Immune response

• All cells have unique proteins on their surface called antigens. The immune system will recognise any cells as 'foreign' if their antigens are different to the ones on body cells. 'Foreign' antigens stimulate an immune response by the body
• Primary response


  1. Lymphocyte recognises 'foreign'
  2. Clones differentiate. Most develop to form short lived plasma cells
  3. Plasma cells produce antibodies that will destroy cells carrying the specific 'foreign' antigen
  4. Some clones develop into long lasting memory cells
• Secondary response


  1. Memory cells are long lasting and if they come across the same specific antigen again they stimulate an immune response
  2. Large numbers of plasma cells develop producing a large concentration of antibodies very quickly
  3. More memory cells produced. This 'boosts' immunity