Unfortunately, blood transfusions are commonly utilized in the United States. In fact, every two seconds, someone in the U.S. needs blood, resulting in ~30 million blood components being transfused in the U.S. every year. (American Red Cross, Blood Facts and Statistics, 2015) Even with 38% of Americans being eligible to donate blood, there is often a blood supply shortage, specifically when it comes to certain blood types. There are four blood types, A, B, AB, and O, which can donate to all blood types. Ideally, if one were able to have an excess of a blood type available for transfusions, type O would be the winner.
So how can the dream of type O blood being available on demand be achieved? Recently researchers have been working with a family of enzymes called 98 glycoside hydrolase, extracted from a strain of Streptococcus pneumoniae. The enzymes were created in lab over multiple enzymatic generations with small alterations occurring every generation to try and have the ability to alter blood types for transfusion, in case there is a shortage of a type in demand. By progressively selecting strains and altering aspects of certain enzymes that are the best at snipping away the blood antigens, researchers have been able to create an enzyme that’s 170 times more effective at it than its parent strain. (Science Alert, Scientists discover an enzyme that can change a person’s blood type, 5.1.2015)
The actual process of changing blood types involves removing antigens, a substance that causes the body to produce an immune response. With blood types, the antigen is simply an extra sugar molecule that is attached to the blood cell. Type A has A-acetylgalactosamine, type B has galactose residue, and type AB has a little of both. (Gazette Review, Enzyme That Can Change Blood Type Discovered, 5.4.15) Type O, the universal donor, has no antigen attachment. The enzyme under investigation actually removes the antigen, making any non-type O blood become type O.
However, it should be noted that the blood type transformation is not perfect. Researchers have noted that the development of these enzymes is very progressive, but the enzymes cannot remove 100% of antigens, meaning it is still under investigation and cannot be used in clinical settings at this time. Hopefully with continuation of enzymatic modifications, researchers will be able to lessen the worry that certain types are going to be unavailable when needed.
Interestingly, when researching for this piece, I wondered why exactly researchers have turned to enzymes for the solution to blood shortages instead of searching for more donors. While 38% of Americans are eligible for donating, less than 10% actually donate. I think the American Red Cross pointed out the benefits of donating with their statistical statement of “If you began donating blood at age 17 and donated every 56 days until you reached 76, you would have donated 48 gallons of blood, potentially helping save more than 1,000 lives!” (American Red Cross, Blood Facts and Statistics, 2015) One of the reasons many people do not donate blood is a fear of needles. Knowing this, I thought an interesting solution to get more people to donate might be what I wrote about last week, the HemoLink blood sampler that withdraws blood via vacuum suction. While the HemoLink is also in prototype, it has the potential to be a solution for more blood donations. The only alteration that would be needed to the device at this time is the collection container, which at this time only collects 0.15 cubic centimeters of blood. (Gizmodo, New Self-Administered Blood Collection Device Could Replace Needles, 4.19.15) But, I truly believe that if this device could be implemented for donating blood, the percentage donating would rise drastically.
I am very intrigued by the enzymatic developments and believe that it could help save lives when there is a shortage in blood supply. However, I also urge that we not bank on the fact that we may be able to alter blood. In my opinion, the real deal is the best deal, and if we could get more blood donations, would we need the enzyme? Maybe at times the enzyme could be live saving, but probably not as often as if donations suddenly spiked to 20 or even 30%. I hope that researchers are seeing the cool medical developments that have been publicized recently and are able to put their heads together for the health of all.