introduction, types of immunity, organs of immune system, physiological regulations and functions of immune system.

1. St.ANN’S COLLEGE OF PHARMACY , Chirala
2016-2020
IMMUNOLOGY
Presented by
V.Ragini - 16DU1R0058

3. INTRODUCTION:
• Immunology is the study of host defence mechanism.
• The immune system is a fluid network present inside our body
comprises of many independent types of cells and is designed
to protect us from millions of microbes,toxins and parasites.
• Immunity is the ability of the host to protect itself against
foreign organisms.
Eg:Foreign macromolecules,viruses,worm parasites.
• Protect against pathogens.
• Eliminate damaged or malignant cells.

4. Functions of immune system:
 To protect humans from pathogenic microorganisms.
i. Diseases
ii. Infections
 Eliminate potentially destructive foreign substances from body.
 Distinguishes self from non-self.
Immune system evolves to protect single and multicellular
organisms from danger.

5. Types of immune system:
Immunity against infectious diseases is of different
types:
1. Innate immunity
 Nonspecific immunity
 Specific immunity
2. Acquired immunity
 Cellular immunity
 Hummoral immunity

6. Innate immunity
Depends on
species racial individual
1. Innate or inborn immunity:
It is the immunity which an individual posses by virtue of
his genetic and constitutional make up.
It acts as a first line of defense against
infections,eliminating most potential pathogens before they
establish an overt infection.
Eg: Fowls are resistant to plague,while humans are susceptible.

7. 2. Acquired or Adaptive immunity:
• It can be either natural or artificial immunity.
• It is the resistance developed in the body against any specific foreign
body like bacteria, viruses, toxins, vaccines or transplanted tissues.
• Components are B-cells and T-cells.
• Lymphocytes are responsible for acquired immunity.
Adaptive immunity is further categorized into two types:
a) Hummoral immunity:
It refers to the production of antibody molecules in response to
antigen, mediated by B-cells.
b) Cell-mediated Immunity:
It refers to the production of cytotoxic T-lymphocytes,
macromolecules, activated natural killer cells and cytokines in response to
antigens, mediated by T- lymphocytes.

8. Factors influencing immunity:
• Age
• Nutrition
• Physical stress
• Vaccination
• Health status
• Quality of life

10. Active immunity Passive immunity
• Produced actively by hosts Received passively by the host.
immune system.
• Induced by infection or by No participation by the hosts immune
contact with immunogens. System.
• Affords desired and effective Conferred by introduction of readymade
protection. Antibodies.
• Immunity effective only after a lag Protection transient and less effective
period . Immunity effective immediately.
• Immunological memory present; No immunological memory subseqent
subsequent challenge more effective. administration of antibodies less effective
• Negative phase may occur. No negative phase.
• Not applicable in immunodeficient Applicable in immunodeficient hosts
hosts.
due to immune elimination.

11. Antigen:
Any foreign substance which induces antibody
formation under optimum conditions .
The presence of antigens in the body normally triggers an
immune response.
Eg: Vaccines are examples of antigens in an immunogenic form.

12. Antibodies :
An antibody(Ab) also known as an immunoglobulin(Ig),is a
large Y-shaped protein produced mainly by plasma cells that
is used by the immune system.
Antibodies are secreted by B cells of the adaptive immune
system.

13. Classification according to H chain:
IgM
IgD
IgG
IgA
IgE
Functions :
Neutralization of infectivity.
Paocytosis.
Precipitation.
Antibody dependent cellular cytotoxicity, etc.

14. Organs Of IMMUNE SYSTEM:
 Primary Lymphoid Organs
- Bone marrow and Thymus.
- Maturation Site.
 Secondary Lymphoid Organs
- Spleen, lympnodes
- MALT(mucosal associate lymph tissue)
- ALT(Gut associate lymph tissue )
- Trap angtien, APC lymphocyte proliferation.

15. Physiological regulations:
 The immune system is involved in many aspects of
physiological regulations in the body.
 The immune system interacts intimately with other systems,
such as the endocrine and the nervous system.
 The immune system also plays a crucial role in embryogenesis
(development of embryo),as well as in tissue repair and
regeneration.
Eg:- Hormones, vit-D ,sleep and rest ,
nutrition and diet,repair and regeneration.

16. Refernces:
 Janeway, charles A. 2001.Evolution of the immune system
:past, present and future.
 Retief FP, Cilliers L (1998). The epidemic of Athens, 430-426
BC.South African Medical Journal.
 Plotkin SA((2-0-054_). Vaccines: past, present and future
Nature Medicine.
 Mechnikov, Ilya;translated by F.G . Binnie (1905)
 In Janeway C.A;Travers P;Walport M.& Shlomchik M.2011
Villani AC, Sarkizova S, Hachoen N .
 Specific Disease Types immune Deficiency Foundation.