Antibody Structuer Flashcards
What are antibodies
Proteins which bind to antigens to form an antigen antibody complex
They are produced by b lymphocytes
What is the structure of antibodies
Antibodies are proteins made up of 4 polypeptide chains, the quaternary structure
2 heavy and 2 light chains
Each chain has a variable and constant region connected by disulphide bridges
What are the constant regions
The regions that allow them to bind to receptors on immune system cells
What are the variable regions
The antigen binding sites, they have a unique tertiary structure which is complementary to an antigen
What is agglutination
Antibodies bind to antigens on pathogens which causes them to clump together, these clumps are then destroyed by phagocytosis. This makes it easier to engulf more pathogens at one time
What is neutralising toxins
Some antibodies work by neutralising toxins released by pathogens
What do the spike proteins on viruses do
Viruses have spike proteins on their surface which recognise and bind to receptors on the surface of the host cell which allow them to enter the cell. Antibodies can bind to these on viruses and stop them from attaching to their host cell
What is the memory cell function
Why we generally catch a disease once
The pathogens creating these diseases are of a single type and have the same antigen, so are rapidly identified by the memory cells of the secondary immune response is triggered which quickly wipes out the virus
What is antigenic variation
When pathogens form different strains caused by mutations in genetic material, which often have different antigens. So if u are infected again, the memory cells will not recognise the antigen so wont be activated, the antibodies made last time wont be complimentary so the body has to start again with the primary response so you still get symptoms
