Download BLOCK F – Krizia,Kevin,Synnove – Production of Antibodies

Kevin Chang
Krizia Carungcong
Synnøve Eriksen
PRODUCTION OF ANTIBODIES
What are antibodies?
- It is a protein that binds to antigens
o Antigens are chemicals that stimulate immune responses to foreign
proteins and molecules on the surface of pathogens.
- Our body can produce a vast array of different antibodies, each one binds to a
specific antigen
Outcomes of binding antibodies to antigens:
- Makes pathogens more recognizable to phagocytes, so they can easily be engulfed
- Prevents viruses from docking to host cells so that they cannot be taken up by
host cells
- Causes agglutination (sticking together) of pathogens so that they are prevented
from entering cells and are easier for phagocytes to ingest.
Production of antibodies:
Where?
- In lymphocytes (white blood cells)
o B-lymphocytes  differentiate in the bone marrow
o T-lymphocytes  differentiate in the thymus
The Process:
1. A B Cell is trigged when it encounters its matching antigen.
2. The B-Cell engulfs the antigen and digests it.
3. Then, it displays antigen fragments bound to its unique MHC molecules.
4. This combination of antigen and MHC attracts the help of a mature, matching Helper
T Cell.
5. Cytokines secreted by the Helper T cell help the B cell to multiply and mature into
antibody producing plasma cells.
6. Antibodies then lock onto
matching antigens.
7. Antibodies are made up of white
blood cells, called B lymphocytes
or B Cells. Each B Cell carries a
different membrane-bound
antibody molecule on its surface
that serves as a receptor for
recognizing a specific antigen.
When antigen binds to this
receptor, the B cell is stimulated to
divide and to secrete large
amounts of the same antibody in a
soluble form.
Clonal selection:
1. When a pathogen has been
engulfed by a phagocyte, antigens from ruined pathogen are displayed on the
surface of the phagocyte, bound to a membrane called MHC protein.
2. A receptor on the surface of a specific T-lymphocyte binds to the displayed
antigen and is activated
3. Plasma B-lymphocytes secrete antibodies specific to the invading pathogen
4. Memory B-lymphocytes remain after the infection and will be involved in
producing a more rapid response if the same pathogen infects the body again.