Expression of CD4, CD90.1, CD3, and CD28 and TCR Vβ usage in SLP-76OST–edited and control CD4+ T cells. (A) After gating on live singlets, SLP-76OST–edited and control CD4+ T cells that were expanded for 34 d were analyzed by flow cytometry for the expression of CD4, CD90.1, CD3, and CD28. Numbers in dot plots and histograms indicate the percentage of cells within the specified gates and the percentage of positive cells, respectively. Data are representative of three independent experiments. (B) SLP-76OST–edited and control CD4+ T cells were expanded for AP-MS and analyzed using a panel of 24 TCR Vβ–specific antibodies. The clonogram shows that both populations have preserved a rather similar polyclonal Vβ repertoire. Data are representative of two independent experiments. FSC, forward scatter; SSC, side scatter.