Introduction to Hematology

Blood Typing
In 1901, Karl Landsteiner reported that blood had TYPES. By matching these types one could achieve success in blood transfusion.

The basis of these types are specific proteins called antigens that are found on the surface of red blood cells and antibodies found in the plasma.

There are four basic types:

1. Type A with A antigens on the red cells and anti B antibodies in the plasma

2. Type B with B antigens on the red cells and anti A antibodies in the plasma

3. Type AB with both A and B antigens on the red cells and no type antibodies in the plasma

4. Type O with no type antigens on the red cells and both anti A and anti B antibodies in the plasma

Find out more about blood types in the population.

If we take the antibodies from the plasma of a person with type A blood (anti B antibodies) and mix them with the blood (remember...mostly red cells) of a person with type B blood, the antibodies attach themselves to the red cells and cause the red cells to clump together.

• See Examples of Blood Typing

These types (and other less striking types) must be properly matched for a blood transfusion to work.