Fig. 1

Femur bone marrow responses at acute and chronic stages following TBI. (A-E) Flow cytometry was performed in whole blood and femur bone marrow at 1, 3, and 7d post-injury. TBI increased the percentage of myeloid cells (% CD11b + of CD45 + cells) in blood (A) and bone marrow (B). Percentages of lineage-c-Kit + Sca1+ (LSK+) stem/progenitor cells were elevated in bone marrow after TBI (C). A representative dot plot of LSK + populations at 3d TBI is indicated in the left panel of C. Quantification of LSK + cells is shown in the right panel of C. The mean fluorescence intensity (MFI) of cell cycle markers Ki-67 (D) and PCNA (E) were seen significantly increased in the LSK + population at 1d post-injury. n = 6–10 mice/group. (F-H) The proliferative status of LSK + cells was assessed at 120 days post-injury (dpi). n = 4 (Sham) and 6 (TBI) mice/group. (I-J) Chronic TBI at 365 dpi caused a significant reduction in circulating (I) and bone marrow (J)-derived white blood (CD45+) cells. n = 6–11(blood) and 4–6 (bone marrow) mice/group. For all histograms, light gray = fluorescence minus one (FMO) control. Data were analyzed using one-way ANOVA group analysis with Tukey’s test for multiple comparisons (A-C) or Mann-Whitney for two group comparisons (D-J). **p < 0.01, *p < 0.05