Blood Typing

Blood Typing

Blood Groups

• Karl Landsteiner in the 1900’s discovered blood typing.

ABO Blood Groups

• Based on 2 Antigens (agglutinogens)

• 4 blood types: A, B, AB, O

• Blood antigens are genetically coded located on the surface of RBC membrane

• Antigen found on RBC corresponds to blood type.

Blood Groups

• TYPE ANTIGEN PRESENT

– A A– B B– AB AB– O Neither A nor B

Blood Groups

• Antibodies are called agglutinins they develop after birth in the plasma

• You will have the antibody for the antigen that is NOT present.

• If you have A blood you have the A antigen on your RBC you will develop the B antibody

Antibody

• TYPE ANTIGEN ANTIBODY

• A A anti B

• B B anti A

• AB AB neither

• O neither anti A antiB

BLOOD TYPE PERCENTAGE

O 45%

A 40%

B 11%

AB 4%

• A reaction outside the body between antigens and antibodies result in agglutination which means the blood cells clump together.

• A reaction within the body between antigens and antibodies results in hemolysis which means the red cells burst

Rh Factors

• 1946 Landsteiner, Levine and Weiner did research on the rhesus monkey and developed the Rh factor

• Three genes code for the antigen on red cells- C, D, E

• Blood Types based on Rh

• Rh positive means the Rh antigen is present on the RBC (+)

• Rh negative means the Rh antigen is not present on the RBC (-)

• Rh negative people that receive Rh positive blood can have the immune system develop Rh antibodies that will remain in the blood

Erythroblastosis Fetalis

• Hemolytic Disease of the Newborn

• A Rh negative mom may be exposed to an Rh antigen from the blood of a Rh positive baby during pregnancy or birth.

• If Rh + cell enters Rh- mom the mother’s immune system will respond and produce antibodies against the Rh positive blood antigen

• In pregnancies thereafter Rh antibody may cause the placenta and cause RBC hemolysis in fetus. The baby will be anemic and very ill.

• This can be avoided by giving a Rh- mom antibodies in the form of a RhoGam shot within 72 hours after delivery of every Rh+ child

Blood Typing

• Blood typing is when blood samples are tested with known antiseras that contain known antibodies

O+

A+

B+

AB+

B+

o-

Cross Matching

• Cross matching is where typing the donor’s RBC’s are mixed with the recipients serum to check for compatibility before a blood transfusion

• http://nobelprize.org/educational_games/medicine/landsteiner/

• Go to this website and type some blood