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All Blood Converted to Type O?
UnanimousCoward writes "The BBC is reporting that scientists claim to have discovered a technique to convert all blood into Type O with the discovery of an enzyme that can strip the A and B antigens. This has implications to transform the stored blood supply into transfusable blood for all. It does not address the RH negative issue, however."
Now I can't sell my rare blood at a premium. It was my only worthwhile body fluid since they shut down the saliva banks.
You can't talk about Wikipedia's flaws on Wikipedia
The Japanese are totally gonna freak out...
Scientists have discovered enzymes that can efficiently convert blood groups A, B and AB into the 'universal' O group -- which can be given to anyone but is always in short supply.
The two novel glycosidase enzymes were identified in bacteria by an international team led by Henrik Clausen of the University of Copenhagen in Denmark. The researchers hope that the enzymes will both improve the erratic supplies of blood around the world, and also the safety of transfusions. Clinical trials to test the safety and effectiveness of their converted blood are being planned.
The ABO blood-type system is based on the presence or absence of the sugar-based antigens 'A' and 'B' on red blood cells. Type O blood cells have neither A nor B antigens, so may be safely transfused into anyone. But types A, B and AB blood do, and cause life-threatening immune reactions if they are given to patients with a different blood group. The bacterial glycosidase enzymes strip these antigens away from A, B and AB blood.
The idea of such antigen-stripping goes back to the early 1980s, with the discovery of an enzyme in coffee beans that removes B antigens from red blood cells1. Early-stage clinical trials showed that the converted blood could be safely transfused into individuals of different blood groups; no traces of enzyme or antigen remained to cause reactions2. But the enzyme reaction was far too inefficient to make large-scale conversion practical.
Clausen's team screened 2,500 extracts from different bacteria and fungi for their ability to cleave off A and B antigens. The newly discovered bacterial 'B' enzyme is nearly 1,000 times more efficient then the coffee-bean B enzyme -- the additional discovery of an enzyme to remove A antigens means that all blood types can now be converted. The work is reported in Nature Biotechnology3.
(snip)
Diesel.
Not entirely, there is such a thing as graft Vs host, whereby if the recipient receives too much blood the donor blood can attack the person's body. Yes you can strip the white cells, but this is slow and costly, the former prohibits doing it at time of need, the latter from doing it "just in case". Not normally an issue except when massive bleeding due to extreme trauma or bleeding disorder are present as below.
As the father of a type O son with hemophilia this is awesome news. Opens up a much wider source of blood should the worst happen, especially since my wife and I are neither type O, and my father in law, while type O is also hemophilic.
-nB
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blood is a horribly complex substance.
In labs, there are several growth mediums made from cow blood (remove the red blood cells as well as several other factors). They can't be properly synthesized because of how complex it is, and that's even after the most complex stuff is removed.
It's not suprising at all that we can't synthesize it, but it's nice that we can "produce" type O from other types.
34486853790
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Something I didn't know before that I learned from the article: Anyone can receive type O blood without risk
I got that from junior high biology. Actual issues are more complicated when you get in deep, of course. One oddball is that you can usually survive 1 non-matching transfusion, even if it's incompatible. After that your immune system is 'primed', much like for a vaccination, and will attack a second transfusion with extreme prejudice, likely resulting in your death.
And we are testing at least one blood substitute. The last one I read about(sorry, dead tree article), was intended for use in ambulances, which can't normally carry blood. Unfortuantly, it actually performed worse than saline IV's when it came to patient survival.
As for simply cloning a blood supply, it's difficult because you'd have to clone marrow, as blood cells no longer have a nucleous. Not insurmountable at this point, but currently unable to compete with donated blood.
I don't read AC A human right
Although ABO and RhD grouping systems are the most well-known and the most important, there are a myriad of other blood groups (about 29 last time I checked) that are of relevance when it comes to crossmatching blood for a patient.
Whilst this potentially is a great step forward, as always with biomedical headlines, it's not the be-all and end-all.
Not a member of the General Public
Bad news for Vampires, Type A is the tastiest. So much for just going to the blood bank for meals!
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Naturally, before this sees widespread clinical use, it'll have to go through a very stringent set of studies, tests, trials, and approvals. So, it may well be 5-10 years before this sees even pilot-program use. Even once in place, this process won't lessen the demand for blood of all types, merely make the blood supply more available.
So, in the meantime, everyone who is able should at least consider donating blood. It is fast, easy, and (nearly) painless. Many may object to the exclusion criteria used by the Red Cross and other organizations, but the overwhelming majority of eligible donors simply do not give. Chances are good that, at some point in your life, you too will need a blood transfusion.
Find a blood drive near you.
Is half a problem not a problem?
you can usually survive 1 non-matching transfusion, even if it's incompatible. After that your immune system is 'primed', much like for a vaccination, and will attack a second transfusion with extreme prejudice, likely resulting in your death.
Which brings up the issue of whether the body would develop an immunity to the enzyme, potentially producing a fatal anaphylactic reaction upon a future transfusion.
On the other hand, if the enzyme remains in the serum rather than attaching to the red cells the reaction would not produce the fatal clumping. Meanwhile the allergy to the enzyme, even if severe, could be handled by other drugs...
Which would also suppress the immune system somewhat - in a hospital "superbug" environment. So artificial type-O will likely remain an emergency measure, and type-O donors will remain in demand.
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My day job is to run a blood bank.
The enzymes discussed in the article are the next step in 25+ years working toward the goal of making blood universally compatible. The enzymes are years and years away from routine use, if they ever do make it to market. Offhand, major questions that need to be addressed include: Does it *really* work? Is the process cost-effective at manufacturing scales? Is it safe? Does the enzyme affect other proteins so people make antibodies?
Conversion of non-O RBCs to group O RBCs will make them more widely compatible, and may alleviate the shortage of group O RBCs, but does not affect Rh compatibility or the compatibility of platelets or of FFP. We would still have shortages of these products even when the process is up and running, and, so, we still need people to donate.
There are a number of guesses, comments, and half-truths posted above. I'll do my best to answer specific (on-topic!) questions posted as replies to this comment.
Teidou.