Elements
of
Selection
in
the
Evolution
of
Cell
Lines -
Stage |
Primary explant |
Enzymatic disaggregation |
|
1. Isolation |
Mechanical damage
|
Enzymatic damage | |
| 2. Primary culture | Outgrowth (migration) |
Attachment and spreading |
|
3. Subculture |
Trypsin sensitivity Nutrient, hormone substrate limitations |
||
4. Propagation as a cell line |
Relative growth rates of different cells; Effect of cell density on predominance of normal or transformed phenotype; Nutrient, hormone and substrate limitations |
||
5. Senescence, transformation |
Normal cells die out; transformed cells overgrow |