TABLE 4.
Individual Beta-gal-positive Senescent Cells and Luciferase Positive Senescent Cell Containing Colonies (Scored on Day 7 and Day 14 CFU-GEMM) from Freshly Removed Bone Marrow Isolated from p16+/LUC and C57BL/6 mice 60 Days after 8 Gy TBI Compared to Nonirradiated Mice
| Mouse strain | Dose (Gy) | Percentage (%) senescent (β-gal) NA single cells |
No. of luciferase+ colonies/total no. of colonies | |
|---|---|---|---|---|
| Day 7 | Day 14 | |||
| p16+Luc | 0 | 7.3 ± 1.1 | 5/53 (9%) | 3/54 (5%) |
| 8 | 43.7 ± 2.8 (P < 0.0001) | 3/37 (8%) | 2/34 (6%) | |
| C57BL/6 | 0 | 5.5 ± 1.5 | 0/64 (0%) | 0/47 (0%) |
| 8 | 39.3 ± 2.1 (P < 0.0001) | 0/35 (0%) | 0/64 (0%) | |
Notes. Significant differences between 0 and 8 Gy are indicated in bold face. Cells were removed from marrow at 60 days or one year after 8 Gy TBI and single cells stained for β-gal, then placed into CFU-GEMM colony assay, as described in Materials and Methods. Results are for percentage positive cells out of 1,000 cells scored from at least 3 mice per group at each time point. P values compared with nonirradiated marrow of each representative genotype. For C57BL/6 mice, the numbers of β-gal-positive/total colonies per 104 cells were, for day 7 colonies for 0 Gy and 8 Gy TBI C57BL/6 mice, 1/54 and 3/35 and for day 14 colonies were 1/47 and 5/64, respectively, based on histochemical staining of removed and stained colonies for β-gal.