The research, published on April 26, highlights the discovery of gut bacteria enzymes that not only remove A and B antigens from red blood cells but also address other hurdles hindering the development of universal donor blood.
Maher Abou Hachem, Ph.D., a senior author of the study and gut bacteria researcher, emphasized the significance of the findings, stating, “We are close to being able to produce universal blood from group B donors, while there is still work to be done for the more complex group A blood.”
Blood donations must typically match type or come from O-negative donors, the universal blood type. Mismatched donations can lead to acute hemolytic reactions, where the immune system attacks transfused red blood cells.
The study builds upon previous research from about four decades ago, which identified gut enzymes capable of removing antigens characterizing type B blood cells. Despite earlier efforts producing cells that could be donated to individuals with other blood types, residual components triggered immune responses, impeding progress.
The current breakthrough stemmed from new findings that focused on identifying the components preventing converted red blood cells from achieving full compatibility. Collaborative efforts between researchers and Hachem’s lab led to the discovery that enzymes from the gut bacteria Akkermansia muciniphila could break down carbohydrate extensions of both type A and B antigens.
This discovery led to further investigation, with Mathias Jensen, a DTU Ph.D. student and first author of the study, leading a project screening combinations of 24 different A. muciniphila enzymes against hundreds of blood samples. Seven enzymes were identified capable of removing both antigens and their extensions, demonstrating improved compatibility in samples with blood type O.
Jensen expressed optimism, stating, “After more than three years of hard work and thanks to the efficiency of A. muciniphila enzymes and the joint expertise of involved groups, we provided the first evidence that the removal of extended A and B antigens improves ECO blood compatibility, thereby reviving hope for truly ABO-universal blood.”
The team has applied for a patent on the enzymes and conversion protocol, aiming for eventual commercialization for clinical use.