Blood Types

Ch. 19-2

Blood Types

• Blood cells have surface markers called antigens

• ABO Blood Group– RBC with A antigens – A blood type– RBC with B antigens – B blood type– RBC with A and B antigens – AB blood type– RBC with no antigens – O blood type

Blood Types

• Blood plasma contains proteins called antibodies

• Antibodies will react with antigens if mixed– Type A blood – A antigens, anti-B antibodies– Type B blood – B antigens, anti-A antibodies– Type AB blood – A and B antigens, no antibodies– Type O blood – no antigens, anti-A and anti-B

antibodies

Blood Types

Transfusions

• Transfusion – transfer of whole blood or blood components (RBC or plasma)

• Agglutination – clumping of RBCs, hemolysis occurs, kidney damage and death can result– This only causes problems between recipient antibodies and donor

antigens– Donor antibodies become diluted in blood plasma

• Example– (recipient) A person receives blood from (donor) B person– Recipients blood contains anti-B antibodies– Donor’s blood contains B antigens– Antigen/antibody complex forms

Who can donate/receive to/from who?

Rh Blood Group

• Antigen was discovered in the rhesus monkey• Rh+ people have the Rh antigen, Rh- people do

not have the Rh antigen• People do not naturally have anti-Rh antibodies• If Rh- person receives blood from Rh+ person,

immune system will make anti-Rh antibodies• If they receive Rh+ blood again, the anti-Rh

antibodies will cause agglutination

Who can donate/receive to/from who?

• + should not be given to –• + can receive + or –• - can give to + or –• Universal donor – O-• Universal recipient – AB+

Hemolytic Disease of Newborn (HDN)

• Fetal blood can cross placenta into maternal blood stream

• If baby is Rh+ and mother is Rh-, mother’s immune system starts making anti-Rh antibodies

• During the next pregnancy the antibodies can cross into the fetal blood

• If the second fetus is Rh+, agglutination can occur

HDN

Review of Inheritance

• Blood type Punnett squares• Rh Punnett squares – Rh+ is dominant to Rh-– Rh+ could have Rh+/Rh+– Rh + could have Rh+/Rh-– Rh- must be Rh-/Rh-