Figure 5

Regulation of surface CD3 levels on 3A9 TCR transgenic thymocytes on the B10^k and NOD^k genetic backgrounds. 3A9 TCR transgenic mice on the B10^k and NOD^k backgrounds were assessed for CD3 surface levels by flow cytometry, at both the DP and SP 1G12⁺ developmental stages. (a) Representative histograms for CD3 expression on DP cells and SP 1G12⁺ cells. B10^k mice are shown in grey, NOD^k mice in white. (b) The mean fluorescence intensity (normalized to B10^k SP 1G12⁺ thymocytes) and standard error is shown with B10^k in black and NOD^k in white (n = 7 for B10 values, 17 for NOD values). Significance of differences between B10^k and NOD^k groups of the same genotype are indicated by t-test p values about the group. t-tests comparing SP 1G12⁺ thymocyte expression were tested using a two sided t-test of the hypothesis that NOD^k expression levels are different to '100'.