Primary human AML induces a p16-driven SASP in vivo. (A) Schematic of in vivo experiment in which 2 × 10⁶ primary AML cells (4 individual patient AML cells and 5 CD34 HPC) were injected into NSG mice. (B) Engraftment was measured by detecting human CD45 by flow cytometry. In the dot plot, each AML engraftment into NSG mice is shown for BM. (C) Representative gating strategy for BMSC cell (hCD45⁻, mCD45⁻, mCD31⁻, mTer119⁻, mCD105⁺, and mCD140a⁺) population that was sorted. (D) RNA analysis for p16 and p21 in the sorted BMSC (hCD45⁻, mCD45⁻, mCD31⁻, mTer119⁻, mCD105⁺, and mCD140a⁺) isolated from NSG mice engrafted with primary human AML or cord blood CD34⁺ HPC. (E) RNA analysis for SASP in the sorted BMSC. (F) RNA analysis for lamin B in the sorted BMSC. (G) Terminal peripheral blood samples were taken and plasma isolated from all NSG mice engrafted with primary human AML or cord blood CD34⁺ HPC and mouse IL-6 was measured by enzyme-linked immunosorbent assay. The Mann-Whitney U test was used to compare between treatment groups (*P < .05). FSC, forward scatter; SSC, side scatter.