`Trials must be monitored'
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Though using the patient's own stem cells to treat heart failure has been shown not to damage the heart, the mechanism by which stem cells improve the heart's condition is not well understood.
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"It's fine if the patients treated at AIIMS are part of a research protocol" John Martin
Stem cell therapy: Clinical trials have to be done on humans at some point of time. But we need to have good background knowledge before venturing into this, says Azim Surani, Director of Cambridge Stem Cell Institute, U.K. — Photo: K. Gopinathan
ONE OF the major objections to embryonic stem cell research is due to the possibility of exploiting women for eggs. Unlike using extra embryos found in infertility clinics for stem cell research, producing embryos to harvest stem cells can happen only when eggs are available.
With a poor track record to reach the blastocyst stage, the number of eggs that get wasted is high using the somatic nuclear transfer technique.
South Korean scientists, for instance, needed more than 250 eggs before one reached the blastocyst stage. The problem of egg scarcity can be wished away if eggs could be produced artificially. "Producing synthetic oocytes is the answer," said Azim Surani, Director, Cambridge Stem Cell Institute, U.K. "But they are in the very stages of development." Dr. Surani was in Bangalore recently to participate in the Indo-U.K. stem cell workshop.
Scientists have been able to derive germ cells from embryonic stem cells and under some culture conditions have been able to produce eggs and sperms from these germ cells.
Advantages aplenty
"Much work has to be done before we are able to produce good synthetic ooyctes," he explained. The advantages of producing synthetic oocytes are aplenty.
"If we can make an unlimited supply of oocytes synthetically, then we can take adult somatic cells and make embryonic stem cells," he added. "In turn we can produce a large repertory of embryonic stem cells." Deriving primordial germ cells has been studied in mice and the principle has been established. "So there is an incentive to do it in humans too," he commented.
Doing away with human eggs to produce embryos is one of the advantages. With the starting material being synthetic, many of the ethical issues surrounding embryonic stem cell research will be addressed. "Producing embryos to harvest stem cells may become less problematic (ethically)," he remarked.
But the issue that currently seems to cloud stem cell research in India is the eagerness of scientists and doctors to actually jump the gun and use stem cells for therapeutic purposes and project it as a simple and efficient way to treat and at times cure many diseases.
"It is very important that all clinical applications are monitored by a local ethical committee and broad guidelines are drawn for use of stem cells in patients," he cautioned. "In a sense it is an experimentation on humans."
Human trials should be done under the best conditions. "The danger is if it is not done the right way and if something goes wrong then people will lose faith and there could be a backlash," he cautioned.
"It has to be done on humans at some point of time. But we need to have good background knowledge before venturing into this. And if adopted prematurely it will damage all work done on stem cells."
Dr. John Martin, Professor of Cardiovascular Medicine at the University College London shares Dr. Surani's views. "Scientific integrity determines the way science is applied into clinical practice," he remarked.
According to him, removing stem cells from the same person before injecting them into the artery to treat the patients (autologous) with heart failure is still at an experimental stage.
"It is fine if the patients treated at AIIMS are part of a research protocol," he stressed. "Research and treatment are different."
According to him, the need to show restraint is clear. "A double blind, randomised control trial is essential. Till date such a study has not been undertaken anywhere in the world," he pointed out.
A few studies that have used autologous stem cells to treat heart failure have shown no serious change to rhythm or damage to heart.
But the mechanism by which the stem cells improve the heart's condition is still not clearly understood. "Placebos by themselves have a great effect to improve the heart condition," Dr. Martin warned. `So a right selection of control group is essential."
"Getting your work published in a peer-reviewed journal is very important," he added. "It has helped me understand some mistakes." Incidentally, Dr. P. Venugopal, Director of AIIMS preferred to let the world know about his success not through a peer-reviewed journal but a newspaper. And the ramifications are aplenty.
Less expensive option
The urge to use adult stem cells to treat heart disease is seen as a less expensive and guaranteed option by many doctors in India and many have jumped on to the bandwagon.
The PTI reported that the ICMR is flooded with applications from doctors who want to use stem cells. It is not restricted to treating heart failures alone.
So are the doctors using the patients as guinea pigs? And what if even a few incidents prove to be disastrous? "The public will lose confidence and all scientists will stand to suffer," Dr. Surani warned.
Incidentally, stem cell research is highly regulated in the U.K. Licences are required even to make cell lines let alone do research with stem cells or use it for therapeutic purposes. Till date the Human Fertilisation and Embryology Authority (HFEA) has given two licences to clone for therapeutic purposes. "It is not free for all (in the U.K.), but the Authority (HFEA) does not stop anybody," he said. "If it has merit then permission is granted. It is just that a case has to be made."
"If you don't have such regulations and strict enforcement then rogue scientists can do anything," Dr. Surani commented. Only time will tell whether the AIIMS adventure will open a Pandora's box.
R. Prasad
in Chennai
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