Developing Clone 5 thymocytes in animals constructed with DQ8+ HSCs show phenotypic characteristics of negative selection. Thymocytes were analyzed by FCM. Within each sample the cells are first gated into GFP+ and GFP- populations. All further analysis is conducted on both populations separately, treating the GFP- population as an internal control within each mouse. a. Comparison of the percentage of CCR7+ CD4SP in total GFP+ and GFP- thymocytes within the same mouse transplanted with Clone 5 or GFP-only transduced cells. b., c. Representative staining of grafted thymi of mice transplanted with b. DQ8+ HSCs c. DQ8- HSCs. Cells are gated on GFP expression, then on CD4SP prior to analysis of CCR7 expression. n = 3 Clone 5 DQ8-, n = 4 Clone 5 DQ8+, n = 2 GFP-only DQ8-, n = 3 GFP-only DQ8+. ∗ = p < 0.05 by paired t-test. Mice marked with a circle are transgenic for HLA-DQ8.