4/2: Immune System Flashcards
What are agranulocytes?
- Monocytes/macrophages
- Lymphocytes
What are granulocytes?
- Neutrophils
- Eosinophils
- Basophils
What are the numbers of leukocytes from most to least?
Neutrophils
Lymphocytes
Monocytes
Eosinophils
Basophils
(Never let monkeys eat bananas)
What does healthy immune system function for?
o Surveillance of the body
o Recognition of foreign material
o Destruction of entities deemed to be foreign
What is innate immunity?
- General
- second line of defense
- born with it
- Stimulated by structures common to groups of
related microbes; cannot distinguish between fine differences of foreign substances.
What are the functions of innate immunity?
inflammation, interferons,
phagocytosis, complement proteins
What is acquired immunity?
- specific
- third line of defense
- Very specific response to a distinct macromolecule, also has the ability to “remember” macromolecule and respond more vigorously to the second exposure
What are the different types of acquired immunity?
Naturally acquired: infection
Artificially acquired: active vaccinations
Passive: antibodies from mom to fetus or
immune system therapy/medications
What is acute inflammation?
- protective
- neutralizes harmful agents, removes dead tissue, and initiates the tissue repair processes
What do damaged cells release and how does this affect the inflammatory process?
Damaged cells release inflammatory mediators which stimulate the
inflammatory process, but they can also injure normal tissue.
Mediators can act
locally or systemically
How do neutrophils function in inflammation?
- Neutrophils get recruited to an area (travel through the walls of the blood vessel following chemical trail) and
inject and endocytose bacteria and fungi - At the same time, they release chemicals (IL and TNF) which recruit macrophages and lymphocytes
What are the cardinal signs of acute inflammation?
- Rubor (red)
- Calor (heat)
- Dolor (pain)
- Swelling
- Loss of function
What is phagocytosis?
non-self damaged particles are engulfed by cells through endocytosis
What is phagocytosis essential in?
Both innate AND acquired immunity
What are principle cells involves in phagocytosis?
neutrophils and macrophages, called phagocytes.
(macrophages can phagocytose far more and larger material than neutrophils)
How does phagocyte recognize non-self?
Phagocytes contain toll-like-receptors (TLR) that can recognize generic Pathogen-
Associated Molecular Patterns (PAMPs) and Damage-Associated Molecular
Patterns (DAMPs)
What are PAMPs?
bind to flagella on bacteria and activate a cascade. Leads to engulfment of whatever initially activated the TLR
What are DAMPs?
released from dead cells to signal clean up control (removes dead tissue and neutralizes harmful agents)
How do phagocytes utilize their rough surface?
Native substances have glycocalyx (protein coat that repels phagocytes)
How do phagocytes utilize opsonization?
if a target has an immunoglobulin/antibody attached to it, then it is marked for phagocytosis
▪ Example of how innate and adaptive work together!
What do vitally infected cells secrete?
INF (interferons)
What do secreted interferons (INF) cause uninfected cells to produce?
enzymes that inhibit viral replication, which prevents spread of the virus to neighboring cells
What does the complement system consist of?
30 distinct components that are in plasma in an inactive form and must be cleaved to become active
What is the difference between an antigen and an epitope?
Antigen: peptide of polysaccharide that are part of a molecule or organism
Epitope: molecular group on the antigen that is recognized by the immune
system
What is cell mediated immunity?
Activated T cells (Natural Killer and Cytotoxic T, CD8) result in killing of infected cells and stimulation of phagocytosis of bacteria and fungi
