ImmunohematologyStudy of human blood groups

Karl Landsteiner

• 1901 Began studies of blood antigens, blood transfusions, genetic inheritance of blood, use of blood types in a court of law

• Identified and named the blood group A, B, AB, O in 1909

• Received the Nobel Prize in 1930

Student Question: Do animals have blood types?Yes- Dogs have 4 types, cats have 11 and cows have 800.

Antigen- (agglutinogens) proteins found on the surface of cells, in this case red blood cells

Antibodies -(immunoglobulins)- serum (plasma) proteins

Antibodies

Antibodies

Antibodies

Where do antibodies come from?

• We are not born with them.

• Blood antibodies probably come from the foods we eat such as meat and dairy products.

• Other antibodies found in your body develop against diseases.

B. Principle of Agglutination- What's happening in the picture?

Agglutination (clumping) occurs when antibodies not normally present in the blood are added.

This is what it looks like under the microscope.

Using the principal of agglutination to determine blood type

Take a known antiserum and add it to blood.

Example: Anti-A antiserum will cause agglutination in A blood.

Clumping

What is this person’s blood type?A

Rh Factor

• There are other antigens present in blood- Rh antigens

• (Tested in the same way you test A and B antigens)

• If your blood clots in the presence of Rh antibodies you are Rh +

• If your blood does not clot in the presence of Rh antibodies you are Rh -

Frequency of blood types in the US

Which is the most common?

Which is the least common?