Antibodies Flashcards
What are antibodies?
These are proteins with specific binding sites synthesised by B cells.
How does the antibody react with the antigen on the surface of the non-self material?
By binding to the antigen.
How many identical binding sites does each antibody have?
Each antibody has two identical binding sites.
What are the binding sites complementary to?
They are complementary to a specific antigen.
Why is there a massive variety of antibodies?
This is because they are proteins.
How many polypeptide chains are antibodies made up of?
4 polypeptide chains
What are the long chains on one pair of polypeptide chains called?
Heavy chains.
What are the chains of the other pair known as?
They are shorted and known as light chains.
What is formed when an antibody fits very precisely onto a specific antigen?
An antigen-antibody complex.
What is different on different antibodies?
The binding site.
What is the binding site known as?
The variable region.
What does each binding site consist of?
A sequence of amino acids that form a specific 3D shape that binds directly to the antigen.
Why is the rest of the antibody known as?
The constant region.
What does the constant region bind to?
Receptors on cells such as those on B cells.
What is the shape of an antibody like?
It is a Y shape.
Do antibodies destroy antigens directly?
No they don’t.
What do antibodies do to the antigen?
They prepare it for destruction.
What are the two ways in which antibodies assist in the destruction of a bacterial cell?
They cause agglutination of the bacterial cells. In this way clumps of bacterial cells are formed, making it easier for the phagocytes to locate them as they are less spread out within the body.
They serve as markers that stimulate phagocytes to engulf the bacterial cells to which they are attached.
What does each antigen induce?
A different B cell to divide.
What does each type of clone produce?
A different antibody.
What are 3 ways in which monoclonal antibodies are used?
Targeting medication to specific cell types by attaching a therapeutic drug to an antibody.
Medical diagnosis.
Pregnancy testing.
What is one type of cell monoclonal antibodies can target?
Cancer cells
How are monoclonal antibodies used in cancer treatment?
Monoclonal antibodies are produced that are specific to the antigens on cancer cells.
These antibodies are given to a patient and attach themselves to the receptors on their cancer cells.
They attach to the surface of their cancer cells and block the chemical signals that stimulate their uncontrolled growth.
Why monoclonal antibody is used to treat breast cancer?
Herceptin
What is the advantage of direct monoclonal antibody therapy?
The antibodies are not toxic and are highly specific.
They have fewer side effects than other therapies.
What is another method that used monoclonal antibodies to treat cancer?
Indirect monoclonal antibody therapy.
How does indirect monoclonal antibody therapy work?
A radioactive or cytotoxic drug is attached to the monoclonal antibody so that when the antibody attaches to cancer cells, it kills them.
What are the advantages of indirect monoclonal antibody therapy?
They can target specific sites so a lower dosage can be used.
They are cheaper.
As a low dosage is used the side effects are reduced.
What are just some of the many infections that monoclonal antibodies can be used to diagnose?
Influenza
Hepatitis
Chlamydia
Why are monoclonal antibodies often used for medical diagnosis?
They are much faster than other methods of diagnosis.
What are monoclonal antibodies important in diagnosing?
Some cancers.
What do pregnancy kits rely on?
They rely on the fact that the placenta produces a hormone called human chorionic gonadotropin (hCG) and that this is found in the mothers urine.
Monoclonal antibodies present o. The test strip are linked to coloured particles. If hCG is present in the urine it binds to the antibodies The hCG-antibody-colour complex moves along the strip until it is trapped by a different type of antibody creating a coloured line.
What are the 3 main ethical issues of using monoclonal antibodies?
Production of monoclonal antibodies involves the use of mice.
There have been some deaths in their treatment of MS
Testing for the safety of new drugs presents certain dangers.
Why are mice used in monoclonal antibody treatment?
They are used to produce both antibodies and tumour cells. If tumour cells are to be created then the mice will have to be directly induced with cancer.
What is needed before patients can use monoclonal antibodies?
The patients mist know of the risks and benefits= informed consent.
What is a problem with B cells that makes producing antibodies hard?
They are short-lived and only divide inside an organism.
What are just some of the many infections that monoclonal antibodies can be used to diagnose?
Influenza
Hepatitis
Chlamydia
Why are monoclonal antibodies often used for medical diagnosis?
They are much faster than other methods of diagnosis.
What are monoclonal antibodies important in diagnosing?
Some cancers.
What do pregnancy kits rely on?
They rely on the fact that the placenta produces a hormone called human chorionic gonadotropin (hCG) and that this is found in the mothers urine.
Monoclonal antibodies present o. The test strip are linked to coloured particles. If hCG is present in the urine it binds to the antibodies The hCG-antibody-colour complex moves along the strip until it is trapped by a different type of antibody creating a coloured line.
What are the 3 main ethical issues of using monoclonal antibodies?
Production of monoclonal antibodies involves the use of mice.
There have been some deaths in their treatment of MS
Testing for the safety of new drugs presents certain dangers.
Why are mice used in monoclonal antibody treatment?
They are used to produce both antibodies and tumour cells. If tumour cells are to be created then the mice will have to be directly induced with cancer.
What is needed before patients can use monoclonal antibodies?
The patients mist know of the risks and benefits= informed consent.
What is a problem with B cells that makes producing antibodies hard?
They are short-lived and only divide inside an organism.
Where in the mouse are the antibodies extracted from when making antibodies?
The spleen
Why are the B cells mixed with cells that divide readily outside the body?
To enable the B cells to divide because normally they don’t divide outside of the organism.
Why is detergent added to the mixture?
To break down the cell-surface membrane of each type is cell and to allow them to fuse together.
What are the fused cells called?
Hybridoma cells.
