Characterization of iHPs. (A) Schematic diagram of HSPC transplantation and iHP infusion experiments. (B) Timeline for experiments. (C) Representative flow cytometric dot plot and histograms showing expression of CD34 and CD90 (filled histogram) vs unstained control (empty histogram in iHPs; cells are gated on live CD45⁺ cells). (D) Colony-forming cell (CFC) potential of iHPs. Results are mean ± standard deviation for 3 independent experiments. (E) Representative flow cytometric experiment showing MHC class I and class II expression (filled histograms) relative to unstained controls (empty histogram) in iHPs before and after activation with interferon-γ (IFN-γ). Cells are gated on live CD45⁺ cells. LV, lentivirus; PB, peripheral blood.