If this technology proves viable on large scale, medical laboratories in hospitals that manage blood banks could have larger supplies of universal blood units
Once again, the amazing human microbiome is at the heart of a new scientific breakthrough that could offer new tools for clinical laboratories and provide much needed resources to emergency departments and hospitals.
Canadian researchers at the University of British Columbia (UBC) in Vancouver have discovered a microbe in the human gut they believe is capable of converting donor blood into “universal” type-O blood.
“We have been particularly interested in enzymes that allow us to remove the A or B antigens from red blood cells. If you can remove those antigens, which are just simple sugars, then you can convert A or B to O blood,” Stephen Withers, PhD, a professor and biochemist at UBC explained in an American Chemical Society (ACS) news release.
Such a breakthrough would be game-changing not only for emergency departments that rely on much-needed supplies of universal-donor blood, but also for the medical laboratories that run most hospital blood banks.
Uncovering a method to transform type A blood into type O would greatly enlarge the current blood supply because type-O blood can be donated to patients regardless of which of the four main blood groups they belong to—O, A, B, or AB.
This is yet another addition to a growing list of discoveries involving human gut bacteria that Dark Daily has reported on in past years.
Withers presented his research at the 256th National Meeting and Exposition of the American Chemical Society 2018 annual meeting in Boston. Click here to watch a video of his presentation.
Using Metagenomics to Convert A/B Blood to Type O
UBC scientists relied on metagenomics—a technique that enables researchers to study microbial communities using DNA sequencing—to investigate enzymes that potentially could destroy all the A and B antigens from red blood cells, thereby converting type A and B blood into Type O universal blood.
“With metagenomics, you take all of the organisms from an environment and extract the sum total DNA of those organisms all mixed up together,” Withers said in the ACS news release.
Withers’ team considered sampling DNA from mosquitoes and leaches but ultimately turned to the human body, where they found successful candidate enzymes in the gut microbiota. They focused on glycosylated proteins called mucins that line the gut wall, providing sugars that serve as attachment points for gut bacteria, while also feeding them as they aid in digestion, the ACS report noted.
“By honing in on the bacteria feeding on those sugars, we isolated the enzymes the bacteria use to pluck off the sugar molecules,” Withers said in a UBC statement. “We then produced quantities of those enzymes through cloning and found that they were capable of performing a similar action on blood antigens.”
Although enzymes long have been considered a key to transforming donated blood to a common type, the gut enzymes the UBC team identified are 30 times more efficient at removing red blood cell antigens than previously studied enzymes, the ACS news release noted. Their findings demonstrate once again how the human microbiome is intertwined with many processes happening within the body, opening the possibility of future novel uses of enzymes.
Zuri Sullivan, an immunologist and PhD candidate at Yale University, believes the blood-converting enzymes discovered by the USB team may be the first of many discoveries revealed as researchers investigate the untapped potential of the gut microbiome to solve medical challenges.
“The premise here is really powerful. There’s an untapped genetic resource in the [genes] encoded by the gut microbiome,” she told Smithsonian Magazine.
Researchers Have High Hopes but More Testing Is Needed
According to the UBC statement, Withers and UBC colleagues microbiologist Steven Hallam, PhD, and pathologist Jay Kizhakkedathu, PhD, of the UBC Center for Blood Research, are applying for a patent on the new enzymes, while working to validate the enzymes and test them on a larger scale in preparation for clinical testing.
In addition, the ACS news release notes that the UBC team “plans to carry out directed evolution, a protein engineering technique that simulates natural evolution, with the goal of creating the most efficient sugar-removing enzyme.”
“I am optimistic that we have a very interesting candidate to adjust donated blood to a common type,” Withers said in the ACS statement. “Of course, it will have to go through lots of clinical trials to make sure that it doesn’t have any adverse consequences, but it is looking very promising.”
“But if it’s a sustainable technique, the implications are multifold,” he noted. “Especially given the nature of the technique itself, which involves lopping off certain antigens (which are, in essence, simple sugars) from particular red blood cells. The question is whether it can be used on a wide-scale in a safe and efficient manner to create larger blood supplies in times of need.”
That certainly is the question. For decades, scientists have searched for the secret to creating universal blood and now it appears the answer may have been lurking inside our bodies all along. Clinical laboratories may soon see human microbiome become linked to even more discoveries that lead to new tests and diagnostic tools.
—Andrea Downing Peck