Figure 4

Technical replication on subsequent array versions. (A) Experimental analysis for the T_reg data set: FACS analysis and sorting windows of CD4⁺ CD127^low CD25⁺ T_reg cells and CD4⁺ CD127⁺ CD25^- T_conv cells (left). Expression of FOXP3 in the respective T cell subsets was assessed by flow cytometry (middle) and quantitative RT-PCR (right). Boxplots were used to compare the dynamic range of signal intensities on the arrays for (B) the T_reg data set and (C) the whole blood data set. Only signals for the 8299 identical oligonucleotides were used. Technical replicates were checked both by principle component analysis based on the 100 most variable genes for (D) the T_reg data set and (E) the whole blood data set as well as hierarchical cluster analysis (see Additional file 11).