Which statement describes immortalized cells?

Which statement describes immortalized cells?

• A. They divide forever
• B. They cannot divide
• C. They require primary cells
• D. They are identical to primary cells

Answer: (A)

Immortalized cells are defined by their ability to divide indefinitely. In normal cells, division eventually stops due to cellular aging (senescence) and telomere shortening. Immortalization involves mechanisms that bypass these limits—often by reactivating telomerase or disabling key tumor suppressor pathways like p53 and Rb—so the cells can keep proliferating beyond the usual number of generations. That’s why they are described as able to divide forever. In dental materials biocompatibility testing, immortalized cell lines provide a consistent, long-term model for screening, which helps reduce variability between experiments. However, they may not behave exactly like primary cells, which have finite lifespans and can differ in gene expression and differentiation. This is why researchers often use both immortalized lines and primary cells to get a more complete picture of a material’s biocompatibility. Other statements don’t fit as well: immortalized cells can divide, so they’re not accurate to say they cannot divide; they aren’t required to come from primary tissue, since they are established as continuous lines; and they aren’t necessarily identical to primary cells, as immortalization can alter some cellular properties.

Immortalized cells are defined by their ability to divide indefinitely. In normal cells, division eventually stops due to cellular aging (senescence) and telomere shortening. Immortalization involves mechanisms that bypass these limits—often by reactivating telomerase or disabling key tumor suppressor pathways like p53 and Rb—so the cells can keep proliferating beyond the usual number of generations. That’s why they are described as able to divide forever.

In dental materials biocompatibility testing, immortalized cell lines provide a consistent, long-term model for screening, which helps reduce variability between experiments. However, they may not behave exactly like primary cells, which have finite lifespans and can differ in gene expression and differentiation. This is why researchers often use both immortalized lines and primary cells to get a more complete picture of a material’s biocompatibility.

Other statements don’t fit as well: immortalized cells can divide, so they’re not accurate to say they cannot divide; they aren’t required to come from primary tissue, since they are established as continuous lines; and they aren’t necessarily identical to primary cells, as immortalization can alter some cellular properties.