4. 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
5. 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.
7. 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
8. 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.
9. 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.
10. 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.
11. 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
12. • 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
16. Donor and recipient
• A donor is a person who give blood
• A recipient is a person who received blood
•
18. • The six possible O 47%
combinations of genes,
as shown in are OO, OA,
A 41%
OB, AA, BB, and AB.
These combinations of
genes are known as the B 9%
genotypes, and each
person is one of the six
genotypes. A B3%
22. •
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)
23. 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)
24. 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.
26. 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
27. 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.
28. • 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.
30. • 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.
31. 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%
32. 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.