Spheres | Proliferation | Differentiation (spheres/total spheres) | |||||
---|---|---|---|---|---|---|---|
Sphere Io(n) | Renewing | NAO | NA | A | AO | O | |
E + IGF-I | 70 ± 19 | (29 /33) | 62 /97 | 26 /97 | 6 /97 | 5 /97 | 1 /97 |
64% | 27% | 6% | 5% | 1% | |||
E + IGF-I 24 hr | 46 ± 9.4 | (29 /33) | 61 /96 | 25 /96 | 4 /96 | 5 /96 | 1 /96 |
62% | 26% | 4% | 5% | 1% | |||
F + IGF | 56 ± 6.3 | (69 /77) | 68 /89 | 20 /89 | 1 /89 | ||
76% | 23% | 1% |
Single spheres were dissociated, and the cells were plated in 96-well plates in medium containing the growth factor used for the generation of primary spheres. Eight to 10 DIV later, newly generated spheres were counted (Sphere Io, mean ± SEM). Sphere renewing indicates the number of spheres able to generate new spheres in comparison to the total sphere number tested (n = 4 experiments). Spheres generated in the presence of IGF-I and either EGF (n = 7) or FGF-2 (n = 3) were induced individually to differentiate. IGF-I 24 hr indicates sphere generated with EGF and short-term exposure of IGF-I (n = 6). Cells immunopositive for the neuronal marker β-tubulin (N), the astrocyte marker GFAP (A), and the oligodendroglial marker O4 (O) were recorded for each sphere. The cell identities in spheres are represented by the abbreviations N, A, and O. The percentage of a specific sphere type in comparison to the whole population analyzed is indicated in each column. Sphere Io , primary source.