Comparison of the Frequency and Absolute Numbers of LTC-ICs, Day-12 CFU-S, and CRUs in W41/W41 and +/+ FL From 14.5-dpc Embryos
| Genotype . | Population Assessed . | Total No. (×105) . | LTC-ICs . | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| . | . | . | per 105 Cells . | per FL . | CFU-S . | CRUs . | ||||
| . | . | . | BM Feeder . | S17 . | BM Feeder . | S17 . | per 105 Cells . | per FL . | Frequency . | per FL . |
| C57BL/6 | Unseparated | 190 ± 20 | ND | ND | — | — | 10 ± 3 | 2,300 ± 700 | 1/1.7 × 104 (60) | 1,100 (700-1,600) |
| W41/W41 | Unseparated | 85 ± 12 | ND | ND | — | — | 9 ± 3 | 950 ± 200 | 1/1.2 × 104 (24) | 700 (500-1,000) |
| C57BL/6 | Sca-1+Lin− | 0.23 | 1/58 | 1/27 | 450 | 900 | ND | — | 1/39 (57) | 650 (450-1,000) |
| (300-650) | (700-1,200) | |||||||||
| W41/W41 | Sca-1+Lin− | 0.25 | 1/84 | 1/50 | 300 | 450 | ND | — | 1/88 (55) | 260 (200-350) |
| (200-400) | (350-600) | |||||||||
| Genotype . | Population Assessed . | Total No. (×105) . | LTC-ICs . | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| . | . | . | per 105 Cells . | per FL . | CFU-S . | CRUs . | ||||
| . | . | . | BM Feeder . | S17 . | BM Feeder . | S17 . | per 105 Cells . | per FL . | Frequency . | per FL . |
| C57BL/6 | Unseparated | 190 ± 20 | ND | ND | — | — | 10 ± 3 | 2,300 ± 700 | 1/1.7 × 104 (60) | 1,100 (700-1,600) |
| W41/W41 | Unseparated | 85 ± 12 | ND | ND | — | — | 9 ± 3 | 950 ± 200 | 1/1.2 × 104 (24) | 700 (500-1,000) |
| C57BL/6 | Sca-1+Lin− | 0.23 | 1/58 | 1/27 | 450 | 900 | ND | — | 1/39 (57) | 650 (450-1,000) |
| (300-650) | (700-1,200) | |||||||||
| W41/W41 | Sca-1+Lin− | 0.25 | 1/84 | 1/50 | 300 | 450 | ND | — | 1/88 (55) | 260 (200-350) |
| (200-400) | (350-600) | |||||||||
The values shown represent the mean ± SEM for total cells, Sca-1+Lin− cells, LTC-ICs, and day-12 CFU-S values and the range defined by ±SEM for CRU values derived from assessment of recipients at 16 to 20 weeks posttransplant. Similar CRU frequencies were obtained from repopulation data obtained at 5 to 8 weeks posttransplant (data not shown). Results for CFU-S were pooled from two experiments in which a total of ≥10 mice were used as CFU-S recipients. Results for W41/W41 CRUs and LTC-ICs were obtained in the same three experiments in which the total number of mice used as recipients in the CRU assays is shown in parentheses beside the calculated frequency values. Values for CRUs in +/+ FL are based on data published previously36 (n = 3) and on additional data (n = 2) generated during the course of the present experiments. Values for LTC-ICs in +/+ FL were pooled from a total of four experiments, in two of which CRU measurements were also performed.
Abbreviation: ND, not done.