weeks after immunization and reactivated with anti-CD3 (2.5 μg/mL) and anti-CD28 (1 μg/mL) antibody, or the recombinant autoantigen His-mCVIIC (50 μg/mL). Incubations were performed in the absence or presence of different amounts of 17-DMAG (A-B) or TCBL-145 (C-D), and T-cell proliferation was determined by BrdU ELISA. Dotted lines represent the values obtained from cells incubated with medium alone. Values are means ± SEM of 6 mice per group. *P < .05.