Immune Response and Currently
Used Immunizing Agents under
PRESENTED BY:- DR.NAVIN KUMAR
What is immunity?
Immunity involves the antigen-
From the Latin word “immunis”—
Immunity involves the antigen-
The immune system produces
antibodies or cells that can deactivate
The immune system recognizes,
attacks, destroys, and remembers each
pathogen that enters the body.
It does this by making specialized cells
and antibodies that render the
For each type of pathogen, the immune
system produces cells that are specific
for that particular pathogen
Functions of the Immune System
Immune System has 3 main
– Protect the body from pathogens
– Remove dead or damaged tissue and
– Recognize and remove abnormal cells
that have abnormal cell growth and
development (i.e. cancer cells)
The Immune System - includes all
parts of the body that help in the
recognition and destruction of
- White blood cells, phagocytes and
lymphocytes, bone marrow, lymph
nodes, tonsils, thymus, and spleen
are all part of the immune system.
Resistance developed in response to
stimulus by an antigen (infecting
agent or vaccine) and is
characterized by the production of
antibodies by the host.
Active Immunity occurs when one makes
his/her own antibodies.
- This type of immunity is long term.
Getting the disease : If one get an
infectious disease (like Chicken
Pox), often times, that stimulates the
production of MEMORY cells which
are then stored to prevent the
infection in the future.
A. HUMORAL IMMUNITY
This type of immunity is due to circulating Abs
(Gamma-globulin's also called immunoglobulins)
On stimulation, B-lymphocytes divide and its
daughter cells are transformed into plasma-
The latter secrete the Abs into the circulation.
An antibody is a protein produced in
response to an antigen.
5 Types of Antibodies
Immunoglobulin G (IgG)—in plasma
and tissue fluids; effective against
virus, bacteria, & toxins; activate
complement; babies get from mother
through cord lasts 6 months to 1 yr
Immunoglobulin A (IgA)—in exocrine
gland secretions (sweat glands);
breast milk, tears, nasal fluid, bile,
Immunoglobulin M (IgM)—develops in
response to bacteria
Immunoglobulin D (IgD)—found on
surfaces of B-cells; important to B-
Immunoglobulin E (IgE)—in exocrine
secretions along with IgA;
ASSOCIATED WITH ALLERGIC
B. CELLULAR IMMUNITY
Another way of establishing host resistance is through
These cells synthesize and release pharmacologically
active substances ("lymphokines") which can kill
cell carrying foreign Ags.
T-lymphocytes also act against the invader by
stimulation of macrophages.
This activity of the immune system is known as cell
mediated immunity. The peak of activity occurs around
the tenth day.
CELL MEDIATED IMMUNITY
In cell mediated immunity, the
t-cells attach to foreign
antigen cells and interact
directly by cell to cell contact
Immunity conferred by an antibody
produced in another host.
It may be acquired naturally or
artificially (through an antibody-
While our immune system was developing,
We were protected by immune defenses
These antibodies traveled across the
placenta from the maternal blood to the fetal
Passive Immunity occurs when the antibodies
come from some other source. This type of
immunity is of short term.
Milk from a mother's
The baby is acquiring
These antibodies will
only last several weeks.
Vaccine: Vaccine is an immuno-biological substance
designed to produce specific protection against a given
Toxoid: Exotoxins produced by some bacteria are
detoxified and used in the preparation of vaccine.
Immuno globulin: sterile solution containing antibodies
from human blood.
Antitoxin: solution of antibodies derived from the serum
of non-human sources.
Vaccination and Immunization
Vaccination and vaccine derived from
vaccinia, the virus once used as smallpox
Thus, vaccination originally meant
inoculation with vaccinia virus to render a
person immune to smallpox.
Immunization: process of inducing or
providing immunity by administering an
Active: production of an antibody in
response to the administration of a vaccine
Passive: temporary immunity by the
administration of preformed antibodies or
Agents used include: Ig’s and antitoxins
Vaccination: A vaccination is an injection
of a weakened form of the actual antigen that
causes the disease.
-The injection is too weak to make one
sick, but his B lymphocytes will recognize the
antigen and react as if it were the "real
- Thus, he produce MEMORY cells for long
Live attenuated (avirulent) vaccines
Virulent pathogenic organisms are treated to
become attenuated and avirulent but antigenic.
They have lost their capacity to induce full-blown
disease but retain their immunogenicity.
Live attenuated vaccines should not be
administered to persons with suppressed immune
response due to:
– Leukemia and lymphoma AND other malignancies.
– Receiving corticosteroids and anti-metabolic agents
Inactivated (killed) vaccines
Organisms are killed or inactivated
by heat or chemicals but remain
They are usually safe but less
effective than live attenuated
The only absolute contraindication to
their administration is a severe local
or general reaction to a previous
Polysaccharide and polypeptide (cellular
They are prepared from extracted cellular
fractions for e.g.
Meningococcal vaccine from the
polysaccharide antigen of the cell wall
Pneumococcal vaccine from the
polysaccharide contained in the capsule of
Hepatitis B polypeptide vaccine.
Their efficacy and safety appear to be high.
Surface antigen (recombinant)
• Are those in which genes for desired antigens are inserted
into a vector, usually a virus, that has a very low virulence.
• The vector expressing the antigen may be used as the
vaccine, or the antigen may be purified and injected as a
• The only recombinant vaccine currently in use in humans is
the Hepatitis B Virus (HBV) vaccine, which is a recombinant
• Hepatitis B surface antigen is produced from a gene
transfected into yeast cells and purified for injection as a
The specific reactivity induced in a host
by an stimulus is known as the immune
It has a wider scope and includes
reactions against any ANTIGEN, living
It may lead to consequences that are
beneficial, indifferent or injurious to the
PRIMARY RESPONSE: When an Ag is
administered for the first time to a host (never
exposed), there is a latent period of induction of
3-10 days before Ab appears in the blood.
Ab- IgM apears 1st
, its titre rises
steadily in next 2-3 days, reaches a
peak level then declines as fast as it
Meanwhile, if the ANTIGENIC
stimulus was sufficient, IgG Ab
appears in few days.
Reaches a peak in 7-10 days then
gradually falls over a period of weeks
Shorter latent period
Production of Ab is more rapid
Produces both IgG and IgM
Ab more abundant
Ab response maintained at higher levels for a
Ab elicited tends to have a greater capacity to
bind to the antigen
Collaboration of B-cell and T-cell is essential to
initiate a secondary response.
WHO launched a global immunization
PROGRAMME OF IMMUNIZATION” in
May,1974 to protect all children
against six vaccine-preventable
DIPHTHERIA, WOOPING COUGH,
TETANUS, POLIO, TUBERCULOSIS
EPI launched in INDIA in January,
Currently Used Immunizing agents In
National Immunization Schedules as
PROGRAMME in india.
Launched on 19th
Aimed to achieve Universal
immunization coverage of the eligible
population by 1990.
FACTSHEET OF OPV IN INDIA
Cases in 2011: 1 (last case 13 January 2011)
Cases in 2010: 43
Cases in 2009: 756
Cases in 1991: 5,895
Cases in 1985: 22,570
Last wild poliovirus type 1 (WPV1) case: 13 January
2011, Howrah, West Bengal
Last wild poliovirus type 2(WPV2) case: October1999,
Aligarh, Uttar Pradesh
Last wild poliovirus type 3 (WPV3) case: 22 October
2010, Pakur, Jharkhand
Bacterial Meningitis kills several in Developing
Haemophilus influenzae type b (Hib):
30% -50% of bacterial meningitis
25- 35% of bacterial meningitis
25 - 35% of bacterial meningitis
(except during epidemics)
Reduces incidence of Hib MENINGITIS,
PNEUMONIA and Nasopharyngeal colonization
by Hib bacteria in infants.
Capsular polysaccharide conjugated with
protein carrier .
Contraindicated in less than 6 weeks of age.
Vaccine schedule: 6th
Children over 5 years old usually do not need
INDIA: Tamil Nadu will be the 1st
to vaccinate all Newborns in the
PENTAVALENT vaccine: combines
with DPT, Hepatitis B and Hib
Hepatitis B vaccine
Is a very safe vaccine
Infants born to HBsAg-positive
mothers should receive the vaccine
and HBIG within 12hr of birth.
Inactivated whole organism vaccine
DTP or Acellular vaccine DTaP
Acellular type has less side effects
Side effects :
Mild Problems (Common):
Fever, Redness, swelling, Soreness
(1 in 4)
Fussiness ,Tiredness or poor appetite
and Vomiting (1 in 50)
There is evidence that BCG provides
appreciable protection against
tuberculosis meningitis (50-80%) and
Local lesion, papule, 2 weeks after
Small abscess might develop, 4-6
At 6 weeks (crust, detaches, ulcerates)
then a scar (typically round and
slightly depressed) remains.
• Live attenuated vaccine
• Subcutaneous injection
• Side effects :
Mild Problems :
1. Mild rash (1 in 20)
2. Swelling of glands in the cheeks
or neck (rare) If these problems occur,
it is usually within 7-12 days after the
They occur less often after the
PARK’S TEXTBOOK OF PREVENTIVE AND SOCIAL
TEXTBOOK OF MICROBIOLOGY by Ananthanarayan and
MOHFW (GOVT.OF INDIA).
WHO vaccine-preventable diseases: monitoring system
2012 global summary.
WHO | Poliomyelitis