Cloning Frequencies of B-Lineage Precursor Populations
| Sorted Population* . | Wells Plated . | Clones Assessed for Lineage Potential . | Cloning Frequency (% of clones with phenotype) . | ||||
|---|---|---|---|---|---|---|---|
| Total . | Total B Lineage . | B Only . | B + M Bi-potential . | M Only . | |||
| Lin− c-kitHi | 560 | 92 | 1/4.7 | 1/100 | 1/166 | 1/250 | 1/5.8 |
| (3.3%) | (2.2%) | (94.5%) | |||||
| Lin− c-kitLo | 560 | 158 | 1/3.5 | 1/17 | 1/35 | 1/33 | 1/4.5 |
| (10.1%) | (10.8%) | (79.1%) | |||||
| Lin− c-kit− | 554 | 131 | 1/3.1 | 1/34 | 1/41 | 1/210 | 1/3.4 |
| (7.6%) | (1.5%) | (90.9%) | |||||
| Sorted Population* . | Wells Plated . | Clones Assessed for Lineage Potential . | Cloning Frequency (% of clones with phenotype) . | ||||
|---|---|---|---|---|---|---|---|
| Total . | Total B Lineage . | B Only . | B + M Bi-potential . | M Only . | |||
| Lin− c-kitHi | 560 | 92 | 1/4.7 | 1/100 | 1/166 | 1/250 | 1/5.8 |
| (3.3%) | (2.2%) | (94.5%) | |||||
| Lin− c-kitLo | 560 | 158 | 1/3.5 | 1/17 | 1/35 | 1/33 | 1/4.5 |
| (10.1%) | (10.8%) | (79.1%) | |||||
| Lin− c-kit− | 554 | 131 | 1/3.1 | 1/34 | 1/41 | 1/210 | 1/3.4 |
| (7.6%) | (1.5%) | (90.9%) | |||||
Single Lin− c-kitHi, Lin−c-kitLo, and Lin− c-kit− cells were sorted directly onto S17 stromal cells along with IL-7. Randomly selected clones were harvested after 10 to 13 days and assessed by flow cytometry. Clones were assessed for CD45R, CD19, and Mac-1 (CD11b). Clones contained only CD45R+ CD19+ B-lineage cells, Mac-1+ cells, or cells of both types. Total cloning frequencies reflect wells with growth relative to total wells plated. These numbers were multiplied by flow cytometry results for the analyzed clones to yield cloning frequencies for each type of progenitor. Results were combined from two independent experiments using marrow pooled from three mice.