Final Exam: Immunology Flashcards
(157 cards)
1
Q
T or F:
Lysozyme is an enzyme that damages the peptidoglycan in bacterial cell walls.
A
True
2
Q
T or F:
Activation of complement always required antibodies
A
F
3
Q
T or F:
Capsules and cell wall proteins allow some bacteria to evade the adherence step of phagocytosis
A
True
4
Q
T or F:
He symptoms of inflammation include redness, heat, swelling, and pain
A
True
5
Q
Which type of WBC is capable of phagocytosis?
Neutrophil or lymphocyte
A
Neutrophil
6
Q
What step of phagocytosis is improved by opsonization?
A
Adherence
7
Q
Which cell type forms scar tissue?
A
Stromal cells
8
Q
Which of these molecules is produced in response to viral infections?
Prostaglandins or interferons?
A
Interferons
9
Q
First line of defense again microbes?
A
Skin and mucous membranes
10
Q
What group of serum proteins is involved in cytolysis of microbes?
A
The complement system
11
Q
List the five types of WBC from most to least abundant
A
Neutrophils, lymphocytes, monocytes, eosinophils, basophils
12
Q
Which type of cells mature to form a macrophage?
A
Monocytes
13
Q
What is the term for the widening of blood vessels?
A
Vasodilation
14
Q
What type of immunity targets specific microbes?
A
Adaptive immunity
15
Q
Example of first line defense?
A
The ciliary escalator
16
Q
What is the term for the movement of phagocytes trough a blood capillary walk to the site of infection?
A
Emigration
17
Q
Which protein gives strength and toughness to epidermal tissue?
A
Keratin
18
Q
General term for all white blood cells?
A
Leukocyte
19
Q
What encloses a microbe inside a phagocytic cell?
A
A phagosome
20
Q
Cells produce alpha interferon and beta interferon in response to
A
Viral infections
21
Q
Which of these cells do not have phagocytic activity?
A
Lymphocytes
22
Q
Which complement protein directly forms the membrane attack complex? (MAC)
A
C9
23
Q
Which complement protein binds to the surface of microbes and enhances phagocytosis in a process termed opsonization?
A
C3b
24
Q
What is not a chemical factor that helps the skin be relatively resistant to infections?
A
Complement proteins
25
What term best describes the symbiotic relationship between humans and most of the normal microbiota that live on our human skin?
Commensalism
26
______ are involved in detecting foreign invaders. They do so by binding to pathogen- associated molecular patterns on the surface of pathogen
Toll-like receptors
27
The presence of a capsule and the M protein of streptococcus pyogenes are both involved in
Helping bacteria resist phagocytosis
28
______ are inflammatory molecules that are usually found in blood in an inactive form. Once activated they help to attract neutrophils to the injured area
Kinins
29
When attracted to an infected area, macrophages can leave the bloodstream by squeezing grouch the endothelial cells lining a blood vessel. What is this process called?
Diapedesis
30
What is the effect of alpha interferon on an uninflected cell?
It causes the cell to produce antiviral proteins
31
What is the fluid that is collected by the blood by lymphatic capillaries?
Interstitial fluid
32
What is not an advantage of antimicrobial peptides?
They have a narrow spectrum of activity, so they are very specific
33
Chronological order of phagocytosis
Chemotaxis, adherence, ingestion, digestion
34
Which is false about lysozyme?
It is an organelle in white blood cells
35
Your lab partner slips on his way to class and scraped his arm. You make a smear of the fluid and observe large nucleated cells. These are most likely
Neutrophils
36
Edema is a collection of fluid in an area of the body. What is the physiological change that causes edema?
Increased permeability of blood vessels.
37
What structure is not associated with innate immunity?
Antibodies
38
The epidermis
Contains the protein keratin
39
The ID50 for many pathogens is significantly smaller when testing with gnotobiotic animals compared to animals with normal microbiota. This is likely because of
Microbial antagonism
40
The respiratory system is protected against harmful microbes by all of the following except
The lacrimal apparatus
41
Which of the statements is not true or sebum
It raises the pH of the skin
42
One remarkable finding on a patient's laboratory workup is a marked eosinophilia. This might be suggestive of
Either a parasitic infection or an allergic reaction
43
Which of these structures are not part of the mononuclear phagocytic system
Lymphocytes
44
What is not true for bacterial destruction by phagocytosis?
Myeloperoxidase in the lysosomes is involved in the formation of HOCl
45
The stage of phagocytosis in which the phagocyte's plasma membrane attaches to the surface of the microbe is called
Adherence
46
Activation of the complement cascade
Can cause the infecting microbe to be killed by lysis
47
Complement can be activated by all but
The presence of a host tissue
48
Assume you mis red blood cells, antibodies against red blood cells, and complement in a test tube. What would happen?
Lysis of the red blood cells
49
Complement component C3, in the classical pathway, is split by
C2aC4b
50
Which occurs first, setting in motion the remaining events?
Toll-like receptors in macrophages and dendritic cells attach to pathogen-associated microbial patterns on invading microorganisms
51
Interferons
A host-specific but not virus-specific
52
What is innate immunity?
It is nonspecific, and is made up of the defenses present at birth.
Host defenses that afford protection against any kind of pathogen
53
Innate immunity has
```
Physical barriers
Chemical barriers
Mechanical barriers
Inflammation
Phagocytosis
Complement
Interferon
```
54
How do normal microbiota protect us?
Provide competition for nutrients that helps prevent potential pathogens from colonizing tissues.
55
What is a differential white blood cell count
The number of each kind of leukocyte in a sample of 100 leukocytes
56
Monocytes develop into
Macrophages
57
First line of defense in innate immunity
Skin
Mucous membranes
Normal microbiota
58
2nd line of defense in innate immunity
Phagocytic white blood cells
Inflammation
Antimicrobial compounds
59
3rd line defenses of innate immunity
Adaptive immune response
60
Tightly packed skin cells are what kind of barrier?
Mechanical
61
Mucous membranes use what kind of mechanisms?
Flushing mechanisms
62
What protects lungs from particles?
A chemical barrier called the ciliary escalator
63
Antimicrobial chemical factors in skin and mucous membranes
* Skin: forms sebum, which lowers pH and inhibits microbial growth
* Gastric juice: in stomach with pH between 1 & 3
* perspiration and tears: contain lysozyme, an enzyme that damages the peptoglycan in bacterial cell walls.
64
Lysozyme:
An enzyme that damages the peptoglycan in bacterial cell walls
65
White blood cells consist of
Granulocytes and agranulocytosis
66
Granulocytes are / consist of
Primarily pathogenic and consist of neutrophils, eosinophils, and basophils
67
Agranulocytes consist of
Monocytes and lymphocytes
68
What percent of white blood cells are neutrophils and what are basophils
Neutrophils: 60-70%
Basophils: <1%
69
Dendritic cells are
White blood cells that are not found in blood, but in skin, mucous membranes, and lymph nodes. Help to initiate immune responses
70
Phagocytic cells are primarily
Neutrophils and macrophages
71
Phagocytic cells can
Pass through blood capillary walks to reach sites of infection in the tissues. Engulf microbes by phagocytosis
72
Phagocytosis is defined as:
The ingestion of solid material by a eukaryotic cell
73
The phagocytes of the immune system include
Macrophages and neutrophils
74
Steps of phagocytosis
```
Chemotaxis
Adherence
Ingestion
Digestion
Elimination (exocytosis)
```
75
What would be a chemotactic chemical attracting a phagocyte to a site of infection?
Peptide from the complement system
76
Which step of phagocytosis is enhanced by opsonins
Adherence
77
Which describes a process involving phagolysosomes?
Fusion between a phagosome and a lysosome, digestion of bacterium in 10-30 minutes, fusion with the plasma membrane during elimination
78
Antigen processing a presentation occurs during
Elimination
79
What is fever?
An abnormally high body temperature, a third component of the second line of defense
80
What is the most frequent cause of fever?
Infection from bacteria or viruses
81
Antibodies are what?
Proteins
82
7 steps of phagocytosis
* Chemotaxis and adherence of microbe to phagocyte
* ingestion of microbe to phagocyte
* Formation of phagosome
* Fusion of phagosome with a lysosomes to form a phagolysosome
* Digestion of ingested microbe by enzymes
* Formation of residual body containing indigestible materials
* Discharge of waste materials
83
Antimicrobial peptide
An antibiotic that is bactericidal and has a broad spectrum of activity
84
Natural killer cell
A lymphoid cell that destroys tumor cells and virus-infected cells
85
Membrane attack complex
Complement proteins C5-C9, which together make lesions in cell membranes that lead to cell death
86
Fimbria
An appendage on a bacterial cell used for attachment
87
Histamine
A substance released by tissue cells that causes vasodilation, capillary permeability, and smooth muscle contraction
88
Granzymes
Proteins that induce apoptosis
89
Cytokine
A small protein released from human cells that regulates the immune response; directly or indirectly may induce fever, pain, or T cell proliferation
90
PAMP (pathogen-associated molecular patterns)
Molecules present on pathogens and not self
91
Abscess
A localized accumulation of pus
92
Hematopoeisis
The formation of blood cells
93
Eosinophils
A granulocyte whose granules take up the stain eosin
94
Resistance
The ability to ward off diseases through innate and adaptive immunity
95
Leukotriene
A substance produced by mast cells and basophils that causes increased permeability of blood vessels and helps phagocytes attach to pathogens
96
Lymphocyte
A leukocyte involved in specific immune responses
97
Complement
A group of serum proteins involved in phagocytosis and lysis of bacteria
98
TCRs (T cell receptors)
Molecules on T cells that recognize antigens
99
Mucous membranes
Membranes that line the body openings, including the intestinal tract, open to the exterior; also called mucosa
100
Interferon
A specific group of cytokines. Alpha and beta interferons are antiviral proteins produced by certain animal cells in a response to a viral infection. Gamma-IFN stimulates macrophage activity
101
Protein kinase
An enzyme that activates another protein by adding a p from ATP
102
Phagosome
Food vacuole of a phagocyte; also called a phagocytic vesicle
103
Lectin
Carbohydrate-binding proteins on a cell, not an antibody
104
Kinin
A substance released from tissue cells that causes vasodilation
105
Perforin
A protein that makes a pore in a target cell membrane, released by cytotoxic T lymphocytes
106
Inflammation symptoms
Redness, swelling, heat, pain
107
What does inflammation do?
Rapidly confines and destroys infectious agents. Damaged tissue can be repaired and replaced. Begins w injury, excessive heat, or harsh chemicals.
108
Steps of inflammation
1. Vasodilation
2. Chemical signals attract phagocytes
3. Tissue repair
109
Two types of antimicrobial groups
Complement system and interferons
110
Three pathways in complement system
1st/classical pathway: requires specific antibodies, antibody production occurs in adaptive immunity
2nd & 3rd: do not require antibodies. Activated when serum proteins bind microbial polysaccharides and initiate the complement cascade. Activation of this causes lysis of microbes
111
What do interferons do?
Interfere with replication or viruses and other pathogens
112
Types of interferons
Alpha, beta, and gamma
113
How are alpha and beta interferons produced?
By cells infected w viruses
114
How are gamma interferons produced?
By lymphocytes.
115
Fixed macrophage
A macrophage that is located in a certain organ or tissue. Aka a histiocyte
116
Free (wandering) macrophage
A macrophage that leaves the blood and migrates to infected tissue
117
Adaptive immunity
Forms in response to the specific pathogens that you encounter during your life
118
What are antigens?
Something that stimulates an immune response
119
Leukopenia
Decrease in certain WBC levels
120
Leukocytosis
Increase in certain WBC levels
121
5 antibody classes
```
IgG
IgA
IgM
IgE
IgD
```
122
Humoral immunity
Immunity produced by antibodies dissolved in body fluids, mediated by B cells; also called antibody-mediated immunity
123
Antibodies
Protein produced by the body in response to an antigen, and capable of combing specifically with that antigen
124
B cell
A type of lymphocyte, differentiates into antibody-secreting plasma cells and memory cells
125
B cells are named for what?
The bursa of Fabricius.
126
What is the site of creation and maturation of B cells?
The red bone marrow
127
T cells
Type of lymphocyte that develops from a steel cell processed in the thymus gland. That is responsible for cell-'delayed immunity.
128
Cellular immunity
An immune response that involves T cells binding to antigens presented on antigen-presenting cells; T cells differentiate into several types of effector T cells. Also called cell-mediated immunity b
129
Where do T and B cells develop from?
Stem cells in the bone marrow.
130
T cells mature under the influence of the
Thymus
131
Where are B and T cells primarily found?
Blood and lymphoid organs.
132
Antibody: IgG
About 80% of all antibodies in serum. Cross walls of blood vessels and enter tissue fluids in areas of inflammation. Can cross placenta to confer passive immunity to fetus. Protect against circulating bacteria and viruses, neutralize bacterial toxins, trigger the complement system, and when bound to antigens enhance effectiveness of phagocytic cells
133
Antibodies: IgM
M refers to macro, large. Make up 6% of antibodies in serum. Has a petarme structure consisting of five monomers held together by a polypeptide called a joining chain. Does not move as freely due to size, generally remain in blood vessels. Causes clumping or cells and viruses
134
Why is IgM valuable in diagnosing a disease?
It appears first in response to a primary infection and is relatively short lived
135
Antibodies: IgA
13% of antibodies in serum, but is most common form in mucous membranes and in secretions such as mucus, saliva, tears, and breast milk. Monomer
Is present in breast milk and can help protect infant from gastrointestinal infections
136
Antibodies: IgD
Only about .02% of serum antibodies. Structure resembles IgG. Found in blood, lymph, and particularly on the surface of B cells. Assist in immune response on B cells
137
Antibodies: IgEs.
Slightly larger than IgG. Only .002% of serum antibodies. Bind tightly by their Fc regions to receptors on mart cells and basophils. Mediates allergies. Get rid of parasites
138
Actively acquired immunity:
When a person is exposed to a microorganism or foreign substance and the immune system responds
139
Passively acquired immunity:
Acquired passively when antibodies are transferred from one person to another.
140
Vaccination
The process of conferring immunity by administering a vaccine; also called immunization
141
What do antibodies react with?
Antigens
142
Plasma cell
A cell that an activated B cell differentiates into; plasma cells manufacture special antibodies
143
Memory cells
Long lived, responsible for the enhanced secondary response to an antigen
144
Self-tolerance
The immune system's ability to discriminate self from nonself
145
A T-cell will attack its own tissue cells without
Self tolerance
146
What are the four types of hypersensitivities
I: allergy
II: cytotoxins
III: immune complex toxins
IV: delayed hypersensitivity
147
Which hypersensitivities can cause autoimmunity?
Types II-IV
148
What is autoimmunity?
When immune system attacks itself
149
Is the sensitizing exposure always the first exposure to an antigen?
No, an allergy can develop any time of life
150
Sensitizing exposure:
Body creates antibodies against an antigen
151
Desensitization
Body begins to create IgG antibodies to antigen which compete with IgE antibodies.
152
IgE antibodies activate:
Basophils
153
In type II hypersensitive (cytotoxins)
IgG and/or IgM antibodies bind to antigen
154
What is hemolytic disease of the newborn (HDN)
An Rh- mom carries and Rh+ baby, mom becomes sensitized to Rh factor potentially, first baby is fine. 2nd pregnancy w Rh- baby, antibodies cross placenta and attack baby's red blood cells, becomes severely anemic. Can result in miscarriage or other issues.
155
How can HDN be prevented?
Prenatal care, given medicine called Rh immunoglobulin which can stop antibodies from reacting to your baby's Rh+ cells
156
Passive immunity is ______ while active immunity is ______
Temporary; long term
157
What is type IV hypersensitivity (delayed hypersensitivity) mediated by?
T-cells
