DEK-targeting DNA aptamer restores the function of BM CD34 ⁺ cell from FA patients. (A) Representative images show fluorescence staining of biotin-labeled DTA-64 (green) in HSCs (CD48⁻CD150⁺LSK) derived from WT C57BL/6J mice using streptavidin-FITC. Nuclei were visualized using DAPI staining (blue). HSCs were treated with 0.5 μM DTA-64 or biotin-labeled DTA-64 for 6 h. Scale bar: 5 µm. The right graph shows the distribution of biotin-labeled DTA-64 in nucleus by analyzing the MFI of nuclear and cellular biotin-labeled DTA-64 (n = 50 cells). (B) Representative heatmaps and line plots show DEK CUT&Tag peaks ± 5 kb from TSS in HSCs (CD48⁻CD150⁺LSK) from Dek^Tg mice. HSCs were administrated with the indicated aptamers and cultured for 48 h, followed by DEK CUT&Tag-seq. (C) Statistics and quantification of DEK CUT&Tag signal in HSCs (n = 2 samples per group). (D) The bar graph shows the cell viability of HSPCs using an MTT assay (n = 4 samples per group). Freshly sorted HSPCs (Lin⁻c-Kit⁺) from Fancd2^+/+ and Fancd2^−/− mice were administrated with the indicated aptamers, followed by treatment with DMSO or HU (100 μM) for 48 h. (E) Representative images of CFU-derived colonies from BM CD34⁺ cells (derived from healthy-3 and FA patient-1) under indicated conditions. Scale bar: 1,000 µm. The right bar graph shows the colony number (n = 3 samples per group). (F) Experimental schematic. BM CD34⁺ cells from two patients with FA were administrated with the indicated aptamers and cultured for 48 h. Then a total of 2 × 10⁴ CD34⁺ cells were injected in the tail of sublethally irradiated (2.0 Gy) immunodeficient NSG mice. (G) The right bar graph shows the donor chimerism in BM of the recipient mice at 16 wk after transplantation (n = 5 recipient mice per group). BM CD34⁺ cells from patient-5 were used for this experiment. The left chart shows the donor (hCD45⁺) chimerism in PB of the recipient mice at indicated time points after transplantation (n = 5 recipient mice per group). (H) The donor chimerism in PB and BM of the recipient mice were analyzed (n = 5 recipient mice per group). BM CD34⁺ cells from patient-6 were used for this experiment. (I) qRT-PCR analysis and the bar graph shows the expression of DEK gene in transduced HSCs (n = 5 samples per group). (J) Representative flow plots show p-ATR staining in transduced HSCs. The right bar graphs show the MFI of p-ATR and p-CHK1 in HSCs (n = 5 samples per group). (K) The bar graph shows the frequency of EdU⁺ cells in HSCs (n = 5 samples per group). The data presented in panels A–K are representative of two independent experiments. The results shown in panel C illustrated as violin plots, and other panels are shown as mean ± SD. Statistical analyses were performed using a two-tailed unpaired Student’s t test for panel C and one-way ANOVA followed by Tukey’s post hoc test for panels D–K. P values are presented as follows: *P < 0.05, **P < 0.01, and ***P < 0.001; n.s., not significant.