vaccines

• What is variolation?

  Deliberate exposure to a controlled amount of an infectious agent to induce immunity.
• Which infectious agent was primarily used in variolation?

  Smallpox (variola).
• What does attenuation refer to in vaccine development?

  Preparing weakened versions of infectious agents.
• How did Pasteur use the scientific method in vaccine testing?

  By using animal models of infection.
• What are the problems associated with intracellular pathogens?

  Growing large amounts of pathogens and testing vaccine efficacy.
• What is the first step in virus attenuation as exemplified by the Sabin Polio Vaccine?

  Isolating and culturing the pathogenic virus on host cells.
• What happens to the virus during the attenuation process?

  It spontaneously mutates and grows on monkey cells.
• Why can the attenuated virus be used as a vaccine?

  It cannot grow on human cells.
• What are killed vaccines?

  Vaccines that use chemicals or heat to kill the organism.
• How do killed vaccines induce immunity?

  By using antigens from the killed organism.
• What is an example of a killed vaccine?

  Salk Polio Vaccine.
• What are subunit vaccines?

  Vaccines that isolate antigens from cultivated viruses or bacteria.
• How do antibodies protect against infection in subunit vaccines?

  By targeting the isolated antigens.
• What are disease-causing parts of pathogens called?

  Toxins.
• What did Paul Ehrlich propose in 1908 regarding antibodies?

  Antibodies produced against toxoids could protect against toxins.
• What theory did the work of Emil von Behring and Paul Ehrlich lead to?

  The lock and key specificity theory for antibodies and antigens.
• What are the phases of adaptive immune responses?

  • Immunological memory exists in humoral and cell-mediated immune compartments.
  • Memory lymphocytes are long-lived, have increased frequency, rapid proliferation, and produce more and higher affinity antibodies.
  • B cells and T cells (CD4 & CD8) have better effector functions.

  
• What is the difference between memory and naïve lymphocytes?

  Memory lymphocytes are long-lived and have better effector functions.
• What are the characteristics of memory B cells?

  They are long-lived, have increased frequency, and produce more antibodies.
• What are the characteristics of CD4 and CD8 T cells?

  They are long-lived, have increased frequency, and better effector functions.
• What is the role of immune activation?

  To initiate and enhance the immune response against pathogens.

  
• How do vaccines work in relation to toxins?

  They prepare inactivated forms of toxins called toxoids to protect against disease.
• What is adaptive immunity?

  A specific immune response that develops over time and provides long-lasting protection.
• What is immunological memory?

  The ability of the immune system to remember past infections and respond more effectively upon re-exposure.

  
• What is the significance of high-affinity antibodies?


  They provide better protection against pathogens.
• What is the role of IgG and IgA antibodies?


  They have better effector functions in the immune response.
• What is the difference between memory and naïve B cells?

  Memory B cells have a lower activation threshold and better effector functions.
• What is the significance of rapid proliferation in memory lymphocytes?


  It allows for a quicker immune response upon re-exposure to the pathogen.

  
• How do memory T cells differ from naïve T cells?

  Memory T cells have a lower activation threshold and better effector functions.
• What is the role of immune activation in the immune response?

  To enhance the body's ability to fight off infections.