The Power of Blood!

Royal blood, bad blood, cold blood… We have a lot of ways to describe this most priceless of bodily fluids. And wherever you go in the world, people place great value in the power of blood. From people in rural Africa who refuse to supply so much as a finger-prick of blood to malaria researchers, believing that the taking of blood is witchcraft, to the Halloween revellers who cover themselves in fake blood for maximum scare-power.

But there are far more scientific stories to tell that are equally as fascinating as all the vampire tales. Take the puzzle of blood groups for example…

What’s your type?

To the naked eye, all blood looks the same, and yet you can’t give a patient a transfusion of whatever blood you have to hand. So what does your blood group actually mean? Let’s have a crash course of what you’ll find in a blood sample:

If you examined the red blood cells in a sample, you’d see proteins on the surface of them. These are called antigens and you’ll there are two types in human blood  – A antigens and B antigens. – that you’ll find in one of three combinations People with Blood group A have red blood cells that only have A antigens, Blood group B only have B antigens, Blood group AB has a combination of both. Some people have no antigens which we call Blood group O.

This little gif shows what happens in sickle cell disease. A tiny change in the genes causes some red blood cells to become shaped like a banana. This makes them sticky and which in turn causes ill health.

Austrian scientist Karl Landsteiner first described the blood grouping pattern of humans in the early 1900s. Since then, we haven’t managed to find out much more about what these antigens do. Blood group O is the most common and people with blood group O seem to manage just fine without any A or B antigens. In fact, we’ve found that people belonging to the A and B blood groups may be more susceptible to certain diseases. For example, people with group B seem to get more serious E. coli infections and those with group A are more likely to be affected by smallpox.

We have also discovered that the ABO blood grouping is waaaay too simple a way to catalogue bloody groups. There are as many as 20 different blood groups made up of a large variety of combinations of antigens. There’s the Rhesus factor (the Positive or Negative addition to your ABO blood group) which indicates whether you have the rhesus antigen on your red blood cells. But there are also the Diego, Kidd, Kell and Duffy blood groups. Your personal blood type is more like a barcode showing whether or not your red blood cells present or don’t present each of the blood group antigens.

Understanding blood = better medicine

Understanding blood group antigens is critical to our ability to treat disease and trauma that leads to blood loss. The first transplant took place in 1907 just months after Prof Landsteiner’s research was published. Now, our ability to take blood from healthy donors store it and transfuse it when someone needs it is a commonplace. N.B. The process might be something we can take for granted, but the heroic act of donating blood it never is. Massive kudos to all you blood donors out there! There’s never quite enough – particularly of the rarer combinations of blood group antigens.

This is one area of medicine where stem cell technology may make a huge difference. I know, there’s a lot of stigma attached to stem cell technology, but it doesn’t deserve its reputation and what’s more, people can join the stem cell registry on a research-only basis. This would allow scientists and doctors to use humans rather than animals which would make their findings more accurate. The wider the base, the more research and scenarios can be studied. Stem cell therapy thoroughly researched could have vast implications in fighting all manner of diseases. Now wouldn’t that be amazing?