Immunity

• What are the two types of immunity?


  • Active immunity: production of antibodies in response to antigens.
  • Passive immunity: introduction of antibodies from another source.
• What are the subtypes of immunity?


  • Natural active: exposure to antigens.
  • Natural passive: maternal antibodies.
  • Active artificial: vaccinations.
  • Passive artificial: injected antibodies.
• What is the purpose of vaccines?


  • Introduce a pathogen to produce an immune response.
  • Create memory B cells for rapid secondary response.
• What factors affect the success of a vaccination program?

  • Cost of the vaccine
  • Severity of side effects
  • Ease of production, transportation, and administration
  • Number of people needed for herd immunity
• What is herd immunity?


  Protection of unvaccinated individuals when enough people are vaccinated.
• Why might vaccines not always prevent disease outbreaks?

  Pathogen antigens can change, removing immunity.
• What ethical considerations are associated with vaccines?

  • Animal testing for production and testing
  • Balancing risks and benefits
  • Human toxicity testing
  • Cost of vaccinations
  • Compulsory vs. voluntary vaccinations
• What are monoclonal antibodies?


  • Clones of a single type of antibody.
  • Medically useful for therapy, diagnosis, and pregnancy testing.
• How are monoclonal antibodies used in direct therapy?


  • Target and destroy cancerous cells.
  • Example: Herceptin targets breast cancer cells.
• How are monoclonal antibodies used in indirect therapy?


  • Drugs attached to antibodies direct them to specific cells.
• How are monoclonal antibodies used in diagnosis?


  • Target specific antigens to measure their levels in the body.
• How are monoclonal antibodies used in pregnancy testing?


  • Specific to the hormone human chorionic gonadotrophin.
• What is the structure of HIV?


  A lipid envelope with attachment proteins and a protein capsid containing RNA and reverse transcriptase.
• How does HIV replicate inside a host cell?


  HIV binds to CD4, fuses with the membrane, and converts RNA to DNA using reverse transcriptase.
• What is the purpose of the ELISA test in relation to HIV?


  To detect the presence and quantity of HIV antigens.
• Why are antibiotics ineffective against HIV?


  Antibiotics target bacterial cell walls, which viruses lack.
• What type of drugs are used to treat HIV?


  Antiretroviral drugs