Culturing Cell Lines

As you might note from comments presented throughout this module, there are many problems with growing cells, much less trying to control their differentiation process. Most of the research has been conducted with cultured cells. Cultured cells offer many advantages including:

1. Single cell types can be grown.
2. Cells can be grown in large quantities.
3. Many different cell activities can be observed.
4. The process of cell differentiation can be observed.
5. The response of cells to various chemicals can be studied without potentially endangering an organism.

However, cell cultures are not easy to grow. Many cells require a complex medium that has been difficult to replicate. Consequently, many animal cells are grown in blood serum. Most animal cells can only divide a limited number of times, usually between 50 and 100 times, before they undergo senescence and die. Now many cell types have been genetically modified so that they can divide indefinitely.

• What do you think are the most common nutrients needed to culture animal cells?
• What do you think are the most common nutrients needed to culture plant cells?
• Why do most animal cells die after 50 to 100 cell divisions?
• What do specially developed cell lines have in common with malignant cells?
• What would you alter genetically to develop cell lines?