CXCR-4 expression is up-regulated in sorted CD34+ cells undergoing apoptosis
| Source of cells . | Apoptosis-inducing incubation time, h . | CXCR-4 expression (mean ± SD) . | |
|---|---|---|---|
| % of positive cells . | MFI (AU) . | ||
| Inc−CD34+CD38− | 0 | 6.1 ± 2.3 | 20 ± 8.5 |
| 48 | 24.2 ± 6.1* | 27 ± 9.8 | |
| Inc−CD34+CD38+ | 0 | 18.3 ± 6.8 | 38 ± 12.5 |
| 48 | 44.2 ± 9.9* | 77.2 ± 18.8 | |
| Inc−CD34+[G0] | 0 | 8.8 ± 3.4 | 12.5 ± 8.6 |
| 48 | 31.5 ± 8.2* | 28.6 ± 9.6 | |
| Inc−CD34+[G1 + S + G2/M] | 0 | 19.8 ± 2.6 | 32.6 ± 9.1 |
| 48 | 54.8 ± 11* | 65.3 ± 12.5 | |
| Source of cells . | Apoptosis-inducing incubation time, h . | CXCR-4 expression (mean ± SD) . | |
|---|---|---|---|
| % of positive cells . | MFI (AU) . | ||
| Inc−CD34+CD38− | 0 | 6.1 ± 2.3 | 20 ± 8.5 |
| 48 | 24.2 ± 6.1* | 27 ± 9.8 | |
| Inc−CD34+CD38+ | 0 | 18.3 ± 6.8 | 38 ± 12.5 |
| 48 | 44.2 ± 9.9* | 77.2 ± 18.8 | |
| Inc−CD34+[G0] | 0 | 8.8 ± 3.4 | 12.5 ± 8.6 |
| 48 | 31.5 ± 8.2* | 28.6 ± 9.6 | |
| Inc−CD34+[G1 + S + G2/M] | 0 | 19.8 ± 2.6 | 32.6 ± 9.1 |
| 48 | 54.8 ± 11* | 65.3 ± 12.5 | |
PB CD34+ cells were purified immediately after density gradient separation (Inc−) and were sorted according to CD38 antigen expression or to their cell cycle status based on Hoechst and pyronin Y staining. Cells (1 × 105/mL) were incubated under apoptosis-inducing culture conditions (serum- and cytokine-free medium [IMDM]) for 48 hours prior to the harvesting for CD34 and CXCR-4 labeling and flow cytometer analysis. Cell debris was excluded from the analysis by gating on apoptotic and live cells on forward light scatter versus side light scatter dot plots. Percentage of CD34+CD38−, CD34+CD38+, CD34+[G0] and CD34+[G1 + S + G2/M] cells coexpressing CXCR-4 was calculated after gating on CD34+ cells.
Results are based on 3 independent experiments.
P < .05 versus 0 hours incubation.