STAT1 is the upstream regulator of LIN28A in imMKCLs. The siRNA SMARTpool designed against human STAT1 (siSTAT1) and a siNT were transfected into imMKCLs. (A) A schematic illustration of the experimental procedure of siRNA-mediated STAT1 knockdown in imMKCLs. (B) STAT1 knockdown significantly decreased STAT1 and LIN28A mRNA expression and increased let-7a-5p expression. (C) Intracellular protein levels of STAT1 (mean fluorescence intensity detected in siNT or siSTAT1 imMKCLs by intracellular flow cytometry. STAT1 expression was compared using a histogram overlay in the left panel. (D) STAT1 knockdown improved iPSC-PLT generation by imMKCLs (clone 7). (E) Representative flow cytometry plots of iPSC-PLTs generated from siNT or siSTAT1 imMKCLs in static or turbulent flow conditions. CD41⁺CD42b⁺ platelets were identified from a platelet-sized gate. (F) STAT1 knockdown decreased mRNA expression of representative immune-related genes in imMKCLs. (G) The secretion of IL-8 from clone 7 and clone 7-3 during the maturation stage (DOX-OFF day 6). Data are expressed as the mean ± SEM from 3 to 4 independent experiments. Unpaired 2-tailed Student t tests were used to assess statistical significance. IL-8, interleukin 8; MK, megakaryocyte; ns, not significant.