Molecular Biology of the Cell by Bruce Alberts, Alexander Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter Walter by by Bruce Alberts, Alexander Johnson, Julian Lewis, David Morg

ISOLATING CELLS AND GROWING THEM IN CULTURE
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activates a poorly understood protective mechanism (discussed in Chapter 17)
that stops cell division—a process sometimes called “culture shock.” To immortalize
these cells, one has to do more than introduce telomerase. One must also
inactivate the protective mechanisms, which can be done by introducing certain
cancer-promoting oncogenes (discussed in Chapter 20). Unlike human cells,
most rodent cells do not turn off production of telomerase and therefore their
telomeres do not shorten with each cell division. Therefore, if culture shock can
be avoided, some rodent cell types will divide indefinitely in culture. In addition,
rodent cells often undergo spontaneous genetic changes in culture that inactivate
their protective mechanisms, thereby producing immortalized cell lines.
Cell lines can often be most easily generated from cancer cells, but these cultures—referred
to as transformed cell lines—differ from those prepared from normal
cells in several ways. Transformed cell lines often grow without attaching to a
surface, for example, and they can proliferate to a much higher density in a culture
dish. Similar properties can be induced experimentally in normal cells by transforming
them with a tumor-inducing virus or chemical. The resulting transformed
cell lines can usually cause tumors if injected into a susceptible animal.
Transformed and nontransformed cell lines are extremely useful in cell
research as sources of very large numbers of cells of a uniform type, especially
since they can be stored in liquid nitrogen at –196°C for an indefinite period and
retain their viability when thawed. It is important to keep in mind, however, that
cell lines nearly always differ in important ways from their normal progenitors in
the tissues from which they were derived.
Some widely used cell lines are listed in Table 8–1. Different lines have different
advantages; for example, the PtK epithelial cell lines derived from the rat
Table 8–1 Some Commonly Used Cell Lines
Cell line*
3T3
BHK21
MDCK
HeLa
PtK1
L6
PC12
SP2
COS
Cell type and origin
Fibroblast (mouse)
Fibroblast (Syrian hamster)
Epithelial cell (dog)
Epithelial cell (human)
Epithelial cell (rat kangaroo)
Myoblast (rat)
Chromaffin cell (rat)
Plasma cell (mouse)
Kidney (monkey)
293 Kidney (human); transformed with adenovirus
CHO
DT40
R1
Ovary (Chinese hamster)
Lymphoma cell for efficient targeted recombination (chick)
Embryonic stem cell (mouse)
E14.1 Embryonic stem cell (mouse)
H1, H9 Embryonic stem cell (human)
S2
BY2
Macrophage-like cell (Drosophila)
Undifferentiated meristematic cell (tobacco)
*Many of these cell lines were derived from tumors. All of them are capable of indefinite
replication in culture and express at least some of the special characteristics of their
cells of origin.