Kit ligand has a critical role in mouse yolk sac and aorta-gonad-mesonephros hematopoiesis (2018)
Figure 7

Figure 7. Endothelial Kitl is required for hematopoietic stem and progenitor cells in the AGM and for EMPs in the YS

A. Schematic showing the two genetically modified mouse lines crossed to perform conditional deletion of Kitl in endothelial cells.

B. Left: number of Ter119- Kit+ CD41+ CD16/32+ EMPs in Tie2Cre::Kitl∆/∆ and control Kitlf/f or f/+ E11.5 YS, determined by flow cytometry. Data are the mean (±SD) of 8 control and 7 Tie2Cre::Kitl∆/∆ YS analyzed individually over 4 independent experiments. Tail somite range: 13-16. Middle: number of pre-HSC type I (Ter119- VE-Cadherin+ Kit+ CD41+ CD45-) and pre-HSC type II/HSC (Ter119- VE-Cadherin+ Kit+ CD41+ CD45+) in Tie2Cre::Kitl∆/∆ and control Kitlf/f or f/+ E11.5 AGM+VU, determined by flow cytometry. Data are the mean (±SD) of 7 control and 5 Tie2Cre::Kitl∆/∆ AGM+VU analyzed individually over 3 independent experiments. Tail somite range: 14-15 (Kitlf/f, f/+); 14-16 (Tie2Cre::Kitl∆/∆). Right: number of Ter119- Kit+ CD41+ CD16/32+ EMPs and Ter119- Kit+ CD41- CD71+ CD44+ early erythroid cells in Tie2Cre::Kitl∆/∆ and control Kitlf/f or f/+ E11.5 FL, determined by flow cytometry. Data are the mean (±SD) of 7 control and 5 Tie2Cre::Kitl∆/∆ FL analyzed individually over 3 independent experiments. Tail somite range: 13-16.

C. CFU-C numbers in Tie2Cre::Kitl∆/∆ and control Kitlf/f or f/+ E11.5 YS. Data are the mean (±SD) of 6 control and 3 Tie2Cre::Kitl∆/∆ YS plated in duplicate in 2 independent experiments. Tail somite range: 13-16.

D. Analysis of long-term multi-lineage HSC potential in E11.5 Tie2Cre::Kitl∆/∆ and control Tie2Cre::Kitl∆/+ or Kitlf/f or f/+AGM+VU. Irradiated CD45.1 syngeneic mice were transplanted with 1 e.e. of AGM+VU cells. PB chimerism is represented as the percentage of donor CD45.2+ cells among total CD45+ cells, 16 weeks after transplant. A total of 29 recipients were transplanted with Tie2Cre::Kitl∆/+ or Kitlf/f or f/+ cells and 8 with Tie2Cre::Kitl∆/∆ cells, over 7 independent experiments. Kitlf/f or f/+ is represented with a circle, Tie2Cre::Kitl∆/+ a triangle and Tie2Cre::Kitl∆/∆ with a square. Tail somite range: 12-17 (control); 12-17 (Tie2Cre::Kitl∆/∆).

E. CFU-C numbers in Tie2Cre::Kitl∆/∆ and control Kitlf/f or f/+ E11.5 Fl. Data are the mean (±SD) of 7 control and 5 Tie2Cre::Kitl∆/∆ FL plated in duplicate in 3 independent experiments. GEMM: granulocyte, erythroid, monocyte/ macrophage, megakaryocyte; G/M/GM: granulocyte, monocyte/macrophage; Ery: erythroid. Tail somite range: 13-16.

F. Number of phenotypic LSK, HPC and HSC per FL in E12.5 Tie2Cre::Kitl∆/∆and control (Kitlf/f or f/+) FL, determined by flow cytometry and total FL cell counts. Cells were gated as 7-AAD- Lin- (F4/80- CD3e- Nk1.1- Ter119- Gr-1- B220- CD19-). LSK: Lin- Sca1+ Kit+; HPC: Lin- Sca1+ Kit+ CD48+ CD150- and HSC: Lin- Sca1+ Kit+ CD48- CD150+. Gating strategy is shown in Figure EV4E. Data are the mean (±SD) of 12 control and 6 Tie2Cre::Kitl∆/∆ FLs analyzed individually over 3 independent experiments.

G. Total cellularity of E12.5 Kitlf/f or f/+ (n=14) and Tie2Cre::Kitl∆/∆ (n=11) FL. Error bars represent SD.

Data information: *P<0.05 (Unpaired two-tailed Student t-test).