NoBlood

http://news.bbc.co.uk/1/hi/health/4162016.stm

August 18, 2005

Fake blood hope for transfusions

By Marnie Chesterton
From the BBC's Material World programme

"Fake blood" molecules could revolutionise transfusions, doctors behind the research claim.

Blood transfusion is a routine clinical procedure and has saved countless lives.

But doctors are looking for artificial substitutes for real blood because of fears over contamination of supplies.

Dr Ken Lowe, of the Euro Blood Substitutes Project told BBC Radio 4's Material World all aspects of fake blood development would be examined.

The current system of blood transfusions is wasteful. A tenth of blood donations in the UK never reach the patients. It is also expensive, with each unit of blood costing over £120 to extract, screen and store.

Before testing was introduced, many thousands of people were infected with HIV via blood transfusions from infected donors.

The Aids epidemic has shaken the transfusion service and artificial blood can guarantee a sterile product.

Dr Lowe said: "There will be a revolution in those countries where the natural blood supply is heavily contaminated."

Modifying blood

A blood product extracted from cow's blood has already been approved for use in South Africa.

Artificial blood can also overcome some other problems attached to traditional transfusion techniques.

Donated blood has a relatively short shelf-life of 35 days, after which it must be thrown away. It also needs refrigeration, whereas the new product will be storable for a year and be stable at room temperature.

Professor Chris Cooper from Essex University's biochemistry department, who is also involved with the Euroblood project, said: "What we are looking for is the powdered milk equivalent for blood.

"The blood could be stored in a packet and rehydrated when required."

Blood contains the protein haemoglobin, which gives it its characteristic red colour.

Many of the haemoglobin molecules are bound within red blood cells, and it is these proteins that transport oxygen and carbon dioxide to and from tissues in our bodies.

Dr Lowe says: "The term 'artificial blood' is a bit of a misnomer.

"We're aiming to produce a replacement oxygen carrier, rather than a complete blood substitute because blood is a complex soup of materials that have many other roles besides carrying oxygen to the tissues."

The blood substitute will be injected directly into the patient, dispensing with the need to create complex artificial blood cells to enclose the artificial haemoglobin.

Producing blood substitutes

Artificial blood research falls into two camps. Research teams in the US are developing synthetic substitutes, known as fluorocarbons.

These chemicals are closely related to Teflon - the non-stick coating of frying pans and can dissolve large amounts of oxygen.

The synthetic stand-ins have already been approved for use in surgery in certain countries, but are problematic to store.

The Euro Blood Substitutes Group prefer the alternative route; mimicking nature's method of transporting oxygen.

According to Dr Lowe, some of the haemoglobin-like proteins that have been developed are even better than blood itself.

The hurdle is to develop useable quantities of modified haemoglobin.

Dr Lowe said: "The novelty of our approach is to use micro-organisms, such as yeast, as living cell factories."

The group hope to harvest viable amounts of this fake blood, exploiting techniques used in insulin production for diabetics.

Professor Cooper added: "I'm absolutely convinced that in the next ten years, there will be a significant number of artificial blood substitutes on the market that are used instead of blood in some, or perhaps all, circumstances." Material World can be heard on BBC Radio 4 at 16.30BST on Thursday 18 August.