antigens

• antigens are molecules that generate an immune response
• pathogens are microorganisms that cause disease
• cancerous cells have an abnormal antigens on the surface
• toxins activate the immune system and pathogens release them
• cells from other individuals have different antigens on their surface which can trigger an immune response
• antigenic variation is when the pathogens change their surface antigens
• antigenic variation meas that the memory cells wont recognise the antigen and the primary response will have to take place
• antigenic variation makes it difficult to develop vaccines agains some pathogens
• monoclonal antibodies are antibodies that are produces from a single group of identical plasma cells
• ELISA allows you to see if a patient has antibodies to a certain antigens to a certain antibody
• ELIZA tests can can be used for medical diagnosis to test for pathogenic infections
• direct ELIZA:

  • patient antigens are bound to the inside of the well
  • a detection antibody attached to an enzyme that is complementary to the antigen is added
  • the well is washed out
  • substrate solution is added
• indirect ELISA:

  • antigen is bound to the bottom of the well
  • patients blood is added and if it has antibodies for that antigen they bind to the antigen
  • wash out the well
  • secondary antibody attaches to the specific antibody that carrie s a specific enzyme
  • a solution is added to the well that contains a substrate