Figure 7. Frequency of self-antigen⁺ thymic antigen-presenting cells correlates with the responsiveness of the corresponding CD4⁺ T cell population.

(a) Contour plots of MHCII (I-A^b) and eGFP⁺ or eYFP⁺ expression by EpCAM⁺ thymic epithelial cells (left) and thymic dendritic cells (right) from the indicated members of Clusters 1–3. Plots are from 5 experiments. Numbers indicate the percent of cells that are I-A^b+ and either eGFP⁺ or eYFP⁺.

(b) Numbers of eGFP⁺ or eYFP⁺ EpCAM⁺ thymic epithelial cells in the indicated mouse strains, identified as in (a). Bars are colored according to the clusters identified in Figure 1d. Error bars represent the standard deviations. (n=3–6 total mice per group, * P<0.05, ** P<0.0005, *** P<0.0001, n.s. = not significant by one-way ANOVA of log₁₀ transformed data).

(c) Numbers of eGFP⁺ or eYFP⁺ thymic dendritic cells in the indicated mouse strains, identified as in (a). Bars are colored according to the clusters identified in Figure 1d. Error bars represent the standard deviations. (n=3–6 total mice per group, * P<0.05, *** P<0.0001, n.s. = not significant by one-way ANOVA of log₁₀ transformed data).

(d) Linear regression analysis of the log₁₀(number of eGFP⁺ or eYFP⁺ thymic antigen-presenting cells) versus log₁₀(number of tet⁺ CD4⁺ T cells 14 days after immunization). Each point represents values for an individual mouse strain as indicated. For each point, the y-axis value represents the log₁₀(geometric mean from Figure 1a), and the x-axis value represents the log₁₀(geometric mean for the total number of I-A^b+ eGFP⁺ or eYFP⁺ EpCAM⁺ thymic epithelial cells and dendritic cells for each strain). Circles and labels are colored according to the clusters identified in Figure 1d.