Figure 6.

HSC activity is preserved in vivo with the addition of MRI tracer. Myeloablated murine hosts were transplanted with labeled or unlabeled syngeneic bone marrow, with untransplanted mice serving as a negative control (n = 8 per cohort). On day 12 (day 11 for untransplanted recipients), spleens were harvested and CFU-S enumerated. Results represent the average CFU-S per animal. Significantly fewer numbers of colonies were measured in untransplanted recipients compared to labeled or unlabeled transplanted recipients (p < 0.0001 for each comparison). No significant differences in colony number were found between labeled and unlabeled cells when analyzed by unpaired t test (with or without Bonferroni correction).