Functional Flexibility in T Cells Yasmina Laouar, I.Nicholas Crispe  Immunity  Volume 13, Issue 3, Pages 291-301 (September 2000) DOI: 10.1016/S1074-7613(00)00029-7

Figure 1 Predictable Expression of a Vα11+ Transgenic TCR in Radiation Chimeras Reconstituted with Different Proportions of TCR Transgenic (Thy-1.2+) and Nontransgenic (Thy-1.1+) Bone Marrow Data are from one representative experiment of ten with three mice/group/experiment. Immunity 2000 13, 291-301DOI: (10.1016/S1074-7613(00)00029-7)

Figure 2 Constraints on T Cell Proliferation In Vivo (A) Selective gates on TCR transgenic or nontransgenic cells in chimeras with a high (a) or low (b) frequency of TCR transgenic cells show that when T cells are abundant a subset proliferates (40% BrdU positive, in the example shown). When T cells are rare, all proliferate (97%). Nontransgenic cells show only background proliferation. (B) The frequency of proliferating cells (a) is inversely related to the TCR transgenic cell number, while the absolute number of proliferating cells (b) is positively correlated with cell number but approaches a limit of around 8 × 106 cells. (C) The TCR transgenic T cell number does not affect the number of DC ([a], closed circles). Treatment with Flt-3L increases the DC number around 5-fold in all groups of chimeras ([b], closed squares), but there is no effect on the inverse relationship between the number of TCR transgenic cells and the frequency of proliferating cells (compare [a] with [b], open symbols). Results represent the mean value for four mice per group. Immunity 2000 13, 291-301DOI: (10.1016/S1074-7613(00)00029-7)

Figure 3 Noncycling Ag-Specific T Cells Show Phenotypic Changes of Activated T Cells In saline (PBS)-injected control chimeras, nontransgenic T cells mostly expressed a naive phenotype, while TCR transgenic CD4+Vα11+ cells exclusively expressed a naive phenotype. Compare, in particular, CD44 and CD62L expression in the two PBS-treated groups. In PCC peptide–injected chimeras containing 90% of TCR transgenic cells, cycling and noncycling CD4+-Vα11+ cells were analyzed for activation markers on day 3. Data are from one representative experiment of five with two mice/group/experiment. Immunity 2000 13, 291-301DOI: (10.1016/S1074-7613(00)00029-7)

Figure 4 Noncycling Ag-Specific Cells Show Cell Cycle Arrest in G1 Cycling and noncycling CD4+Vα11+ cells generated upon PCC stimulation in chimeras containing 90% of TCR transgenic cells were analyzed for expression of cell cycle control proteins on day 3. The data show cytoplasmic staining for cyclin A, cyclin D3, p21cip-1, and an isotype-matched IgG control. The cell populations shown are control nontransgenic T cells (dotted lines), TCR transgenic BrdU+ large blast cells (thin solid lines), TCR transgenic small BrdU+ cells (dashed lines), and the TCR transgenic but BrdU negative cells (thick solid lines). The data show that the noncycling TCR transgenic cells contain elevated cyclin D3 but not cyclin A; therefore, they are in G1 phase of the cycle. Data are from one representative experiment of three with two mice/group/experiment. Immunity 2000 13, 291-301DOI: (10.1016/S1074-7613(00)00029-7)

Figure 5 Noncycling Ag-Specific Cells Are Able to Express Effector Cytokines Cycling and noncycling CD4+Vα11+ cells in chimeras containing 90% of TCR transgenic cells were analyzed for intracellular expression of effector cytokines. On day 3 after PCC/BrdU injections, transgenic (CD4+Vα11+) and nontransgenic (CD4+Vα11−) cells were analyzed for expression of IL-2, IFNγ, IL-4, and with an IgG isotype control in combination with BrdU. Data are from one representative experiment of five with two mice/group/experiment. Immunity 2000 13, 291-301DOI: (10.1016/S1074-7613(00)00029-7)

Figure 6 Chemotactic Activity of SLC and ELC Chemokines on Cycling and Noncycling Ag-Specific Cells Cycling and noncycling CD4+Vα11+ cells generated upon PCC stimulation in chimeras containing 90% of TCR transgenic cells were examined for their chemotactic response toward SLC and ELC chemokines. (A) On day 3, cells from PBS (open symbols) or peptide (closed symbols) treated chimeras were subjected to increasing concentration of SLC (circles) or ELC (squares) in a chemotaxis assay through 5 μm pore transwell filters. The number of migrated transgenic cells were determined by flow cytometry for 60 s under a constant sheath pressure with appropriate gates on CD4+Vα11+ cells. Results are expressed as the chemotactic index (see text). (B) Input and migrated cells toward SLC (1 nM) and ELC (1 nM) were stained with anti-CD4, anti-Vα11, anti-Thy1.2, and anti-BrdU. Results show BrdU verus FSC on gated CD4+Vα11+Thy1.2+ cells. The assay was done in triplicate and data are from one representative experiment of two. Immunity 2000 13, 291-301DOI: (10.1016/S1074-7613(00)00029-7)