Fig. 4.

TPM1 deficiency enhances iPSC-derived hematopoietic progenitor cell formation. a A 5-kb region (TPM1 exons 4–8, red box) was targeted for CRISPR/Cas9-mediated deletion to create KO iPSCs. b Western blots showing TPM1 protein expression at the indicated differentiation days. c Western blots showing TPM1–4 expression in wild type (WT) and KO iPSCs, hematopoietic progenitor cells (HPC, differentiation d8), and FACS-sorted MKs (CD41⁺/CD42b⁺, expansion d3). TPM1 antibodies targeted exon 4 (top) or exon 9d (2nd panel). d Primitive streak and mesoderm gene expression are normal in differentiating KO iPSCs. e, f KO cells yield e KDR⁺/CD31⁺ cells and f CD43⁺ hematopoietic progenitor cells (HPC) with normal kinetics, but in enhanced abundance. Percent (%) cells within boxed regions for WT and KO clone 2 are shown from a representative experiment. g Quantification of WT and KO non-adherent HPCs on differentiation day 8. Bars represent fold change in HPCs (mean ± SD) vs WT for ≥ 4 experiments. **p < 0.01 by ANOVA. (Top) Culture images on differentiation d8, with HPCs (light color) floating above an adherent monolayer. Scale bar, 20 mm