Transcript 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
–A
–B
– AB
–O
ANTIGEN PRESENT
A
B
AB
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
•
•
•
•
A
B
AB
O
ANTIGEN
A
B
AB
neither
ANTIBODY
anti B
anti A
neither
anti A antiB
BLOOD TYPE
O
A
B
AB
PERCENTAGE
45%
40%
11%
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/m
edicine/landsteiner/
• Go to this website and type some blood