Attenuated T Cell Responses to a High-Potency Ligand In Vivo
Figure 6
In vivo activation status of 5C.C7 T cells stimulated with the high-affinity ligand K5 peptide.
Naïve 5C.C7 RAG2−/− CD45.1 T cells were adoptively transferred and activated by immunization with the indicated peptides and LPS. (A) Lymph node CD4+ T cells were stained for PD-1 at day 2.5 and day 6 (CD4+CD45.1+ gated). The day 2.5 histograms represent samples pooled from four or five mice. The black histogram corresponds to cells stimulated with LPS alone. Graphed PD-1 MFIs are from day 6, error bars show mean ± s.d., n = 3 mice. (B) Annexin V staining on CD4+ T cells from day 6 lymph nodes. (C) Day 2.5 lymph node samples were fixed immediately after harvest, methanol permeabilized, and stained with antibodies to phosphorylated Akt (S473) and phosphorylated Stat3 (Y705). Histograms are gated on CD4+CD45.1+ cells and represent samples pooled from four or five mice. Percent of 5C.C7 T cells positive for annexin V, pAkt, or pStat is shown on the plots and histograms. The data are representative of three independent experiments.