Expression of various molecules described in the text was analyzed via flow cytometry as previously described [16 (link)]. T cells from activation assays were collected on an LSR II BD Biosciences flow cytometer, (Franklin Lakes, NJ). Cells from migration and expression assays were collected on an Accuri C6 benchtop flow cytometer (BD Biosciences, San Jose, CA). All Abs were specific for mouse molecules. Abs to CD80 (clone 1G10), CD86 (clone GL1), MHC class I (clone AF6-88.5.5.3), and MHC class II (clone M5/114) were purchased from Ebioscience (San Diego, CA). Abs specific for Integrin β2, l-Selectin, CXCR4, CCR7, and CXCR5 were obtained from R&D Systems (Minneapolis, MN). Abs specific for CD8a (clone 53-6.7), CD4 (clone GK1.5), CD49d (clone 9F10), CD11a (M17/4), CD90.2 (clone 30-H12), CD25 APC (clone PC61.5), and CD44 (clone BJ18) were purchased from Biolegend (San Diego, CA). Anti-CD45 (clone 30-F11), CD19 (clone 1D3), and anti-CD69 (clone FN50) mAbs were purchased from Ebioscience. Data were analyzed with FlowJo software (Tree Star, Ashland, OR).