Effects of IL-3 on Lymphohematopoietic Progenitors
| Mice . | Cytokines . | Replated on Day 10 . | Replated on Day 12 . | |
|---|---|---|---|---|
| No. of 1° Colonies . | No. of Pre–B-Cell Colonies . | No. of Pre–B-Cell Colonies . | ||
| Wild-type | SF, IL-11 | 34 ± 5 | 33 ± 4 | 15 ± 2 |
| (βc +/+, βIL-3 +/+) | SF, IL-11, IL-3 | 32 ± 6 | 0 | 0 |
| βc −/− | SF, IL-11 | 36 ± 2 | 34 ± 2 | 14 ± 2 |
| SF, IL-11, IL-3 | 35 ± 2 | 0 | 0 | |
| βIL-3 −/− | SF, IL-11 | 35 ± 5 | 32 ± 2 | 16 ± 1 |
| SF, IL-11, IL-3 | 36 ± 4 | 0 | 0 | |
| Mice . | Cytokines . | Replated on Day 10 . | Replated on Day 12 . | |
|---|---|---|---|---|
| No. of 1° Colonies . | No. of Pre–B-Cell Colonies . | No. of Pre–B-Cell Colonies . | ||
| Wild-type | SF, IL-11 | 34 ± 5 | 33 ± 4 | 15 ± 2 |
| (βc +/+, βIL-3 +/+) | SF, IL-11, IL-3 | 32 ± 6 | 0 | 0 |
| βc −/− | SF, IL-11 | 36 ± 2 | 34 ± 2 | 14 ± 2 |
| SF, IL-11, IL-3 | 35 ± 2 | 0 | 0 | |
| βIL-3 −/− | SF, IL-11 | 35 ± 5 | 32 ± 2 | 16 ± 1 |
| SF, IL-11, IL-3 | 36 ± 4 | 0 | 0 | |
Four thousand Lin− cells from the marrow of 5-FU–treated mice were cultured in methylcellulose with SF and IL-11 in the presence or absence of IL-3. Ten and 12 days later, 20 primary colonies were pooled and 5% of the cells were replated in methylcellulose with SF and IL-7. The pre–B-cell colony formation was examined on day 10 of secondary culture. Similar results were obtained in an additional experiment.