Expert: Florence M Rollwagen - 5/10/2009

Question
I am an Army medic and have an interest in artificial blood. How close are researchers to developing an artificial blood product that could be used outside a hospital setting? Can you identify what some of the hardships are in developing such a product? Thanks

Answer
Hi Ivan:  Thanks for your question.

Artificial blood

Hemoglobin based blood substitutes have been under development by the Army for decades.  There are any number of problems that must be overcome so that a stable (non refrigerated) product could be made available for battlefield casualties.

The first tries were based on lysed red blood cells.  Alas, free hemoglobin is a vasoconstrictor, driving up the blood pressure of patients to whom it was given.

Attempts to encapsulate hemoglobin were carried out with a number of agents.  In my lab, we tried liposome encapsulated hemglobin, which transported oxygen, but was rapidly filtered out by the spleen and liver.

Other attempts using free hemoglobin involved PEGolating the product, which prevented vasoconstriction.  Polynitroxylation was also tried with good results.

Other major problems with hemoglobin based support involved the source of hemoglobin.  Sources of hemoglobin could also transmit viruses or other pathogens.  Bovine hemoglobin could be a source of the prion disease, BSE, human hemoglobin a potential source of hepatitis or HIV.  

The Army also tried recombinant hemoglobin, but I believe those didn’t work either, probably due to cost, but I’m not sure.

Here’s a good review on Wikipedia:
http://en.wikipedia.org/wiki/Blood_substitutes

Hope this helps!  Write back if you have more questions.

FM Rollwagen, PhD