The document discusses acquired immunity, which is immunity that develops over time through exposure to pathogens. There are two types of acquired immunity: cellular immunity mediated by T-lymphocytes and humoral immunity mediated by B-lymphocytes. The immune system mounts both a primary and secondary response - the secondary response is faster and stronger due to the presence of memory cells formed during the primary response. Antibodies produced by B-lymphocytes play an important role in the humoral immune response against specific antigens.

1. Acquired
Immunity

2. CONTENT
1.Acquired Immunity
2.Types of Acquired Immunity
3.Primary Response and Secondary Response
4.Antigen
5.Antibody

3. IMMUNITY
 It is the ability of the body to resist the entry different type of pathogens.
e.g. : Bacteria, Viruses and Toxic Substances.
Types Of Immunity
1. Innate
It is present since birth
It is non specific
Represents first line of Defense

4. 2. Acquired
It is the immunity acquired in our day to day life
It is specific
Represents third line of Defense

5. Classification of Acquired
Immunity
1. Cellular Immunity
Due to T-Lymphocyte
2. Humoral Immunity
Due to B-Lymphocyte

6. Development and Processing of
Lymphocytes
1. B-Lymphocytes
It originate and proliferate in Bone marrow
It is called B-Lymphocyte because it was first discover in the
Bursa of Fabricius of the Bird
2. T-Lymphocytes
It originate in Bone Marrow and proliferate in Thymus
Thymosin from thymus gland accelerate the proliferation and
activation of T-lymphocyte in Thymus

7. Types Of T-Lymphocyte
During processing T-Lymphocyte transform
into four type of Cells
1. Helper T-Cell
Also known as CD4 cells.
Because it is present on the surface of Helper T-Cell.
In HIV infected person CD4 cell gets destroyed.
2. Killer T-Cell/Cytotoxic
Also called as CD8 cell.
Because it is present on the surface of Killer T-Cell.
3. Suppressor
4. Memory Cell

8. Types Of B-Lymphocyte
During processing B-Lymphocyte transform
into two type of Cells
1. Plasma Cell 2. Memory Cell

9. Antigen
Antigens are Substances which induces
Specific Immunity Reaction in body.
Antigen may be Lipoprotein, Glycoprotein,
Nucleoprotein
Two type :
1. Self Antigen
Present on body own cells.
e.g. : “A” Antigen, “B” Antigen in RBC membrane.
2. Non-Self/Foreign Antigen
Enter the body from Outside.

10. Antigen Presenting Cells (A.P.C.)
It is a special type of
cell which induces
the release of
antigenic material
from the invading
organism and later
present this material
to Helper T-cells.

11. Antibody
It is protein produced by “B” Lymphocyte in the
response to an antigen.
Antibody are formed by two pair of chain
1 pair for Heavy, 1 pair for Light
Which is read as H2L2.
Constant Region
Amino acid present in this region are similar in Number and
Arrangement.

12. Variable Region
Amino acid present in
this region are dissimilar
in Number and
Arrangement.
It enable to recognize
the specific antigen.

13. Types of Immunoglobulin
IgG
IgA
IgM
IgD
IgE

14. BIBLIOGRAPHY
1. GUYTON AND HALL
2. SEMBULINGAM