2. What is a blood group?
• Any variation or polymorphism "having
multiple forms". detected in the blood
could be considered a blood group,
restricted to blood cell surface antigen
generally to red cell surface antigen

3. Nomenclature
• The ABO blood group system was discovered by
Karl Land Steiner in 1901.
Red blood cells or erythrocytes are present in the blood
and contain certain proteins on their surface.
• These proteins are called antigens.
• The plasma which is the liquid part contains antibodies
which will attack certain antigens if they are present.
• There are various types of red blood cell antigens - the
ABO and rhesus types are the most important.
• By the time a person is six months old, he naturally will
have developed antibodies against the antigens his red
blood cells lack.

5. Blood Group “A”
• A blood group
individuals will have
type A antigens on
the surface of red
blood cells
• And anti-B antibodies
in plasma

6. Blood Group “B”
• B blood group
individuals will have
type B antigens on
the surface of red
blood cells
• And anti-A antibodies
in plasma.

7. Blood group AB
• AB blood group are
those who will have type
A and type B antigens on
the surface of red blood
cells
• And no antibodies to A or
B antigens in plasma.

8. Blood group “O”
• O blood group are
those who will have
neither type A or type
B antigens on the
surface of red blood
cells
• but will have anti-A
and anti-B antibodies
in plasma.

9. 1. The reason for the
presence of A and B
antibodies in blood is not
clearly understood.
2. Antibody normally do not
developed against unless
the body is exposed to the
antigen.
3. This means, for example,
that a person with type A
blood should not have type
B antibodies unless he has
received a transfusion of
type B blood, which contain
type B anti-gens

10. • Because people with type A blood (who never
have received a transfusion of type B blood) do
have type B antibodies,
• One possibility is that type A or type B antigens
on bacteria or food in the digestive tract
stimulate the formation of antibodies against
antigens that are different from one's own
antigens.
• Thus a person with type A blood would produce
type B antibodies against the B antigens on the
bacteria or food.
• In support of this hypothesis is the observation
that A and B antibodies are not found in the
blood until 2 months after birth

12. • Agglutinins
• Agglutinins

13. Donor and recipient
• A donor is a person who give blood
• A recipient is a person who received blood
•

15. • The six possible O 47%
combinations of
genes, as shown in
are OO, OA, OB, AA, A 41%
BB, and AB. These
combinations of
genes are known as B 9%
the genotypes, and
each person is one of
A B3%
the six genotypes.

19. •
A general view of the
molecular structure of
Elizabethkingia
meningosepticum N-
acetylgalactosaminidase in
complex with the NAD+
cofactor (in yellow) and the A
antigen on the surface of A
type red blood cells. The N-
acetylgalactosamine molecule
recognized and hydrolyzed by
the enzyme appears in red.
(Credit: Copyright AFMB -
CNRS 2007)

20. Rhesus factor
History of discoveries
• The Rhesus system is named after the Rhesus
monkey, following experiments by Karl Land
steiner and Alexander S. Wiener, which showed
that rabbits, when immunised with rhesus
monkey red cells, produce an antibody that also
agglutinates the red blood cells of many
humans. This factor was discovered in 1937
(publishing in 1940)

21. Rhesus factor
• Individuals either have, or do not have, the Rhesus
factor (or Rh D antigen) on the surface of their
red blood cells.
• This is usually indicated by 'RhD positive' (does have the
RhD antigen)
• or 'RhD negative' (does not have the antigen)
• This suffix is often shortened to 'D pos'/'D neg', 'RhD
pos'/RhD neg', or +/-.
• RhD+
• or RhD-
• In simplest terms, there may be prenatal danger to the
fetus when a pregnant woman is RhD-negative and the
biological father is RhD-positive.

22. • Rh + father Rh- mother
Rh+fetus

23. Hemolytic disease of the newborn
• Hemolytic disease of the newborn is also called
Erythroblastosis Fetalis. This condition occurs
when there is an incompatibility between the
blood types of the mother and the baby..
• hemolytic comes from two words: hemo (blood)
and lysis (destruction) or breaking down of red
blood cells
• erythroblastosis refers to the making of
immature red blood cells
• fetalis refers to the fetus

24.  When the condition is caused
by the RhD antigen-antibody
incompatibility, it is called
RhD Hemolytic disease of
the newborn (often called
Rhesus disease or Rh
disease
 Here, sensitization to Rh D
antigens (usually by feto-
maternal transfusion during
pregnancy) may lead to the
production of maternal anti-
RhD antibodies which can
pass through the placenta.
 This is of particular
importance to RhD negative
females because any
subsequent pregnancy may
be affected by the Rhesus D
hemolytic disease of the
newborn if the baby is Rh D
positive.

25. • Fetal-maternal hemorrhage
can occur due to trauma,
abortion, childbirth, ruptures
in the placenta during
pregnancy, or medical
procedures carried out during
pregnancy that breach the
uterine wall.
• In subsequent pregnancies, if
there is a similar
incompatibility in the fetus,
these antibodies are then
able to cross the placenta
into the fetal bloodstream to
attach to the red blood cells
and cause hemolysis.
• In other words, if a mother
has anti-RhD antibodies as a
result of previously carrying a
RhD-positive fetus, this
antibody will only affect a
fetus with RhD-positive
blood.

27. • The vast majority of Rh disease is preventable in
modern antenatal care by injections of IgG anti-
D antibodies (Rh(D) Immune Globulin).
• The incidence of Rhesus disease is
mathematically related to the frequency of RhD
negative individuals in a population, so Rhesus
disease is rare in East Asians and Africans,
• but more common in Caucasians.

28. Population data
The frequency of Rh factor blood types and the RhD neg allele gene differs in
various populations.
]
Population data for the Rh D factor and the RhD neg allele
Population Rh(D) Neg Rh(D) Pos
European Basque approx 35% 65%
Caucasian Approx 35 % 65%
American Blacks approx 35%16%approx 65%84%93%99%over
7%approx 1%less 1%less 1% 99%over 99%
Native American approx 35%16%approx 65%84%93%99%over
Indians 7%approx 1%less 1%less 1% 99%over 99%
African descent approx 35%16%approx 65%84%93%99%over
7%approx 1%less 1%less 1% 99%over 99%

29. Symptoms and signs in the Fetus:
Enlarged liver, spleen, or heart and fluid buildup in the fetus'
abdomen seen via ultrasound.
• Symptoms and signs in the Newborn:
1. Anemia which creates the newborn's pallor (pale
appearance).
2. Jaundice or yellow discoloration of the newborn's skin, sclera
or mucous membrane. This may be evident right after birth or
after 24 - 48 hours after birth. This is caused by bilirubin (one
of the end products of red blood cell destruction).
3. Enlargement of the newborn's liver and spleen.
4. The newborn may have severe edema of the entire body.
5. Dyspnea or difficulty breathing.