Blood...Composition & Functions.........

BLOOD: Composition & Functions
BY
Dr.V.S. Neharkar,M.Pharm,Ph.D
Dept. of Pharmacology,
RMDIPER,Chinchwad,Pune

Blood is a liquid connective tissue. It provides one of
the means of communication between the cells of different
parts of the body and the external environment, e.g. it
carries. Different system are in constant contact,
communication & synchronized physiology due to
circulatory system :
Act as internal transport system
 Considered a connective tissue: contains
 Cells
 a liquid ground substance (called plasma)
 dissolved protein fibers.

• The normal pH range of blood is 7.35 to 7.45,which is slightly
alkaline. The venous blood normally has a lower pH than the arterial
blood because of presence of more Carbon dioxide.
pH of blood
• The temperature of the blood is 38°C(100.4°F), about 1°Chogher than
oral or rectal body temperature.
Temperature
• ‘Viscosity’ means thickness or resistance to flow. Blood is about 3-5
times denser & more viscous(thicker) than water & feels slightly sticky.
Viscosity is increased by the presences of blood cells & plasma
proteins. This thickness contributes to normal blood pressure.
Viscosity
• The colour of blood varies with its oxygen content. Arterial blood is
bright red due to it’s high level of oxygen. Venous blood has given up
much of it’s oxygen in tissues & thus has a darker, dull red colour.
Colour
• Blood constitutes about 20% of extracellular fluid, amounting to 8%
of total body mass. The blood volume is 5L to 6L(1.5gal) in average
sized adult male & 4L to 5L(1.2gal) in an average sized adult female.
Amount

Three major functions of blood-
1. Transportation
2. Regulation
3. Protection
1.Transportation
• Respiratory
Red blood cells or erythrocytes transport Oxygen from lungs to cells and
Carbon dioxide from cells to lungs.
• Nutritive
Blood absorb nutrients from digested foods in gastrointestinal tract and
transport to all the cells in body.
• Excretory
Metabolic wastes, excess water, ions and other molecules not needed by
the body are carried by the blood to the kidneys and excreted in the urine

Functions of blood
Regulation
• Hormonal- Blood carries hormones from their site of origin to
distant target tissues , where they perform the regulatory functions
• Temperature Blood is responsible to carry body heat to the surface
in high temperature environment as well as to keep body heat in
within low temperature environment
Protection
• Clotting-The clotting mechanism protects against blood loss when
vessels are damaged
• Immune The immune function of blood is performed by the
leukocytes that protects against many disease causing agents

TRANSPORTATION
• Respiration
• Nutrient carrier from
GIT
• Transportation of
hormones from
endocrine glands
• Transports metabolic
wastes
REGULATION
• Regulates pH
• Adjusts and
maintains body
temperature
• Maintains water
content of cells
PROTECTION
• WBC protects
against disease
by phagocytosis
• Reservoir for
substances like
water, electrolyte
etc.
• Performs
haemostasis
Functions of blood

Composition of the Blood
• Blood consists of formed elements that are
suspended and carried in a fluid called plasma
Blood Cells (rbc, wbc, platelets) = 45%
Blood Plasma (water, proteins, amino acids..etc) = 55%

• Erythrocytes (or red blood cells)
– form the lower layer of the centrifuged blood
– typically make up about 44% of a blood sample
• Buffy coat
– makes up the middle layer
– thin, slightly gray-white layer composed of cells called
leukocytes (or white blood cells) and cell fragments called
platelets
– forms less than 1% of a blood sample
• Plasma
– straw-colored liquid that rises to the top
– generally makes up about 55% of blood
Components of Blood

Composition of the Blood-Plasma

Composition of the Blood-Formed elements

Formed
Elements
Erythrocytes Leukocytes
Granular
Leukocytes
Neutrophils Basophils Eosinophils
Agranular
Leukocytes
Lymphocytes
T-cell B-cell
Natural Killer
cells
Monocytes
Fixesd
Macrophages
WanderinMac
rophages
Platelets
Formed Elements in the Blood

Hemoglobin
Female: 12-16 g/100 ml
male: 13-18 g/100 ml
Mean RBC count
Female: 4.8 million/l
male: 5.4 million/l
Platelet counts 130,000-360,000/l
Total WBC counts 4,000-11,000/l
General Range of Whole Blood

When formed elements are removed from blood, a straw colored liquid called
blood plasma is left.
Chemical composition of blood plasma-
WATER(91.5%)
Liquid portion of blood. Acts as solvent and suspending medium
for components of blood; absorbs, transports and releases heat.
PLASMA
PROTEIN(7.0%)
Exert colloid osmotic pressure , which helps maintain water
balance between blood and tissues and regulates blood volume.
ALBUMIN
Smallest and most numerous blood plasma proteins; produces
by liver. Transports proteins for several steroid hormones and for
fatty acids.
GLOBULINS
Produces by liver and plasma cells, which develop from B-
lymphocytes. Antibodies help attack viruses and bacteria. Alpha
and beta globulins transport iron, lipids and fat soluble vitamin.
FIBRINOGEN
Produces by liver. Plays essential role in blood clotting.
PLASMA

OTHER
SOLUTES(1.5%)
ELECTROLYTES
Inorganic salts. Positively charges ions(cations) include
Na+
,K+
,Ca+
,Mg2+
;
Negatively charged ions(anions) include Cl-
,HPO4
2-
,SO4
2-
,HCO3
-
. Help maintain osmotic pressure and plays essential
roles in function of cells.
NUTRIENTS
Products of digestion pass into blood for distribution to all body
cells. Includes amino acids(from proteins), glucose(from
carbohydrates), fatty acids and glycerol(from triglycerides),
vitamins and minerals.
GASES
Oxygen, Carbon dioxide and Nitrogen. More O2 is associated
with hemoglobin inside red blood cells; more CO2 is dissolved
in plasma. N2 is present but has no known functions in the
body.
REGULATORY
SUBSTANCES
Enzymes, produces by body cells, catalyze chemical reactions.
Hormones, produced by endocrine glands, regulate
metabolism, growth and development. Vitamins are cofactors
for enzymatic reactions.
WASTE PRODUCTS
Most are breakdown products of protein metabolism and are
carried by blood to organs of excretion. Include urea, uric acid,
creatine, creatinine, bilirubin and ammonia.

FORMED ELEMENTS
NAME AND
APPEARANCE
NUMBER
CHARACTERSTIC
S*
FUNCTIONS
Red Blood
Cells(RBCs) or
Erythrocytes
4.8 million/µL in
females
5.4 million/µL in
males
7-8 µm diameter,
biconcave discs,
without nuclei; live
for about 120 days.
Hemoglobin within
RBCs transports most
of the oxygen and part
of carbon dioxide in the
blood.
White Blood
Cells(WBCs) or
Leukocytes
5000-10,000/µL
Most live for a few
hours to a few days.
Some called T and
B memory cells can
live for many years.
Combat pathogen and
other foreign
substances that enter
the body.
Granular
Leukocytes
Neutrophiles
60%-70% of all
WBCs
10-12µm diameter;
nucleus has 2-5
lobes connected by
thin strands of
chromatin;
cytoplasm has very
fine, pale, lilac (pale
violet) granules.
Phagocytosis.
Destruction of bacteria
with lysozymes,
defensins and strong
oxidants, such as
superoxide anion,
hydrogen peroxide,
and hypochlorite anion.

Eosinophils
2-4% of all
WBCs
10-12µm diameter;
nucleus usually has 2
lobes connected by s
thick strand of chromatin;
large, red-orange
granules fill the
cytoplasm.
Eliminates parasites, such as
worms which are too big to be
phagocytosed; phagocytes
antigen-antibody complexes
& combat the effects of
histamine in allergic reactions
Basophils
0.5-1% of all
WBCs
8-10µm diameter; nucleus
has 2 lobes; large
cytoplasmic granules
appear deep blue-purple.
Liberate heparin, histamine
and serotonin in allergic
reactions that intensify the
overall inflammatory
response.
Agranular
Leukocytes
Lymphocyt
es(T cells,
B cells &
natural
killer cells)
20-25% of all
WBCs
Small lymphocytes are 6-
9µm in diameter; large
lymphocytes are 10-14µm
in diameter; nucleus is
round or slightly indented;
cytoplasm forms a rim
around the nucleus that
looks sky blue; the larger
the cell, the more
cytoplasm is visible.
Medium immune response,
including antigen-antibody
reactions. B cells develop into
plasma cells, which secrete
antibodies, T cells attack
invading viruses, cancer cells,
and transplanted tissue cells.
Natural killer calls attach a
wide variety of infectious
microbes and certain
spontaneously arising tumor

Monocytes
3-8% of all
WBCs
12-20µm
diameter; nucleus
is kidney shaped
or horseshoe
shaped.
Cytoplasm is blue-
grey and has
foamy
appearance.
Acts on the
hypothalamus, causing
the rise in body
temperature with
microbial infections;
stimulates the production
of some globulins by the
liver; enhances the
production of activated T-
lymphocytes;
Phagocytosis
Platelets(Thrombocytes)
150,000-
400,000/µL
2-3µm diameter
cell fragments that
live for 5-9days;
contains many
vesicles but no
nucleus.
Form platelet plug in
homeostasis; release
chemicals that promote
vascular spasm and
blood clotting.

90% Water
8% Solutes:
• Proteins
– Albumin (60 %)
– Alpha and Beta Globulins
– Gamma Globulins
– fibrinogens
• Gas
• Electrolytes
Blood Plasma Components-55%

Three Types of Blood Cells
Red blood cells (erythrocytes)
White blood cells (leukocytes)
Platelets (thrombocytes)

The constituents of plasma are water (90 to 92%) and dissolved
substances, including:
• plasma proteins: albumins, globulins (including antibodies), fibrinogen,
clotting factors
• inorganic salts (mineral salts): sodium chloride, sodium bicarbonate,
potassium, magnesium, phosphate, iron, calcium, copper, iodine, cobalt
• nutrients, principally from digested foods, e.g. monosaccharides
(mainly glucose), amino acids, fatty acids, glycerol and vitamins
• organic waste materials, e.g. urea, uric acid, creatinine
• hormones, e.g growth hormon,insulin etc
• enzymes, e.g. certain clotting factors
• gases, e.g. oxygen, carbon dioxide, nitrogen.
• Antibodies,protective substance produce by blood cells
Plasma Composition

 The most abundant materials in plasma are the plasma
proteins.
 Make up about 7% of the plasma.
 6 and 8 grams of protein in a volume of 100 milliliters of
blood
 The plasma proteins include:
 albumins
 globulins
 fibrinogen
 regulatory proteins
Plasma Proteins

Plasma Proteins – Albumins
 Smallest and most abundant of the plasma proteins.
 make up approximately 58% of total plasma
proteins
 Regulate water movement between the blood and
interstitial fluid.
 Albumins act as transport proteins that carry ions,
hormones, and some lipids in the blood.

Plasma Proteins – Globulins
 Second largest group of plasma proteins, forming
about 37% of all plasma proteins.
 Smaller alpha-globulins and the larger beta-globulins
primarily bind, support, and protect certain water-
insoluble or hydrophobic molecules, hormones, and
ions.
 Gamma-globulins: Also called immunoglobulins or
antibodies.
 Produced by some of our defense cells to protect the
body against pathogens that may cause disease.

Plasma Proteins – Fibrinogen
 Makes up about 4% of all plasma proteins.
 Responsible for blood clot formation.
 Following trauma to the walls of blood vessels,
fibrinogen is converted into long insoluble strands of
fibrin, which is the essence of a blood clot.

Plasma Proteins – Regulatory Proteins
 Form a very minor class of plasma proteins.
 <1% of total plasma proteins
 Include enzymes to accelerate chemical reactions in
the blood and hormones being transported
throughout the body to target cells.

Solutes
 Plasma is an extracellular fluid (ECF).
 it includes all body fluids that are not found inside cells
 Plasma is somewhat like interstitial fluid, in that
 both have similar concentrations of nutrients, waste
products, and electrolytes
 Concentration of dissolved oxygen is higher in plasma than
in interstitial fluid, because the cells take up and use the
oxygen from the interstitial fluid during energy production.

Solutes
 Difference in concentration ensures that oxygen will
continue to diffuse from the blood into the tissues.
 Difference in concentration ensures that carbon
dioxide will readily diffuse from the interstitial fluid
into the blood, where it will be carried to the lungs
and discharged from the body.

Formed Elements in the Blood
 Erythrocytes
 make up more than 99% of formed elements
 primary function is to transport respiratory gases in the
blood
 Leukocytes
 make up less than .01% of formed elements
 contribute to defending the body against pathogens
 Platelets
 make up less than 1% of formed elements
 help with blood clotting

Red blood cells- These are circular biconcave non-nucleated discs with a
diameter of about 7 microns. Measurements of red cell numbers, volume and
haemoglobin content are routine and useful assessments made in clinical
practice
1) biconcave shape
2) no nucleus
 extra space inside
3) contain haemoglobin
 Transport oxygen and
carbon dioxide to and
from the tissues and
the lungs
increases the surface area so more oxygen can be
carried

Hemoglobin in Erythrocytes
 Every erythrocyte is filled with approximately 280 million
molecules of a red-pigmented conjugated protein called
hemoglobin gives red color to blood. Synthesized inside the
immature erythrocytes in red bone marrow.
 Transports oxygen and carbon dioxide, and is responsible
for the characteristic bright red color of arterial blood.
 Hemoglobin that contains no oxygen has a deep red color
that is perceived as blue because the blood within these
veins is observed through the layers of the skin and the
subcutaneous tissue.
 Made up of two component
Heme- Non-protein iron portion.
Globin-Protein portion

Hemoglobin in Erythrocytes
 Each hemoglobin molecule consists of four protein building blocks,
called globins.
 Alpha (a) chains
 Beta (b) chains.
 All globin chains contain a nonprotein (or heme) group:
 ring shaped
 an iron (Fe) ion in its center.
 Oxygen binds to these iron(heme) ions to form Oxyhemoglobine for
transport in the blood.
 Each hemoglobin molecule:
 four iron ions
 is capable of binding four molecules of oxygen.
 Normal Count
Infants -14 to 20 g/100ml of blood.
Male - 12 to 16 g/100ml of blood.
Female - 12 to 14 g/100ml of blood.

When there is a high concentration of oxygen e.g in the
alveoli haemoglobin combines with oxygen to form
oxyhaemoglobin. When the blood reaches the tissue which
have a low concentration of oxygen the haemoglobin
dissociates with the oxygen and the oxygen is released into
body tissues
Function of Haemoglobin
VideoOxygen Transport.mp4

• Also called hematopoiesis
• Is the process of Production or development of
bloos cells.
• Occurs in red bone marrow
• Blood cells derived from stem cells called
hemopoietic stem cell.
• Blood cells are derived from in the marrow of
veterebra, ribs, sternum, clavicle, pelvic.
Hemopoiesis

Hemopoiesis/Erythropoiesis
Erythropoiesis is the process by which the
origin, development and maturation of erythrocytes
occur. Hemopoiesis is the process which includes
origin, development and maturation of all the blood
cells.
The process of development of red blood cells
from pluripotent stem cells takes about 7 days and
is called erythropoiesis .

SITE OF ERYTHROPOIESIS
IN FETAL LIFE
During embryonic life, the erythropoiesis occurs in three stages.
Mesoblastic stage: During the first two months of intrauterine life, the
primitive red blood cells are produced from mesenchyme of yolk sac.
Hepatic stage: From third month of intrauterine life, liver is the main organ
that produces red blood cells. Some erythrocytes are also produced from
spleen and lymphoid organs.
Myeloid stage: During the last three months of intra uterine life, the red
blood cells are produced red bone marrow and liver.

POSTNATAL LIFE AND IN ADULTS
In newborn babies, growing children and adults, the blood cells are
produced only from the red bone marrow.
1. Up to the age of 5 to 6 years: The red blood cell produced in
red bone marrow of all bones.
2. From 6th year up to 20th year: The red blood cell produced by
red bone marrow of long bones and the membranous (flat) bones.
3. After the age of 20 years: The red blood cells produced from all
membranous bones like vertebra, sternum, ribs, scapula, iliac bones
and skull bones and from the ends of long bones. After 20 year age,
the shaft of the long bones becomes yellow bone marrow because
of fat deposition and looses the erythropoietic function. During
disorders of bone ,the red blood cells are produced in the spleen.

POSTNATAL LIFE AND IN ADULTS
In newborn babies, growing children and adults, the blood cells
are produced only from the red bone marrow.
1. Up to the age of 5 to 6 years: The red blood cell produced in
red bone marrow of all bones.
2. From 6th year up to 20th year: The red blood cell produced by
red bone marrow of long bones and the membranous (flat)
bones.
3. After the age of 20 years: The red blood cells produced from
all membranous bones like vertebra, sternum, ribs, scapula,
iliac bones and skull bones and from the ends of long bones.
4. After 20 year age, the shaft of the long bones becomes yellow
bone marrow because of fat deposition and looses the
erythropoietic function. During disorders of bone ,the red
blood cells are produced in the spleen.

SITES OF HEMOPOIESIS
 Active Hemopoietic marrow is
found, in children throughout the:
• Axial skeleton:
Cranium
Ribs.
Sternum
Vertebrae
Pelvis
• Appendicular skeleton:
Bones of the Upper & Lower
limbs
 In Adults active
hemopoietic marrow is
found only in:
• The axial skeleton
• The proximal ends of
the appendicular
skeleton.

STAGES OF ERYTHROPOIESIS
The various stages
between stem cell and
matured red blood cell are
as :
1 Proerythroblast
2. Early normoblast
3. Intermediate normoblast
4. Late normoblast
5. Reticulocyte and
6. Matured erythrocyte.

The first cell of the Red Blood Cell series is the
PROERYTHROBLAST. Because of excessive stimulation, large
amount of these cells are formed from the CFU-E (Colony
forming Unit-E) Stem cells.
After the formation of the PROERYTHROBLAST it divides
multiple times, forming mature red blood cells. The first cell
formed is called as BASOPHILIC ERYTHROBLAST. These, cells
are called as Basophilic as they stain Basic dyes.
The cell at this stage contains very little Hemoglobin. In
next generations the cells get filled with Hemoglobin to about
34%, & the size of nucleus shrinks.

Finally, the nucleus is absorbed & extruded from the
cell. Even, the endoplasmic reticulum also gets absorbed. The
cell of this stage is called as RETICULOCYTE.
It is called reticulocyte because it still contains the
Basophilic Material, consisting of remaining of Golgi apparatus,
Mitochondria & few other Cytoplasmic Organelles. During the
stage of Reticulocyte the cells passes from Bone Marrow to the
Blood Capillaries.
This action is called as the Diapedesis (passing through
pores of capillary membrane). Any remaining Basophilic
Material in the Reticulocyte normally gets disappear within 1 to
2 days, and then the cell is said to be Matured Erythrocyte.

Blood...Composition & Functions.........

The Blood Group Systems
Inheritance and Genetics

History of Blood Groups and Blood Transfusions
•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.
He found that mixing blood from two
individuals can lead to blood clumping.
The clumped RBCs can crack and cause
toxic reactions. This can be fatal.

• 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.
•Karl Landsteiner's work made it possible to
determine blood types and thus made the simple
way for blood transfusions to be carried out safely.
For this discovery he was awarded the Nobel
Prize in Physiology or Medicine in 1930.
History of Blood Groups and Blood
Transfusions (Cont.)

What is blood made up of?
An adult human has about 4–6 liters of blood
circulating in the body.
Blood consists of several types of cells floating
around in a fluid called plasma.
The red blood cells (RBCs) contain
haemoglobin, a protein that binds oxygen. RBCs
transport oxygen to, and remove carbon dioxide
from the tissues.
The white blood cells fight infection.
The platelets help the blood to clot, if you get
a wound for example.
The plasma contains salts and various kinds of
proteins.

•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
RBCs called as “agglutinogen” and the antibodies
are in the blood plasma “agglutininn.”
•Individuals have different types and
combinations of these molecules.
•The blood group you belong to depends on what
you have inherited from your parents.
What are the different blood groups?

• There are more than 20 genetically determined
blood group systems known today
• The AB0 and Rhesus (Rh) systems are the
most important ones used for blood transfusions.
• Not all blood groups are compatible with each
other. Mixing incompatible blood groups leads to
blood clumping or agglutination, which is
dangerous for individuals.
What are the different blood groups?

According to the ABO blood
typing system there are four
different kinds of blood types:
A, B, AB or O (null).
ABO blood grouping system

Blood group A
If you belong to the blood
group A, you have A antigens
on the surface of your RBCs
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 RBCs
and A antibodies in your
blood plasma.
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 RBCs and no
A or B antibodies at all in your
blood plasma.
Blood group O
If you belong to the blood group O (null),
you have neither A or B antigens on the
surface of your RBCs but you have both A
and B antibodies in your blood plasma.

Blood
group
antigen on
RBC cells
Antibodies in
serum
Compatible with
blood group
incompatible with blood
group
A A Anti-B A, O B & AB
B B Anti-A B , O A & AB
AB A&B Neither Anti-
A nor Anti-B
A, B, AB, O
{Universal
recipients}
Nil
O Neither
A nor B
Anti-A &
Anti-B
O A, B, AB
{Universal
donors}
Blood Group & Their Interaction

Why group A blood must never be
given to a group B person?
Giving someone blood from the wrong ABO
group could be fatal.
The anti-A antibodies in group B attack group
A cells and vice versa.
• Blood group O negative is a different story.

Well, it gets more complicated here, because there's another antigen to be
considered - the Rh antigen. It is the second most important blood group
system in humans after A-B-O system.
Some of us have it, some of us don't.
If it is present, the blood is Rh+positive, if not it's Rh- negative.
So, for example, some people in group A will have it, and will therefore be
classed as A+ (or A positive).
While the ones that don't, are A- (or A negative).
And so it goes for groups B, AB and O.
The Rhesus (RhD) System

• Rh antigens(D) are transmembrane proteins with loops
exposed at the surface of red blood cells.
• They appear to be used for the transport of carbon dioxide
and/or ammonia across the plasma membrane.
• They are named for the rhesus monkey in which they were
first discovered in 1940.
• 85% of the population is Rh positive, the other 15% of the
population is running around with Rh negative blood.
The Rhesus (RhD) System (Cont.)

According to above blood grouping systems, you can belong to either
of following 8 blood groups:
Do you know which blood group you belong to?

• 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.

Why is an Rh incompatibility so dangerous when ABO
incompatibility is not during pregnancy?
• Most anti-A or anti-B antibodies are of the IgM class
(large molecules) and these do not cross the
placenta.
•In fact, an Rh−/type O mother carrying an
Rh+/type A, B, or AB foetus is resistant to
sensitisation to the Rh antigen.
•Her anti-A and anti-B antibodies destroy any foetal
cells that enter her blood before they can elicit anti-
Rh antibodies in her.

•This phenomenon has led to an effective
preventive measure to avoid Rh sensitisation.
•Shortly after each birth of an Rh+ baby, the
mother is given an injection of anti-Rh
antibodies (or Rhogam).
•These passively acquired antibodies destroy
any foetal cells that got into her circulation
before they can elicit an active immune
response in her.
Rh incompatibility during pregnancy (cont.)

A condition in which fetus or neonate’s red
blood cell (RBC) are destroyed by
Immunoglobulin G (IgG) antibodies
produced by mother.
 "hemolytic" means breaking down of
red blood cells
 "erythroblastosis" refers to making
of immature red blood cells
HEMOLYTIC
DISEASE OF NEWBORN (HDN)

CAUSES OF HDN
Rh incompatibility
- HDN is occured when a mother with Rh-negative
blood becomes pregnant with Rh-positive baby that
inherited from Rh-positive father.
- It occurs when anti-D is stimulated in mother plasma
due to mother ‘s immune response to the antigen D on
fetal’s red blood cells.
- This is due to anti-D is an IgG that capable to cross
placenta and hence delivered to fetal circulation.
- Rh caused HDN is less common but more severe.

• In a first pregnancy, Rh sensitization is not likely. Usually it
only becomes a problem in a future pregnancy with another
Rh positive baby.
• When the next pregnancy occur, the mother's antibodies
cross the placenta then reacts with an RBC antigen to fight
the Rh positive cells in the baby's body that the baby has
inherited from the father, and that is foreign to the mother.
• Hence, the antigen antibody interaction occurs.
RHESUS HEMOLYTIC DISEASE OF
NEWBORN

• Sensitization of baby’s red blood cell (RBC) by mother’s IgG
antibody causes the baby’s RBC to be destroyed.
• These antibody-coated RBCs are removed from fetal circulation
by the macrophages of the spleen and liver.
• The severity of anemia depends on the amount of mother’s
antibody, its specificity, its avidity, and others characteristics.
• Anemia will stimulate bone marrow to produce more RBC
including immature RBC, which is then released to fetus
circulation. This is also known as erythroblastosis fetalis.

HEMOLYTIC
DISEASE OF NEWBORN (HDN)

The ABO Blood Group System
Laboratory Determination
of the ABO System

Several methods for testing the ABO group of an
individual exist. The most common method is:
Serology: This is a direct detection of the ABO
antigens. It is the main method used in blood
transfusion centres and hospital blood banks.
This form of testing involves two components:
a) Antibodies that are specific at detecting a
particular ABO antigen on RBCs.
b) Cells that are of a known ABO group that
are agglutinated by the naturally occurring
antibodies in the person's serum.

People with blood group O
are called "universal
donors" and people with
blood group AB are called
"universal receivers."
Blood transfusions – who can
receive blood from
whom?

Blood
Group
Antigens Antibodies Can give
blood to
Can receive
blood from
AB
A
B
O

Blood
Group
Antigens Antibodies Can give
blood to
Can receive
blood from
AB A and B None AB AB, A, B, O
A A B A and AB A and O
B B A B and AB B and O
O None A and B AB, A, B, O O

WHITE BLOOD CELLS
(Leukocytes)
These cells have an important function in defending the
body against microbes and other foreign materials.
Leukocytes are the largest blood cells and they account
for about 1% of the blood volume. They contain nuclei and some
have granules in their cytoplasm.
Normal WBC count about 5000 to 10,000 cells/mm3
There are two main types
Granulocytes (granular cytoplasm)
Neutrophils, Eosinophils, Basophils
Agranulocytes (lacking granular cytoplasm)
Monocytes, Lymphocytes

Basophil Eosinophil
Neutrophil
Lymphocyte
Monocyte
platelet

Type of WBC’s Description Function
Neutrophils (60-70%)
Nucleus has many
interconnected lobes;
blue granules
Phagocytize and destroy
bacteria; most numerous
WBC
Eosinophils (2-4%)
Nucleus has bilobed nuclei;
red or yellow granules
containing digestive enzymes
Play a role in ending allergic
reactions
Basophils (0.5-1%) Bilobed nuclei hidden by
large purple granules full of
chemical mediators of
inflammation
Function in inflammation
medication; similar in
function to mast cells
White Blood Cells

Type of WBC’s Description Function
Lymphocytes(20-25%)
(B Cells and T Cells)
Dense, purple staining,
round nucleus; little
cytoplasm
the most important cells of
the immune system;
effective in fighting
infectious organisms; act
against a specific foreign
molecule (antigen)
Monocytes (3-8%) Largest leukocyte;
kidney shaped nucleus
Transform into
macrophages; phagocytic
cells
White Blood Cells

Granulocytes (polymorphonuclear leukocytes)
All granulocytes have multilobed nuclei in their cytoplasm. Their
names represent the dyes they take up when stained in the laboratory.
basophils take up basic dyes methylene blue, Eosinophils take up the red
acid dye,(eosin) hence called acidophils or eosinophils; ; and neutrophils
are purple because they take up both dyes.

Basophil
Produces Heparin and Histamines
Stain with basic dye & appeared bluish
purple. 1% of total WBC
Life span one to two days
Diameter 8 to 10 µm
Nucleus-irregular usually bilobed
Functions-
Important in Inflammatory Reaction.
Histamine produce vasodilation.
Number increase in allergic reaction,
leukemis, cancer & decrease in pregnancy,
ovulation, stress.

Eosinophil
• Granules are round & uniformely shaped.
• Get stained with red-orange acidic dye.
• 2% WBC
• Life span one to two days
 Diameter-10 to 20 µm
• Nucleus-fewer lobes usually two
Function- protect body from foreign material, transport
plasmin required in fibrinolysis & wound healing.

Neutrophil
(nucleus has several lobes)
•Active phagocytes
•60% of WBC
•Present in the pus of wounds
•Life span one to two days
Diameter-10 to 20 µm
• appear pale color
Function-
Protect body against microbes & remove
waste material by phagocytosis.

Agranulocytes
The types of leukocyte with a large nucleus
and no granules or small granules in their
cytoplasm are monocytes and lymphocytes and
they make up 25% to 50% of all leukocytes. These
granules have poor staining ability hence are not
visible under the light microscope

Monocyte
(larger cell, Kidney shaped nucleus)
• 3 to 8 % of all WBCs
• Nucleus-oval kidney shaped
• Become macro-phages
• Their number increases in condition of viral or
fungal infection.
Function-
• Phagocytosis & plays important role in
inflammation & immunity.

Lymphocyte
(nucleus is dark and takes up almost whole cell; almost no cytoplasm seen)
• Defense against invaders
• Yield Antibodies
• 30% WBC
• 20 to 25 % of all WBCs
• Nucleus-rounded
Functionally two type-
Activated lymphocytes encounter antigen & provide specific
protective capacity….
•T-lymphocytes- involved in cell-mediated immunity
• B-lymphocytes-primarily responsible for humoral immunity
(relating to antibodies).

PLATELETS
• Thrombocytes are known as platelets.
• Irregular, membrane-enclosed cellular fragments
– about 2 micrometers in diameter (less than one-fourth the size of
an erythrocyte).
• In stained preparations, they exhibit a dark central region.
• Continually produced in the red bone marrow by cells called
megakaryocytes.
• Non-nucleated cells containing granules in cytoplasm.
• Normal count about 2,50,000 to 4,00,000 platelets per cubic mm of
blood.
• Normal life span is about 5-9 days.
Function-
Major role of platelets is in hemostasis as they form platelet plug,
which stop blood loss from damaged blood vessels.

Hemostasis & Blood Coagulation
• Hemostasis is the quick response produced by the body when the
blood vessels are damaged or ruptured to stop bleeding & hence
prevent hemorrhage.
• The process of prevention of blood loss is termed as hemostasis.
• Mechanisms involved-
i. Vascular Spasm
ii. Platelet Plug Formation
iii. Blood Clotting
iv. Growth of fibrous tissue into
blood clot for repair.

1.Vascular Spasm
When arteries or arterioles are damaged, the circularly
arranged smooth muscle in their walls contracts immediately, a
reaction called vascular spasm. When platelets come in contact
with a damaged blood vessel, their surface becomes sticky and
they adhere to the damaged wall. They then release serotonin (5-
hydroxytryptamine),which constricts (narrows) the vessel
reducing blood flow through it. Other chemicals that cause
vasoconstriction e.g. thromboxanes, are released by the damaged
vessel itself.

2. Platelet Plug Formation
Platelet plug formation occur in two steps. The adherent platelets
clump to each other and release other substances, including adenosine
diphosphate(ADP), which attract more platelets to the site. Passing
platelets stick to those already at the damaged vessel and they too release
their chemicals. This is a positive feed back system by which many
platelets rapidly arrive at the site of vascular damage and quickly form a
temporary seal-the platelet plug.

3. Coagulation (blood-clotting)
Normally, blood remains in its liquid form as long as it stays within its
vessels. If it is drawn from the body, however, it thickens and forms a gel.
Eventually, the gel separates from the liquid. The straw-colored liquid,
called serum, is simply blood plasma minus the clotting proteins. The gel is
called a clot. It consists of a network of insoluble protein fibers called fibrin
in which the formed elements of blood are trapped.
The process of gel formation, called clotting or coagulation, is a series
of chemical reactions that culminates in formation of fibrin threads. If
blood clots too easily, the result can be thrombosis clotting in an
undamaged blood vessel. If the blood takes too long to clot, hemorrhage
can occur. Clotting involves several substances known as clotting
(coagulation) factors.

The process of blood coagulation can be divided in three
stages-
1. Formation of prothrombinase
2. Conversion of prothrombin to thrombin
3. Conversion of soluble fibrinogen to insoluble fibrin threads forming clot.
Several of the clotting factor present in blood plasma interact
with each other to form prothrombinase. This formation of
prothrombinase is achieved by two basic pathways…
A. The extrinsic pathway
B. The intrinsic pathway

The extrinsic pathway & intrinsic pathway

A. The extrinsic pathway
The term extrinsic pathway is used because in this pathway utilizes a
protein called ‘tissue factor’ from outside of the blood specifically
from the interstitial compartment..
i. The tissue factor leaks from tissue into the blood and activate
factor VII in the blood in presence of calcium ion.
ii. Activated factor VII in presence of calcium and activates factor X.
iii. Activated factor X combines with factor V in presence of factor
IV(Ca++) to form active enzyme prothrombinase.

B. Intrinsic pathway
it is a complex and slow process the activator for this pathway
are located within the blood and therefore the pathway is called
intrinsic pathway
i. Blood trauma, damage platelet and exposure to collagen fibres
activate factor XII.
ii. Activated factor VII activates factor XI.
iii. Activated factor XI activates factor VII in presence of calcium ions.
iv. Activated factor IX along with factor VII and platelet phospholipids
in presence of calcium and activates factor X.
v. Activated factor X combines with factor V in presence of calcium
ions to form active enzyme prothrombinase.

2. Conversion of Prothrombin to Thrombin
it Prothrombinase formed from the extrinsic & intrinsic
pathways act upon prothrombin & convert it into thrombin in presence
of calcium ion.
Platelets also play important role in conversion of prothrombin to
thrombin. Prothrombin is formed continuously by liver & used
throughout body for blood clotting.
Vitamin-K is an oil soluble vitamin, and is required for production of
prothrombin, factor VII, Factor IX & factor X.
Deficiency may retarded clotting.

3. Blood Clot
Thrombin which is formed form prothrombinase causes
polymerization of fibrinogen molecules into fibrin fibers. Blood cells,
platelets & plasma are entrapped in strengthened fibrin fibers. These
fibrin fibers attached to damaged surface of blood vessels. This
composite is called blood clot.

The process of blood coagulation can be divided in three
stages-
2. Conversion of prothrombin to thrombin
3. Conversion of soluble fibrinogen to insoluble fibtin threads forming clot.

BLOOD DISORDERS
 Anemia – Hb count decrease more than normal.
 Hemophilia – defect in the blood coagulating mechanism
 Thrombocythemia – abnormal small number of platelets
in the circulating blood.
 Hemochromatosis – disorder of iron metabolism
characterized by excessive absorption
 Hodgkin's Disease – marked by chronic enlargement of
the lymph nodes
 Leukemias – Progressive proliferation of abnormal
leukocytes
 Non-Hodgkin's Lymphoma – lymphoma other than
Hodgkin disease

TYPES OF ANEMIA
 Macrocytic anemia: Megaloblastic anemia and
non-megaloblastic macrocyctic anemia. Primary
cause of this sort of anemia is collapse of DNA
synthesis with kept RNA synthesis that occurs
due to the division of the divisional cells.
 Microcytic anemia: Sort of anemia occurs due to
hemoglobin synthesis shortage or collapse.
 Normcytic anemia: Occurs when Hb levels
decreases overall. Size of RBC is often normal.
 Heinz Body anemia: Considered a cell
abnormality that usually occurs in cells under
anemia.

Reticulo endothelial system (RES)
The Reticulo Endothelial System (RES) is a heterogeneous
population of phagocytic cells in systemically fixed tissues that
play an important role in the clearance of particles and soluble
substances in the circulation and tissues.
Reticulo endothelial system a network of cells and tissues
found throughout the body, especially in the blood, general
connective tissue, spleen, liver, lungs, bone marrow, and lymph
nodes. They have both endothelial and reticular attributes and the
ability to take up colloidal dye particles.
Function to remove dead or abnormal cells, tissues, and foreign
substances from blood circulation.

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