Scientists Make Artificial Protein Mimic Blood

Al writes "Researchers at the University of Pennsylvania have created a protein that can carry and deliver oxygen — a useful step towards developing artificial blood. This would avoid the problems involved with donor blood — contamination, limited storage, and short supply — and lead to easier and faster blood transfusions on the battlefield and in trauma cases. The Penn researchers used three amino acids to make a four-helix columned protein structure put a smaller structure, called a heme, inside it. The heme is a large flat molecule that has an iron atom at its center, which oxygen binds to. The researchers also made the protein structure flexible, so that it can open to receive the oxygen and close again without letting any water in. They did this by linking together the helical columns with loops to restrict their motions, giving the final structure a candelabra shape."

Re:Finally

[fuzzyfuzzyfungus]

Or, y'know, a bunch of powerful immortal creatures of darkness no longer have any need to keep us around...

Incidentally this [wikipedia.org] is fun viewing in that vein.

Various Questions

[D Ninja]

This sounds extremely cool, and very useful.

Some questions I would have is:

1. How much of this 'blood' can a human take before his/her body rejects it (if it ever does)?

2. How quick and expensive is it to create, say, a liter of blood?

3. Is there any reason that this blood wouldn't be able to combine with certain blood-types?

Either way, this is some great research that UPenn is doing. I'm excited to see where this goes.

Re:Various Questions

[Vectronic]

4. Does this break down into any sort of toxin?
5. Can kidneys, livers and pancreases deal with this?
6. How do common diseases or viruses interact with it.

Personally, I think those would rank #1, 2 and 3... but to each their own.

further obstacles

[Anonymous Coward]

A great milestone, but a paragraph near then end of the article outlines the obstacles still to be crossed:

To use the artificial protein in the human body, the researchers will need to make sure that it can hold on to the oxygen long enough to be useful, work in a cellular environment, and be nontoxic. The protein also must not be identified by the immune system as a contaminant to be flushed out through the kidneys, adds James Collman, a professor of chemistry at Stanford University, who makes synthetic hemes that bind to oxygen.

I would modify one sentence though: "hold on to the oxygen long enough to be useful and no longer"
What makes carbon monoxide so dangerous is that hemoglobin has more affinity for it than for oxygen. Once CO binds with it it is basically out of commission until the blood cell is reclaimed by the body. If this protein-heme compound has a higher affinity for O2 than hemoglobin, it could "suck" the O2 out of the remaining blood the person has, reducing the effectiveness of the circulatory system as a whole

Re:Various Questions

[Cillian]

Well, I'd preface this by pointing out that they aren't yet creating blood, just a single component that mimics a single property of real blood. Proper blood does a whole lot more than just carry oxygen. To copy real blood, the full mixture would need the correct solubility of CO2, some sort of clotting system, and a whole lot more (This is just from GCSE biology, I'm hardly an expert). Although, it could certainly be helpful even if it doesn't do all that - presumably a bunch of crap blood substitute is still better than no blood at all!