Figure 1.
G-CSF does not induce proliferation of dormant HSCs. (A) Experimental schematic. Mice were placed on dox for 12 to 16 weeks to turn off expression of H2BGFP. Four days before analysis, mice were serially treated with G-CSF, and then BM, PB, and spleen were harvested to assay GFP label dilution, CFU, and HSC (LSKCD48−CD150+) quantification. (B) Histogram of HSC GFP label dilution. (C) Quantification of LR-HSC in panel B. (D) Absolute number of LR-HSCs in the BM. (E) CFU analysis from PB. (F) HSC quantification in the spleen. (G) Updated experimental schematic. Mice were placed on dox for 7 weeks, treated with G-CSF, and then chased for an additional 8 weeks to allow homeostasis to reestablish and all HSCs to return to the bone marrow before analysis. (H) Histogram of HSC GFP label dilution. (I) Quantification of LR-HSC in panel H. (J) Absolute number of LR-HSCs in the BM. (K) CFU analysis from PB immediately after the final G-CSF treatment. (L) HSC quantification in spleen. Data are represented as mean ± SEM of 6 and 7 mice for control and G-CSF treatments, respectively. *P < .05, **P < .01, ***P < .001 by Welch’s t test.