Figure 8.

Influence of IL-3 on the endothelial to hematopoietic transition of hemato-endothelial progenitors. (A) Frequency of total CD34+ within hemanoids at different days cultured either without (w/o) cytokines, w/o cytokines+IL-3 blocking antibody (IL-3 block) or in the presence of IL-3 (n=4-7, mean±standard error of the mean [SEM]). (B and C) Analysis of CD144+/CD45- hemato-endothelial progenitors (HEP) and CD144–/CD45+ hematopoietic progenitors (HP) among total CD34+ cells within the hemanoids. (B) Representative flow cytometry data for hemanoid day (d) 8 and (C) quantification of n=4-7 over 16 days of hematopoietic specification, mean±SEM, percentage of gated population is indicated). (D) Colony forming units (CFU) in methyl-cellulose after endothelial to hematopoietic transition (EHT) culture on OP9 stromal cells in the presence or absence of IL-3 (n=4, two technical and two biological replicates, mean±SEM). (E) Schematic representation of the hemanoid model system as well as the effect of IL-3 on the hematopoietic specification of hemogenic endothelium (scheme was prepared with BioRender software). *P<0.05, **P<0.01, ***P<0.001, ****P<0.0001, ns: not significant; statistical significance was assessed using two-way ANOVA with Tukey’s multiple comparison test.