This document discusses the different types of immunity. It begins by defining immunity and describing the innate immunity system, which includes anatomical barriers like skin and mucous membranes, physiological barriers like low pH levels, and biological barriers like white blood cells. The document then explains acquired immunity, noting it is antigen specific, diverse, leads to immunological memory, and involves self/non-self recognition. Acquired immunity is divided into active immunity, which occurs from natural exposure or vaccination, and passive immunity, which results from transfer of antibodies or immune cells from another individual. Both active and passive immunity can be naturally acquired or artificially acquired.

1. 1
TYPES OF IMMUNITY
By,
Rajamehala M
Assistant Professor,
Vivekanandha College of Engineering for Women,
Tiruchengode

2. outline
2
Immunity
1.introduction
2.types of immunity
innate immunity
acquired immunity
1. natural immunity
2. artificial immunity

3. IMMUNITY
3
 The term immunity refers to the resistance exhibited
by the host towards infection caused by micro
organisms and their products(toxins).
 This is based on the property of self and non self
recognition. That means immunity is carried out by
the process of recognition and disposal of non self or
materials that enter the body.
 Immune response is the reaction of the body against
any foreign antigen.
 Protection against infection disease is only a part of it.

9. Types of immunity
Immunity
Innate immunity Acquired immunity
Anatomic Phagocytic Blood
al barriers barriers proteins
Cytokines Passive
immunity
Active
immunity
Naturally
acquired
Artificially
acquired
Naturally
acquired
Artificially
acquired

10. Innate immunity
 It is also called natural or native immunity, consist of
mechanisms that exist before infection and are capable of
rapid responses to microbes.
 It is comprised of four types of defense barriers-
1) Anatomical barriers
2) Phagocytic barriers
3) Blood proteinsand
4) Cytokines.

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• It is comes because of genetic and constitutional
make up.
• It has no relation ship with previous bacterial
infection and immunisation.
• It acts as first line of deffence agenest infections,
micro organisms, their products before they cause
disease.
Type Mechanism
 Skin
 Mucous membrane
 Temperature
 Low pH
3)Phagocytic barriers
NK cells)
4)Inflammatory barriers
1)Anatomical barriers
Mechanical barriersretards entry of
microbes.
Acidic environment (pH 3-5) retards
growth of microbes.
Mucous entrapsforeign microorganism.
2) Physiologic barriers
Bodytemperatureand fever response
inhibits growth of somepathogens.
Acidic pH of stomach (pH 2)kills most
ingested microorganism.
Ingest and destroysmicrobes by
(Neutrophils, Macrophages and endocytosis and phagocytosis)
Tissuedamage and infection induce
leakage of vascular fluid, containing serum
protein with antibacterial activity.

15. Skin
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16. Mucous membrane
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The respiratory , GIT etc. lined by
mucous membrane
It blocks the micro organisms
because of its sticky nature.
coughing and sneezing
the mechanical actions may help in
driving out the foreign particles that enter
the digestive and respiratory

17. Physiological and chemical barriers
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 Human milk: this is very rich in anti bacterial
substances. Ex:IgA, lacto feritin, neuraminic acid
etc. they fight against
E.coli and stephylococci.
 Secrition of the digestiv tract: stomach as microbicidal
effect. This is due to the presence of Hcl in the gastric
juice. This Hcl is secreted by oxyntic cell lining
stomach.
 Nasal secretion and saliva:
 Inter ferons:
 Compliment:

18. Biological barriers
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• These includes mono nuclear phagocytic system
which was originally called reticulo endothelial
system(RES).
• Biological barriers include endocytosis.
• Endocytosis: it is the process in which cells absorb
materials from the out side of the environment by
engulfing them with their cell membrane.
Types: the absorbing of material from the out
side of the environment of cell is commonly divided
in to 2 types.
1.Phagocytosis.
2.pinocytosis

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20.  It is of three types-
1) Species Immunity
2) Racial Immunity
3) Individual Immunity
 Species immunity is the total immunity
shown by all members of a species against
pathogen; e.g. birds immune to tetanus.
 Racial immunity is that in which various races
show marked difference in their resistance to
certain infectious disease.
 Individual immunity is very specific for each and
every individual despite having same racial
background and opportunity for exposure.

23. Acquired immunity
Acquired or adaptive immunity is the immunity that is
developed by the host in its body after exposure to suitable
antigen or after transfer of antibodies or lymphocyte from an
immunedonor.
Characteristics of Acquired Immunity
1. Antigenic Specificity
2. Diversity
3. Immunologic memory
4. Self/non-self recognition

28. Types of Acquired Immunity
Acquired Immunity is of two types- active and passive
immunity.
1. Active immunity
It is induced by natural exposure to a pathogen or by
vaccination.
It can be categorized into two types-
Naturally acquired and Artificially acquired active immunity.
2. Passive immunity
Passive immunity is achieve by transfer of immune products,
such as antibody or sensitized T-cells, from an immune
individual to non immune one.
It is of two types- Naturally acquired and Artificially
acquired passive immunity

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30. Mechanism of active immunity
• Body’s immune system provide protection by
synthesizing antibodies or immunoglobulins in
response to anantigen.
• Primary immune response takes place when the
host is attacked by certain microbes for first time. The
antibodies start to generate after certain period as the
binding of an antigen with its particular antibody is
veryspecific.
• Secondary immune response occurs when an
individual is being attacked by the same antigen
subsequently. It is a rapidprocess.
• Acquired active immune response takes two distinct
forms- humoral and cell mediated response.