Microbiology: Applications of the Immune Response – Guided Study Notes

Q1. Define the term immunization vs. immunotherapy.

Key Terms

• Immunization: The process by which an individual's immune system is fortified against an agent (usually a pathogen) through exposure to an antigen, often via vaccination.

• Immunotherapy: The use of immune system components (such as antibodies or immune cells) or modulators to treat disease, often cancer or autoimmune disorders.

Q2. Distinguish between natural vs. artificial immunity and active vs. passive immunity. Using these terms, define which type of immunity each of the following terms would fall under: illness, antiserum, breast feeding, vaccine.

Key Terms

• Natural Immunity: Immunity acquired through natural biological processes (e.g., infection, maternal transfer).

• Artificial Immunity: Immunity acquired through medical intervention (e.g., vaccination, antibody therapy).

• Active Immunity: Immunity resulting from the body's own immune response to an antigen.

• Passive Immunity: Immunity acquired by receiving antibodies from another source.

Q3. Define immunoglobulin. What are the five types of immunoglobulins and which ones are found in blood and mucosal sites?

Key Terms

• Immunoglobulin (Ig): A type of protein produced by B cells that functions as an antibody.

• Types of Immunoglobulins: IgG, IgM, IgA, IgD, IgE

Q4. Define a vaccine. Describe how they benefit both the immunized individual and those who are not able to be vaccinated. How does the term herd immunity fit into this concept?

Key Terms

• Vaccine: A preparation that stimulates the immune system to develop immunity to a specific pathogen.

• Herd Immunity: When a high percentage of the population is immune, reducing the spread of disease and protecting those who cannot be vaccinated.

Q5. For attenuated (live) and inactivated (dead) vaccines, describe the pros and cons of each and list and briefly describe the different types of inactivated vaccines that exist.

Key Terms

• Attenuated Vaccine: Contains live, weakened pathogens.

• Inactivated Vaccine: Contains killed pathogens or components.

Q6. Explain your understanding of the importance of vaccines in society despite the risks that are associated with them. What are some reasons why people have chosen to not get themselves or their kids vaccinated?

Key Terms

• Risk-Benefit Analysis: Weighing the benefits of vaccination against potential risks.

• Vaccine Hesitancy: Reluctance or refusal to vaccinate despite availability.

Q7. Explain the use of antibodies as an important tool in developing diagnostic tests in the way of immunoassays.

Key Terms

• Immunoassay: A laboratory technique that uses antibodies to detect or quantify substances.

• Antibody: A protein that specifically binds to an antigen.

Q8. Define the terms seropositive, seronegative and seroconversion. How do these terms relate to disease state?

Key Terms

• Seropositive: Presence of specific antibodies in the blood, indicating exposure or infection.

• Seronegative: Absence of specific antibodies in the blood.

• Seroconversion: The change from seronegative to seropositive status.

Q9. For monoclonal and polyclonal, briefly define these types of antibodies, describe how they are produced, and finally describe their main pros and cons, if any.

Key Terms

• Monoclonal Antibody: Produced by a single clone of cells; specific to one epitope.

• Polyclonal Antibody: Produced by multiple clones; recognizes multiple epitopes.

Q10. Distinguish between direct and indirect tests. Summarize the major components and strategies of each type of test and briefly describe the basic setup for a generic direct or indirect test.

Key Terms

• Direct Test: Detects the presence of an antigen using a labeled antibody.

• Indirect Test: Detects antibodies in a sample using a labeled secondary antibody.Q11. Define an FA test, ELISA test, Western Blot, FACS and precipitation reaction.

Q11. Define an FA test, ELISA test, Western Blot, FACS and precipitation reaction.

Key Terms

• FA Test (Fluorescent Antibody Test): Uses fluorescently labeled antibodies to detect antigens.

• ELISA (Enzyme-Linked Immunosorbent Assay): Uses enzyme-labeled antibodies to detect antigens or antibodies.

• Western Blot: Detects specific proteins using antibodies after gel electrophoresis.

• FACS (Fluorescence-Activated Cell Sorting): Sorts and analyzes cells based on fluorescent labeling.

• Precipitation Reaction: Antigen-antibody reaction that forms a visible precipitate.