Transcript Monoclonal antibodies

Monoclonal Antibodies
• Aims:
• Must be able to define the term monoclonal
antibody.
• Should be able to outline the possible uses of
monoclonal antibodies.
• Could be able to describe the process by which
monoclonal antibodies are produced.
Monoclonal Antibodies
•
A monoclonal antibody is an artificially produced antibody that
neutralises only one specific protein (antigen).
– Monoclonal antibodies produced by stimulating the production of Bcells in mice injected with the antigen.
– These B-cells produce an antibody against the antigen.
– B-cells can be isolated and made to fuse with immortal tumor cells.
They can then be cultured indefinitely in a suitable growing medium.
– Monoclonal antibodies are useful for 3 reasons:
• They are totally uniform (i.e. clones).
• They can be produced in large quantities.
• They are highly specific.
Making Monoclonal Antibodies
A mouse is injected with
a foreign protein
(antigen).
The mouse’s B-cells produce an
antibody to recognize the
antigen.
A few days later,
antibody-producing Bcells are taken from the
mouse’s spleen.
The mouse cells and
tumor cells are mixed
together in
suspension.
The mixture of cells is placed
in a selective medium that
allows only hybrid cells to
grow.
Pure tumor cells are
harvested from
culture
Some of the mouse cells
fuse with tumor cells to
Hybridoma cells make hybrid cells called
hybridomas.
Mouse cell and
tumor cell fusing
Unfused cell
Hybridomas are screened for
antibody production. They are
then cultured to produce large
numbers of monoclonal
antibodies.
Monoclonal Antibody Therapy
•
Monoclonal antibodies have many therapeutic uses:
– Neutralizing endotoxins produced by bacteria in blood infections.
– Preventing organ rejection, e.g. in kidney transplants, by interfering with T cell
activity.
– Treatment of some autoimmune disorders such as rheumatoid arthritis and
allergic asthma.
– Immunodetection and immunotherapy of cancer. Newer methods specifically
target tumor cells, shrinking solid tumors - no harmful side effects.
– Inhibition of platelet clumping to prevent reclogging of coronary arteries after
angioplasty.
Diagnostic Uses
• Monoclonal antibodies have many diagnostic uses:
– Detecting the presence of pathogens such as
Chlamidia and streptococcal bacteria, distinguishing
between Herpesvirus I and II, and diagnosing AIDS.
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Measuring protein, toxin, or drug levels in serum.
Blood and tissue typing.
Detection of antibiotic residues in milk.
Detecting pregnancy.
Activity
• Complete the activities on page 159 in
Biozone book.