Cells to be transferred were FACS sorted, washed with endotoxin-free PBS and resuspended at the desired concentration in endotoxin-free PBS, not more than 10k cells/mL. Neonatal (d0 to d3 after birth) Csf2ra−/− recipient mice were anesthetized by isoflurane inhalation and subsequently injected intranasally with 10 mL of cell suspension (not more than 100k cells/mouse). Mice were then let age and used for experiment when they reached an age of 8-10 weeks.
The number of cells to be transferred was optimized to their engraftment ability: AM and FeMo were better than BMo in engraftment and therefore as little as 50k cells was enough to generate normal number of AM in adult mice; for BMo 100k cells were necessary to obtain comparable cell number in adult mice.