3.2.4 - Antibody Structure

Wednesday 24th January ‘24

Proteins with specific binding sites, synthesised by B cells. Bind with antigens to form antigen-antibody complexes.

How do they lead to destruction?

• Agglutination - cause pathogens to clump together so it is easier for phagocytosis to occur as they are less spread out.

• Neutralising toxins (in bacterial infections)

• Virus receptors - preventing them being able to bind to receptors on host cells.

Why do some diseases cause us to become ill once and some numerous times?

• Memory cells explain why we generally are only ill with chicken pox or measles once.

• Some pathogens can form different strains (caused by mutations in genetic material) which often have different antigens - antigenic variation. Uncomplementary antibodies (produced by memory cells) so go back to the start of the immune response.

1. Mouse vaccinated with pathogen and produces lymphocytes.

2. Lymphocytes fuse with tumour cells which causes them to diide (hybridoma cells). These all make the same antibody.