The great divide of immortal cells
Wouldn't you like to live forever? This is just one of the questions being raised by scientists following the success of a recent experiment which produced cells that could divide an infinite number of times.
Normal human cells can only divide a certain number of times before they stop, explained Michael Ouellette, a research fellow at the Northwestern Medical Centre at the University of Texas in Dallas where this study was conducted.
They found cell division is controlled by telomeres, the ends of a chromosome, he said. Telomeres cap the chromosome but they eventually deteriorate to a point where cell division can no longer occur.
Ouellette explained the research team in Texas discovered the enzyme telomerase could build the telomere sequence from scratch. Telomerase is generally only found in gamete cells such as an egg or sperm, he added.
"By forcing the expression of telomerase into somatic cells, those cells might become immortal," he said. These cells have the characteristic of young cells and divide as young cells, Ouellette noted.
"I think it is a very exciting study because it offers control of cellular senescence without changing the [genetic make-up]," said David Litchfield, a biochemist at Western. Senescence is the term used to describe cell mortality.
There are still a lot of questions to answer but this study has a lot of potential, he added.
The same ethical questions apply to this research as would apply to any procedure which might prolong life such as the transplanting of organs, said Michael Prieur, a theology professor at King's College.
"The bigger questions are centered around a social cultural aspect, this business of living to 120 or 130 assumes everything else is working fine," he said.
This study may have a lot of potential but Ouellette stopped short of calling this discovery the 'fountain of youth.' There are many different processes present in aging such as structural damage, that occur with time, he said.
"We might be able to cure some of the systems which fail with age by rejuvenating cells taken from a person and then putting them back," Ouellette explained.
He added this research may eventually be used to fight cancer and to repair the immune systems of people who have been infected with the AIDS virus.