Impact of bispecific CAR-iNKT cells on hematopoiesis in humanized mice. (A) Schematic of xenograft experiment to test hematologic toxicity of CD19-CD133 CAR-iNKT cells in vivo. (B) Peripheral blood human CD45 engraftment levels in mice treated with phosphate-buffered saline (PBS; n = 5) or 10⁷ CD19-CD133 CAR-iNKT cells (n = 7). (C) Peripheral blood human CD19⁺ cells in mice treated with PBS (n = 5) or 10⁷ CD19-CD133 CAR-iNKT cells (n = 7), in 2 separate experiments, showing a transient drop in B-cell proportions 1 to 3 days after CAR injection. Unpaired t test; ∗P < .05. (D) Long-term engraftment in the BM of mice treated with PBS or 10⁷ CD19-CD133 CAR-iNKT cells. From left to right: proportion of hCD45 cells in BM (PBS, n = 4, CAR, n = 6); B cells, T cells, and myeloid cells in the BM expressed as proportion of hCD45⁺ cells (PBS, n = 4, CAR, n = 6); and immature CD34⁺ cells in the BM expressed as proportion of hCD45⁺ cells (PBS, n = 4, CAR, n = 5). Median denoted by solid lines, and dashed lines denote quartile distribution within the sample set. ns, not significant.