Chapter 14 micro- Innate Immunity
phagosome maturation and phagolysosome formation
-membrane-bound bodies within phagocyte come in contact with and then fuse with phagosome: neutrophils have granules, macrophages have lysosomes, regardless of cell type resulting structure termed *phagolysosome*
B cells
type of lymphocyte programmed to make antibodies
natural killer cells
type of lymphocyte that induces apoptosis in cells to which antibody has bound or that lack MHC class 1 molecules on the surface and are stressed
macrophage
type of phagocytic cell that resides in tissues and has multiple roles, including scavenging debris and producing pro-inflammatory cytokines
pyroptosis
type of programmed cell death that elicits an inflammatory response
The complement system components react
In a cascade
Which role does histamine play during inflammation?
It leads to vasodilation
NOD-like receptors (NLRs)
Large family of proteins containing a nucleotide-oligomerization domain (NOD) associated with various other domains, and whose general function is the detection of microbes and of cellular stress.
A ______ contains hydrolytic enzymes to digest foreign bacteria
Lysosome
The microbe is digested within the phagocyte by enzymes delivered by a _______.
Lysosome
giant cells
very large cells with many nucleic, formed by the fusion of many macrophages during a chronic inflammatory response; found in granulomas
PAMPs (pathogen-associated molecular patterns)
Molecules associated with groups of pathogens that are recognized by cells of the innate immune system. not exclusive to pathogens
______ are the precursors to macrophages.
Monocytes
Which cell type is capable of phagocytosis?
Neutrophils and macrophages
granulocytes
wbc characterized by the presence of prominent granules; types include basophils, eosinophils, and neutrophils
After being engulfed, a microbe is found within a _______.
Phagosome
Activated complement proteins play a part in eliminating microbial invaders from a host. They belong to the group of non-specific immune responses. Which of these is NOT part of that group?
Plasma cells
The complement system comprises a group of ______ found in the bloodstream.
Proteins
cytokines
Proteins that function as chemical messengers, allowing cells to communicate
leukocytes
white blood cells
Complement proteins are found in
Serum
What is the function of selectins?
They promote sticking of neutrophils to the inner vessel wall
Complement factor C3b coats a bacterium and binds to C3b receptors on phagocytes, making the bacterium more susceptible to being phagocytized.
True
If a bacterium could escape from a phagosome, it would be able to resist digestion by that phagocyte.
True
It is possible for one host to be resistant to infection by a pathogen that can normally cause disease in a different host.
True
Margination occurs when neutrophils stick to the lining of the endothelium.
True
Phagocytosis is part of the body's innate immune defenses
True
The symptoms of inflammation are mostly due to ______.
Vasodilation
antibodies
Y-shaped glycoproteins made by B cells of the immune system in response to the presence of an antigen.
Innate lymphoid cells
a group of lymphocytes that lack specificity in their mechanism of antigen recognition; includes natural killer cells
Toll-like receptors (TLRs)
a group of pattern recognition receptors located on the surface of cells and within endosomes
lymphocytes
a group of wbc involved in adaptive immunity; B cells and T cells are examples
adhesion molecules
a molecule on one cell surface that interacts with a counter molecule on another cell causing cells to adhere together
fever
an increase in internal body temp to 37.8 degrees C
dendritic cells
antigen-presenting cells that play an essential role in the activation of naive T cells
Pro-inflammatory cytokines
any of a group of cytokines that contribute to the inflammatory response
recognition and attachment
bind directly or indirectly
C3b
binds to the surfaces of microorganisms and phagocyte receptors.
hematopoietic
bone marrow cells that give rise to all blood cells
phagocytes
cell type that specializes in engulfing and digesting microbes and cell debris
Damage-associated molecular patterns (DAMPs)
characterize damaged tissues
inflammatory mediators
chemicals such as histamine that trigger an inflammatory response when released from cells, inducers are microbes and tissue damage
granulomas
collection of lymphocytes and macrophages that accumulate in certain chronic infections; an attempt by the body to wall off and contain persistent organisms and antigens
membrane attack complex (MAC)
complement system components assembled to form pores in membranes of invading cells
inflammatory response
coordinated response with the purpose of containing a site of damage, localizing the response, eliminating the invader, restoring tissue function
The membrane attack complex kills cells by
creating holes in cell membranes
chemokine
cytokine important in chemotaxis of cells of the immune system
interleukins (ILs)
cytokines produce by leukocytes; they have diverse overlapping functions
interferons (IFNs)
cytokines that induce cells resist viral replication they also help regulate the immune response
interferons (IFNs)
cytokines that induce cells to resist viral replication, they also help regulate the immune response
antimicrobial peptides (AMPs)
defensins and other short chains of amino acids that have antimicrobial properties
destruction and digestion
destroy an invador
The three primary functions of complement activation are
enhancing phagocytosis, causing inflammation, and killing target cells
peroxidases
enzymes found in neutrophil granules, saliva, and milk that react q/ hydrogen peroxide to form antimicrobial compounds
Phagocytes are attracted by all of the following EXCEPT
enzymes released by lysosomes.
pyrogens
fever-inducing substances
Hematopoiesis
formation and development of blood cells
RIG-like receptors (RLRs)
found in cytoplasm, detect viral RNA indicating infection, produce interferons
sentinel cells
help the immune system detect signs of invasion by providing cytokines when their pattern recognition receptors recognize an invading microbe
innate immunity
host defenses involving anatomical barriers, sensor systems that recognize patterns associated with microbes or tissue damage, phagocytic cells, and the inflammatory response
host cell
in immunology one of the body's own cells; self cells
iAVPS
inactive antiviral proteins can be activated by viral dsRNA
transferrin
iron-binding protein found in blood and tissues
lactoferrin
iron-binding protein found in milk, saliva, and mucus
basophils
leukocyte with large dark-staining granules that contain histamine and other inflammatory mediators; bind to IgE
chronic inflammation
long-term inflammatory response, marked by prevalence of macrophages, giant cells and granulomas
activated macrophages
macrophages stimulated by ingesting Ag or by cytokines, greatly increased capability to kill and degrade intracellular
opsonin
molecule such as the complement system component C3b and certain antibody classes that binds to invading particles, making it easier for phagocytes to engulf them
microbe-associated molecular patterns (MAMPs)
molecules that characterizes invading microbes
mononuclear phagocytes
monocytes and macrophages
monocytes
mononuclear phagocytes of the blood; part of the mononuclear phagocyte system of professional phagocytes
Extravasation, also known as diapedesis or transmigration, occurs when
neutrophils squeeze through the blood vessel wall.
alternative pathway
pathway of complement activation initiated by the binding of a complement protein (C3b) to cell surfaces
classical pathway
pathway of complement system activation initiated by antibodies binding to antigens to form immune complexes, requires antibodies
lectin pathways
pathway of complement system activation initiated by binding of mannose-binding lectins to microbial cell walls
Phagocytosis
process in which extensions of cytoplasm surround and engulf large particles and take them into the cell
adaptive immunity
protection provided by host defenses that develop throughout life, involves B cells and T cells
inflammasome
protein complex in macrophages that activates a potent pro-inflammatory cytokine, thereby initiating an inflammatory response
pattern recognition receptors (PRR)
protein on or in cells that recognize specific compounds unique to microbes or tissue damage
surface receptors
proteins in the membrane of a cell to which certain signal molecules bind; they allow the cell to sense and respond to external signals, eyes and ears
engulfment
pseudopods surround, form phagosome
Chemotaxis
recruited to site of infection or tissue damage
erythrocytes
red blood cells
exocytosis
releases debris with cytoplasmic membrane
complement system
series of serum proteins involved with innate immunity they can be rapidly activated, contributing to protective outcomes including inflammation, lysis of foreign cells and opsonization
complement system
series of serum proteins involved with innate immunity; they can be rapidly activated, contributing to protective outcomes including inflammation, lysis of foreign cells, and opsonization
inflammation
set of signs and symptoms (swelling, redness, heat, and pain) that characterizes an innate immune response to infection or injury
actue inflammation
short-term inflammatory response, characterized by an abundance of neutrophils
tumor necrosis factor (TNF)
A cytokine that plays an important role in the inflammatory response and other aspects of immunity- cell suicide
colony-stimulating factors
A group of cytokines that direct development of various types of blood cell from hematopoietic stem cells
ligand
A molecule that binds specifically to another molecule, usually a larger one.
Antigen
A molecule that the immune system recognizes either as part of the body or as coming from outside the body. reacts specifically within an antibody or lymphocyte
T cells
A type of lymphocyte responsible for cell-mediated immunity that differentiates under the influence of the thymus.
Eosinophils
A type of white blood cell with low phagocytic activity that is thought to play a role in defense against parasitic worms by releasing enzymes toxic to these invaders.
Which of the following is NOT a function of inflammation?
Activate the complement system
Phagocytosis can be enhanced by immunological mediators such as ______.
Activated complemented proteins
Which of the following antimicrobial substances are not part of our body's first line defenses?
Antibodies
first-line defenses
the barriers that separate and shield the interior of the body from the surrounding environment
Which of the following is part of the body's adaptive defense?
B cells
How are microbes killed and digested in the phagolysosome?
By hydrolytic enzymes
The classical complement pathway is activated when
C1 binds to the antibody in an antigen-antibody complex
Both the classical and alternative complement pathways create
C3 convertase.
C3 convertase cleaves C3 into
C3a and C3b
The membrane attack complex is made from
C5b, C6, C7, C8, and C9.
Tissue injury leading to inflammation can be due to
Chemical injury, Infection, Mechanical injury
Which event occurs in the early stages of inflammation?
Chemical mediators and cytokines are released from injured cells.
What is the name of the process by which phagocytes move towards microbial products?
Chemotaxis
The four classic signs and symptoms of inflammation include all the following EXCEPT
Chills
Which of the following is part of the body's sensor systems?
Complement proteins
phagocytosis
the process by which certain cells inject particulate matter by surrounding and enveloping those materials, bringing them into the cell in phagosome
opsonization
Enhanced phagocytosis caused by coating of a particle with an opsonin
In phagocytosis, the digested contents are eliminated by ______.
Exocytosis
Mitochondria contain hydrolytic enzymes.
False
The complement system is part of the specific immune response.
False
mast cells
tissue cells similar in appearance and function to basophils of the blood, with receptors for IgE, inflammatory
