Abs and reagents. DX5-PE, CD43-PE (clone 1B11), CD11c-PE (clone HL3), CD8a-PerCp (clone 53-6.7), TCR-b-allophycocyanin (clone H57-597), IFN-c-allophycocyanin (clone XMG1.2), IL-12allophycocyanin (clone C15.6), and streptavidin-PE were purchased from BD Pharmingen (http://www.bdbiosciences.com/). CD8a-FITC (clone CT-CD8a) was purchased from Caltag (http://www.caltag.com/). Ki-67-FITC (clone MM1) was purchased from Novocastra (http://www. vision-bio.com/). Purified rat anti-mouse IFN-a (clone F18 and RMMA-1) and anti-IFN-b (clone RMMB-1) were purchased from TEBU-Bio (http://www.tebu-bio.com/). 120G8 mAb was provided by Schering-Plough (http://www.schering-plough.com/) and conjugated to Alexa Fluor-488 using a kit from Molecular Probes. Isotype controls for each mAb were purchased from the appropriate manufacturer. The following tetramers conjugated to PE were obtained through the NIH Tetramer Facility (Atlanta, Georgia, United States): H-2L(d)/IE-1( 168 YPHFMPTNL 176 ) and H-2D(d)/ m164( 257 AGPPRYSRI 265 ). The above-mentioned reagents were used for FACS analysis in this study.