CD3D and acute lymphoblastic leukemia: The effects of CD3 KD on surface TCR levels were also analyzed in primary T cells and T-cell lines other than Jurkat E6-1 (Jurkat CH7C17 and HPB-ALL), and the results were comparable to Jurkat E6-1 T cells (Figure 7), further supporting that CD3γ and CD3δ are required for normal surface TCR expression in mature T cells.