Figure 5.

CD80 and CD86 interactions with CD28 induce antigen-specific CD4⁺ T cell proliferation in the renal draining node. Illustrative single-parameter histograms (A) show that 72 h after OVA, substantial proliferation of OT-II cells is seen in mice given control Ab, but proliferation is almost abrogated after functional inhibition of CD80 and CD86, demonstrated by total numbers of OT-II cells (B) and the numbers of cells in each division (C). In addition, of the few OT-II cells still present in anti-CD80–and anti-CD86–treated mice, the highest proportion were in divisions 3 and 4 (versus division 6 for control Ab–treated mice), suggesting a delay in the onset of rate of proliferation in the absence of CD80 and CD86 (D). The dotted vertical lines in the single-parameter histograms (A) represent the degree of CFSE intensity of nonproliferating cells. (B and C) □, Mice injected with control Ab; ▪, mice injected with anti-CD80 and CD86 Ab.