Human blood from the lab? It's about time.
A small, struggling biotech company named Advanced Cell Technology (ACT) in Massachusetts, USA, announced this week that it had found a way to mass-produce red blood cells (RBCs) using stem cells taken from human embryos. The idea is not new, but ACT’s method is a hundred times more efficient than any other.
This is important because of the tremendous demand for human blood. Hospitals need vast quantities of it. A single road accident victim may need as many as 50 units, and other kinds of surgeries need amounts varying from a few to dozens of units. Most of us have been asked to donate blood to replenish hospital stocks when a friend or a relative was about to undergo surgery, and have rushed to hospital even in the middle of a working day.
By some figures India needs as many as 10 crore units of blood annually. A sizeable proportion is met not by voluntary donors but by professionals — those people, usually poor, who sell their blood periodically to blood banks around the country.
The risks to blood recipients are great, because even though each unit is supposed to be screened under the Drugs and Cosmetics Rules (1992 and 2001), no test is yet reliable or sensitive enough to always detect even the top three viral infections that come with donated blood — hepatitis B and C, and HIV. Many blood banks still do not have testing equipment, and professional donors, being poor, are high-risk; what’s more, they may donate more frequently than they should, under different names in different places. The only real safeguard, experts say, is honest and well-informed donors.
Infection rates in India are harrowing, although the data are very imperfect. Figures from earlier this decade indicate that perhaps 7 per cent of patients getting between one and eight units of blood also got the hepatitis virus. It’s worse for those who need regular transfusions, like thalassaemia sufferers (of whom one Lucknow study found 69 per cent with these viruses).
ACT’s lab method will not replace human blood donors for a while yet, because the technique needs to be fine-tuned and made economical enough to replace human donors. Companies working on stem cell applications are starved for funding in many countries because of official moral objections to the use of human stem cells, especially those from embryos. But this is a promising step towards solving a desperate problem.