The Conversation – 26th July 2017
By Robert Flower
There are many molecules on the surface of red blood cells that vary between individuals, and these form the basis of blood groups. The most commonly recognised of these are the ABO blood groups, and Rh antigens (which are signified by the “positive” or “negative” that comes after A, B or O on your blood type).
What you may not know is that there are 34 other blood group systems with more than 300 known variants. These are all classified by the “antigens” found on the surface of our red blood cells. Antigens are molecules (most often proteins, but also carbohydrates) capable of provoking our immune systems to attack.
People also have antibodies – the proteins that attack infections and other foreign bodies. So when a patient needs someone else’s blood transfused into them, we have to make sure they don’t have the type of antibodies that will attack the antigens on the blood the donor has provided for them.
We do this by identifying the blood group the antibody reacts with and then matching blood from donors whose blood type has been extensively tested and established. Additional blood typing is carried out when an antibody to a blood cell antigen has been identified in a patient. READ MORE AT: https://theconversation.com/blood-groups-beyond-a-b-and-o-what-are-they-and-do-they-matter-75063