Fig. 3

Hem-1^−/− hematopoietic stem and progenitor cells migrate and adhere normally. a Actin polymerization and capping are normal in E14.5 Hem-1^−/− FL LSK cells in response to SDF-1α stimulation. Representative microscopic images are shown (scale bar = 10 μm). b Migration towards SDF-1α and adherence to fibronectin were not different in E14.5 Hem-1^−/− FL Lin⁻ hematopoietic cells compared to Hem-1^+/+ FL Lin⁻ cells, but they could be suppressed by inhibition of CDC42 with CASIN, a specific CDC42 inhibitor (n = 3, ***p < 0.001, ****p < 0.001, two-way ANOVA). c Homing of CFSE-labeled E14.5 Hem-1^−/− FL LSK hematopoietic cells to radiation-ablated adult marrow as measured by flow cytometry was not different from littermate E14.5 Hem-1^+/+ FL LSK cells at 16 h after injection. However, there were decreased CSFE-labeled E14.5 Hem-1^−/− FL LSK cells present in the marrow at 48 h after injection (n = 5, **p < 0.01, Student’s t test). d Homing of DiD-labeled E14.5 Hem-1^−/− FL LSK cells to the osteoblastic niche of col2-3-EGFO reporter mice was normal compared to littermate Hem-1^+/+ equivalent cells. However, after 48 h, there were decreased CSFE-labeled E14.5 Hem-1^−/− FL LSK cells present in the osteoblastic niche (n = 266–418 cells in three distinct mice, scale bar = 50 μm, ***p < 0.001, Student’s t test). e There were fewer E14.5 Hem-1^−/− FL Lin⁻ hematopoietic cells cycling as measured by BrDU incorporation and more undergoing apoptosis as measured by Annexin V expression after transplantation and migration to a radiation-ablated adult marrow than comparable littermate Hem-1^+/+ cells (n = 5, **p < 0.01, Student’s t test)