β₂ integrins are required for skin homing of primed T cells but not for priming naive T cells
J. Clin. Invest. Stephan Grabbe, et al. 109:183 doi:10.1172/JCI11703 [Go to this article.]

Figure 6
Hapten-specific activation of regional LN cells. Regional LNs were obtained from DNFB-sensitized mice 3 days after sensitization. (a) Fold increase in LN cells after sensitization with either vehicle only (0% DNFB), 0.1%, or 0.5% DNFB. (b) Hapten-specific proliferation of LN cells in response to either the specific hapten, DNBS, or a control hapten, FITC. Thy-1.2⁺ T cells were generated from LN cells and cultured together with hapten-coupled DCs for 72 hours, and then pulsed with ³H for an additional 18 hours. Due to the different proliferative capacities of CD18^–/– and CD18^+/+ T cells, a proliferation index was calculated as cpm after stimulation with hapten-exposed DCs, divided by cpm after stimulation with untreated DCs. A proliferation index greater than 1 indicates hapten-specific T cell proliferation. Inset: Allogeneic mixed lymphocyte reaction with purified T cells from CD18^–/– or CD18^+/+ mice as responders, and various numbers of allogeneic DCs (156–20,000) as stimulators. (c) Hapten-specific T cell activation as measured by upregulation of the activation marker CD69. Numbers in boxes indicate the percentage of CD69-expressing cells among the CD4⁺ and CD8⁺ T cells.