Karl Landsteiner discovered the main human blood groups (A, B, AB and O) in 1901. This discovery allowed safer blood transfusions by preventing the mixing of incompatible blood, which can cause fatal reactions. The blood groups are determined by antigens on red blood cells and corresponding antibodies in plasma. People with type O blood are universal donors as their red blood cells lack A and B antigens, while people with type AB blood are universal recipients as they lack antibodies against A and B antigens. Compatible blood groups are required for safe transfusions to avoid agglutination of red blood cells.

2. Blood Groups & Blood TypingBlood Groups & Blood Typing

3. Blood Groups & Blood TypingBlood Groups & Blood Typing
Discovery of Blood Groups
• Experiments with blood transfusions have been
carried out for hundreds of years. Many patients
have died and it was not until 1901, when the
Austrian Karl Landsteiner discovered human
blood groups, that blood transfusions became
safer.
• Mixing blood from two individuals can lead to blood
clumping or agglutination. The clumped red cells
can crack and cause toxic reactions. This can have
fatal consequences. Karl Landsteiner discovered
that blood clumping was an immunological reaction
which occurs when the receiver of a blood
transfusion has antibodies against the donor blood
cells.

4. Blood Groups & Blood TypingBlood Groups & Blood Typing
Discovery of Blood Groups
• Karl Landsteiner's work
made it possible to
determine blood types and
thus paved the way for
blood transfusions to be
carried out safely. For this
discovery he was awarded
the Nobel Prize in
Physiology or Medicine in
1930.

5. Blood Groups & Blood TypingBlood Groups & Blood Typing
What are the different blood groups?
• The differences in human blood are
due to the presence or absence of
certain protein molecules called
antigens and antibodies.
• The antigens are located on the surface
of the red blood cells and the
antibodies are in the blood plasma.
• Individuals have different types and
combinations of these molecules. The
blood group you belong to depends on
what you have inherited from your
parents.

6. A
B
AB
O

7. Antige
n
Antigen on the Red Blood Cell Membrane
Antibodies in the Plasma
Antibody
Antibody
Antibody
Antibody
Antibody
Antibody
Antibody
Antibody
Antibody

8. B
B
B
B
B
B
B
B
A
A - Antigen on the Red Blood Cell Membrane
B - Antibodies in the Plasma

9. A
A
A
A
A
A
A
A
B
B - Antigen on the Red Blood Cell Membrane
A - Antibodies in the Plasma

10. AB
A and B - Antigen on the Red Blood Cell Membrane
No - Antibodies in the Plasma

11. B
A
B
B
A
A
B
A
No - Antigen on the Red Blood Cell Membrane
A and B - Antibodies in the Plasma

12. Blood Groups & Blood TypingBlood Groups & Blood Typing
AB0 blood grouping system
• According to the AB0 blood typing
system there are four different kinds of
blood types: A, B, AB or 0 (null).

13. Blood Groups & Blood TypingBlood Groups & Blood Typing
AB0 blood grouping system
Blood group A
If you belong to the blood group A, you have A
antigens on the surface of your red blood cells and B
antibodies in your blood plasma.
Blood group B
If you belong to the blood group B, you have B
antigens on the surface of your red blood cells and A
antibodies in your blood plasma.

14. Blood Groups & Blood TypingBlood Groups & Blood Typing
AB0 blood grouping system
Blood group AB
If you belong to the blood group AB, you have both A
and B antigens on the surface of your red blood cells
and no A or B antibodies at all in your blood plasma.
Blood group 0
If you belong to the blood group 0 (null), you have
neither A or B antigens on the surface of your red
blood cells but you have both A and B antibodies in
your blood plasma.

15. Blood Groups & Blood TypingBlood Groups & Blood Typing
AB0 blood grouping system
Blood Group Antigen on RBC Antibody in Serum Diagram
O none A and B
A A B
B B A
AB A and B None

16. Blood Groups & Blood TypingBlood Groups & Blood Typing
Blood Compatibility and
Transfusions
Who is the universal donor?
Who is the universal acceptor?

17. O
AB
BA

18. Blood Groups & Blood TypingBlood Groups & Blood Typing
Rh factor blood grouping system
• Many people also have a so called Rh factor on the
red blood cell's surface.
• This is also an antigen and those who have it are
called Rh+. Those who haven't are called Rh-.
• A person with Rh- blood does not have Rh antibodies
naturally in the blood plasma (as one can have A or B
antibodies, for instance). But a person with Rh- blood
can develop Rh antibodies in the blood plasma if he
or she receives blood from a person with Rh+ blood,
whose Rh antigens can trigger the production of Rh
antibodies.
• A person with Rh+ blood can receive blood from a
person with Rh- blood without any problems.

19. A Rh+ B Rh+ AB Rh+ 0 Rh+
A Rh- B Rh- AB Rh- 0 Rh-
Blood Groups & Blood TypingBlood Groups & Blood Typing
Blood group notation
According to the blood grouping
systems, you can belong to either
of following 8 blood groups:

20. Blood Groups & Blood TypingBlood Groups & Blood Typing
Blood Compatibility and Transfusions
• The ABO and Rh groups are factored
together to identify 1 of the previous 8
blood types.
• During blood transfusions, doctors
must be aware of these blood types to
prevent agglutination of the recipient’s
blood.

21. Type AB (3%)
Type B (9%)
Type A (42%)
Type O (46%)
Percentage of blood types amongst all Canadians
Average percentage of blood types required
by hospitals in Canada
O positive is the most common blood type, shared
by (and required by) 39% of the Canadian
population. O negative blood is carried by only 7%
of the population but, unlike other blood types, it
can be given to patients of any blood group in
emergency situations.

22. Greg is a 17-year-old who was
admitted to hospital following a
car crash. He suffered a crushing
injury to his right leg. He is booked
for surgery and his blood group is
Type AB.
Who in your group can
give blood to Greg?

23. Benjamin is a three-month-old who
was born with a major heart defect.
He requires surgery to enable him
to live past his first birthday.
Benjamin’s blood group is Type B.
Who in this class can
give blood to Benjamin?

24. Sarah is a five-year-old Leukemia
patient. She visits the hospital
regularly to receive blood
transfusions that she requires to
continue fighting her disease.
Sarah has Type A blood.
Who in this class can
give blood to Sarah?

25. Bill is a 50-year-old father of three
teenage children. He is booked for
heart surgery as two of the arteries
in his heart are blocked. Bill’s
blood group is Type O.
Who in this class can
give blood to Bill?

26. John is a 60-year-old man that has
just been admitted to the
Emergency Department vomiting
large amounts of blood. His wife
tells the physician that her
husband has two stomach ulcers.
The physician orders blood right away
for this man.
What blood group will
this man receive?

27. Sam is a 20-year-old man who
was shot in the lower abdomen
while deer hunting. While in the
Emergency Department he
received three units of Type O
negative blood. He is now booked
for surgery and we now know that
his blood is Type AB.
Who in this class can
give blood to Sam?

28. Blood Groups & Blood TypingBlood Groups & Blood Typing
Erythroblastosis Fetalis
• Erythroblastosis fetalis is a blood disease of a
newborn infant caused by blood group
incompatibility between mother and child. With an
Rh-negative mother and an Rh-positive father, the
possibility exists that the fetus will be Rh positive.
Blood mixing during pregnancy permits fetal red
blood cells to enter the maternal circulation,
causing the mother to start to produce antibodies
against the Rh antigen from the fetus.
• Maternal antibodies pass through the placenta
into the fetus, where an excessive destruction of
fetal red blood cells occurs. When this destruction
begins during pregnancy, stillbirth may result.

29. Blood Groups & Blood TypingBlood Groups & Blood Typing
Erythroblastosis Fetalis

30. Blood Groups & Blood TypingBlood Groups & Blood Typing
Erythroblastosis Fetalis
• There is little danger of damage to the fetus during the
first pregnancy because not enough antibodies have
been produced by the mother. However, by the second
pregnancy, sufficient antibodies will have accumulated in
the mother’s bloodstream to cause increasing danger.
• The formation of maternal anti-Rh antibodies has been
largely prevented in Canada by the injection of human
immune globulin into the mother within 72 hours after
delivery. This globulin contains antibodies against the
Rh-positive fetal red blood cells, destroying them before
the maternal bloodstream reacts by producing its own
anti-Rh antibodies. Thus during the next pregnancy
there will be few, if any, antibodies in the maternal
bloodstream to destroy the fetal Rh-positive blood cells.

31. Blood Groups & Blood TypingBlood Groups & Blood Typing

32. Blood Groups & Blood TypingBlood Groups & Blood Typing
?

33. Blood Groups & Blood TypingBlood Groups & Blood Typing

34. http://nobelprize.org/medicine/educational/landsteiner/readmore.html