15 Immunology I (Immune Sys. Overview/Innate Immunity) Flashcards
3 ways the body’s immune sys responds to the presence of microbes? What does each entail?
- Tolerance (do nothing - applies to harmless microbes)
- Segregation (keep microbes away from places they shouldn’t normally be)
- Combat (mount an anti-microbial response if microbes are harmful)
Fns of the human immune system?
- Create physical/biological/chemical barrier that prevents foreign material from entering “internal” (sterile) body sites
- Tell the diff b/w things that’re foreign to the body (“non-self”) and things that are “self” (and eliminate “foreign” stuff)
- Create a “memory” of previously-encountered foreign material > faster, stronger response to re-exposures
T or F: The way the immune system deals with diff types of microbes is the same regardless of the type of pathogen.
F
The immune sys deals w/ diff types of microbes (e.g. viruses, which replicate INSIDE cells) differently than others (e.g. bacteria, which usually replicate OUTSIDE of cells)
Two types of immunity?
- Innate immunity
2. Acquired (adaptive) immunity
What is innate immunity composed of? (2)
- External barrier defenses
2. Internal cellular and biological defenses
What is adaptive immunity composed of? (2)
- Antibody-mediated (humoral) immunity
2. Cell-mediated immunity
This type of immunity responds the SAME WAY regardless of the type of microbe
Innate immunity
This type of immunity has an “individual” response designed for ea. diff microbe.
Adaptive (acquired) immunity
In innate immunity, what’re the external (surface) entry barriers? (4)
- Structural defenses (skin, mucous membranes, etc.)
- Mechanical defenses
- Microbial defenses
- Biochemical defenses
What kind of external barrier does this represent?
The skin is dry, salty envir > limits growth of microbes
Structural defenses
What kind of external barrier does this represent?
Normal microbial flora out-competes pathogenic microbes fro nutrients and for attachment sites on epithelial surfaces
Microbial defenses
What kind of external barrier does this represent?
The “flushing” action of fluids (urine, tears, saliva)
Mechanical defenses
What kind of external barrier does this represent?
Cilitated cells in lungs that move mucus toward mouth
Mechanical defenses
What kind of external barrier does this represent?
Chemicals produced by body harm microorganisms or restrict their growth
Biochemical defenses
What does lysozyme do to microorganisms?
What kind of external barrier does this represent?
Degrades peptidoglycan
Biochemical defenses.
What does lactoferrin do?
What kind of external barrier does this represent?
Binds iron> makes it unavailable as a nutrient for bacteria
Biochemical defenses.
What’re the internal cellular and biological defenses of the innate immune sys (if pathogens overcome surface barriers)? (5)
- Interferon
- Phagocytosis
- Inflammation
- Complement
- Fever
T or F: The internal cellular and biological defenses of the innate immune sys act in isolation.
F
They interact closely w/ e/o
What’s interferon? What does it do?
Small peptides produced by a virus-infected cell > It tells other cells to make anti-viral proteins
T or F: Interferons are host-specific (i.e. the human interferon is not the same as that of other mammals)
T
T or F: Interferon is highly specific for certain types of viruses.
F
They’re virus NON-SPECIFIC
How many interferons do humans make? What are they? What do ea. do?
3
INF alpha, beta, and gama
Alpha: stimulate antiviral activity
Beta: Stimulate antiviral activity
Gamma: Stimulates phagocytic cells and helps regulate the acquired/adaptive immune sys
Types of phagocytes in the body?
- Monocytes
- Neutrophils
- Eosinophils
- Macrophages
- Dendritic cells
What is phagocytosis?
When a phagocyte digests and eliminates dead tissues AND any foreign material
What types of cells are phagocytes?
WBCs
What can increases in WBC numbers, neutrophils, and bands mean?
Bacterial infection is present
What can decreases in total WBC numbers and increases in lymphocytes mean (sometimes)?
A viral infection is present (for some viruses, at least)