Antibodies and painkillers

• Antibodies are proteins produced by white blood cells to help fight infections
• Each antibody is specific to a particular pathogen
• Antibodies recognise pathogens by binding to antigens (proteins on the pathogens surface)
• Antibodies mark pathogens for destruction by other white blood cells
• Antibodies neutralise toxins produced by bacteria
• Antibodies prevent viruses from entering cells
• Antibodies are specific to one type of antigen meaning they fit using the lock and key method
• When a pathogen enters the body, white blood cells (lymphocytes) detect its antigens
• The immune system produces specific antibodies that attach to the antigens
• The antibodies:

  • Clump the pathogens together so white blood cells can destroy them
  • Neutralise toxins released by bacteria
  • Block viruses from entering cells
• After fighting an infection, the body keeps memory cells that remember how to make the right antibody
• If the same pathogen enters again, antibodies are produced much faster, giving immunity
• Antibodies provide long-term immunity by allowing the immune system to respond faster on re-infection
• Painkillers are drugs that relieve symptoms of disease but do not kill pathogens
• Painkillers help to reduce pain, fever and inflammation caused by infections
• Painkiller: Aspirin

  How it works: Blocks pain signals and reduces inflammation

  Common uses: Headaches, fever, joint pain
• Painkiller: Paracetamol

  How it works: Reduces fever and blocks pain messages

  Common uses: Flu, colds, mild pain
• Painkiller: Ibuprofen

  How it works: Anti-inflammatory; reduces swelling and pain

  Common uses: Muscle pain, arthritis, fever
• Painkillers: relieve symptoms but do not kill pathogens
• Antibiotics: kill or stop the growth of bacteria but do not work on viruses
• Why don’t antibiotics work on viruses?

  Viruses live inside host cells so antibiotics cannot reach them without damaging human cells. Viruses do not have cell walls or metabolism that antibiotics can target.