Lecture Test 4 Part One Flashcards
(225 cards)
1
Q
what is immunology?
A
the study of all biological, chemical and physical events surrounding the function of the immune system
2
Q
what is the first line of defense?
A
any barrier that blocks invasion at the portal of entry–nonspecific
3
Q
what is the second line of defense?
A
protective cells and fluids; inflammation and phagocytosis–nonspecific
4
Q
what is the third line of defense?
A
acquired with exposure to foreign substance; produces protective antibodies and created memory cells–specific
5
Q
what are host defenses?
A
innate, natural defenses
adaptive immunities
6
Q
what are innate, natural defenses?
A
present at birth, provide nonspecific resistance to infection
7
Q
what are adaptive immunities?
A
specific, must be acquired
8
Q
what are the four major subdivisions of the immune system?
A
reticuloendothelial system (RES)
Extracellular fluid (ECF)
Bloodstream
Lymphatic system
9
Q
What is the immune system structure?
A
Large, complex and diffuse network of cells and fluids that penetrate into every organ and tissue
10
Q
What is the reticuloendothelial system?
A
Network of connective tissue fibers that interconnects other cells and meshes with the connective tissue network surrounding organs.
11
Q
What is the reticuloendothelial system inhabited by?
A
phagocytic cells, a mononuclear phagocyte system
12
Q
what is a mononuclear phagocyte system?
A
macrophages ready to attack and ingest microbes that passed the first line of defense
13
Q
What is the Lymphoid organs and tissues category classified as?
A
primary
secondary
14
Q
what are the primary lymphoid organs?
A
sites of lymphocytic origin and maturation– thymus and bone marrow
15
Q
what are the secondary lymphoid organs and tissues:
A
circulatory-based locations such as spleen and thymus and collections of cells distributed throughout body tissues- skin and mucous membranes–thymus, lymphnodes, spleen, miscellaneous
16
Q
what is the thymus?
A
high rate of growth and activity until puberty, then begins to shrink; site of T-cell maturation
17
Q
what are lymph nodes?
A
small, encapsulated, bean shaped organs stationed along lymphatic channels and large, blood vessels of the thoracic and and abdominal cavitites.
18
Q
what is the spleen?
A
structurally similar to the lymph node, filters circulating blood to remove worn out RBCs and pathogens`
19
Q
What is considered miscellaneous?
A
MALT GALT SALT BALT Appendix
20
Q
what is MALT?
A
mucosal-associated lymphoidal tissue
21
Q
what is GALT?
A
gastrointestinal-associated lymphoidal tissue (Peyer’s Patch)
22
Q
What is SALT?
A
Skin-associated lymphoidal tissue
23
Q
what is BALT?
A
Bronchial-associated lymphoidal tissue
24
Q
What is hemopoiesis?
A
production of blood cells
25
what are stem cells?
undifferentiated cells, precursor of new blood cells
26
what are leukocytes?
white blood cells
27
what are granulocytes?
lobed nucleus
28
what are the different types of granulocytes?
neutrophils
eosinophils
basophils
mast cells
29
what is the function of neutrophils?
phagocytes
30
what is the function of eosinophils?
destroy eukaryotic pathogens
31
what is the function of basophils?
release potent chemical mediators (histamine)
32
what is the function of mast cells?
nonmotile elements bound to connective tissue. they release histamine
33
what are agranulocytes?
unlobed, rounded nucleus
34
what is the function of lymphocytes?
specific immune response (b and T cells)
| 3rd line of defense
35
what are B cells?
humoral immunity: activated B cells produce antibodies
36
what are T cells?
cell mediated immunity: activated t cells modulate immune functions and kill foreign cells
37
what are monocytes and macrophages?
largest of WBCs, kidney shaped nucleus; phagocytic
38
what are macrophages?
final differentiation of monocytes
39
what are dendritic cells?
trap pathogens and participate in immune reactions
40
what are the four categories of the first line of defense:
physical barrier
mechanical barrier
chemical barrier
genetic barrier
41
what is the physical barrier?
if intact, microbes cannot penetrate
42
what are the two layers of the physical barrier?
- outer layer of skin tight layer of epithelial cells
| - mucous membrane coated with mucous with hairs or cilia
43
what is the mechanical barrier?
movement of cilia, flushing with urine or feces, blinking, coughing, sneezing
44
what is the chemical barrier?
chemicals associated with other barriers such as lysozyme, acid, salt, hydrochloric acid, digestive juices
45
what is the genetic barrier?
many microbes will only infect specific species. Parvo virus infects dogs and cats but not humans. Chickenpox virus infects humans but not dogs and cats
46
what consists of the second line of defense?
```
inflammation
phagocytosis
the complement system
fever
interferon
```
47
what is inflammation?
nonspecific defense response by the body to an injury to the tissue. It occurs after a cut, abrasion, bruise, burn or insect bite, and it aids in destruction of microbes and prevents spread, toxins and dead cells
48
what are the classic signs and symptoms of inflammation?
redness
warmth
swelling
pain
49
what is redness?
rubor--increased circulation and vasodilation in injured tissues in response to chemical mediators
50
what is warmth?
calor--heat given off by the increased blood flow
51
what is swelling?
tumor--edema; WBCs, microbes, debris, and fluid collect to form pus; prevents the spread of infection
52
what is edema?
increased fluid escaping into the tissue as blood vessels dialate
53
what is pain?
dolor--stimulation of nerve endings
54
what are the major events of inflammation?
injury, immediate reactions
vascular reactions
edema
resolution/scar formation
55
what is injury/immediate reactions?
cytokines released by tissue cells; vasoconstriction
56
what are vascular reactions?
vasodialation and seepage of fluid and out of vessels.
57
what is the major event edema?
infiltration of neutrophils (the first to arrive) and accumulation of pus
58
what is resolution or scar formation?
macrophages clean up/tissue is repaired (clean up crew)
59
what is pus?
dead cells
60
what are two unique properties of WBCs?
diapedesis
| chemotaxis
61
what is diapedesis?
migration of cells out of blood vessels into the tissues
62
what is chemotaxis?
migration in response to specific chemicals at the site of injury or infection
63
what are cytokines?
chemical mediators that regulate, stimulate, and limit immune reactions produced by WBCs and damaged tissue cells
64
what are some examples of cytokines?
histamine
interleukin 1
interleukin 2
65
what is histamine?
produced by mast cells and basophils
produced during inflammation and allergy
causes vasodialation and increased permeability
66
what is interleukin 1?
produced by macrophages
produced during specific immune response
stimulates t cells and b cells
67
what is interleukin 2?
produced by helper t cells
produced during specific immune response
stimulates proliferation of t and b cells
68
what are the general activities of phagocytes?
1. to survey tissue compartments and discover microbes, particulate matter, and dead or injured cells
2. to ingest and eliminate these materials
3. to extract immunogenic information from foreign matter
69
what cells are part of phagocytosis?
neutrophils
eosinophils
macrophages
70
how do neutrophils help with phagocytosis?
general-purpose; react early to bacteria and other foreign materials, and to damaged tissue
71
how do eosinophils help in phagocytosis?
attracted to sites of parasitic infections and antigen-antibody reactions
72
how do macrophages help with phagocytosis?
derived from monocytes; scavenge and process foreign substances to prepare them for reactions with B and T lymphocytes
73
what are toll-like receptors?
protein receptors within cell membrane of macrophages (PRRs)
74
what do toll like receptors do?
detect foreign molecules and signal the macrophage to produce chemicals to stimulate an immune response
75
what are pathogen-associated patterns (PAMPs)
molecules shared by microorganisms (peptidoglycan, outer membrane)
76
what is the mechanism of phagocytosis?
chemotaxis and ingestion
phagolysosome formation
destruction and elimination of debris
77
what is chemotaxis and ingestion?
phagocytes migrate and recognize PAMPs. They engulf microbe in a phagosome
78
what is phagolysosome formation?
lysosome fused with phagosome (death-30 minutes)
79
what is destruction and elimination of debris?
Destruction due to lysosome products: enzymes and reactive oxygen products
80
what is the complement system?
complex system that is involved at several levels of immunity. Consists of 26 blood proteins that work in concert to destroy bacteria and some viruses
81
what are complement factors?
proteins found in the blood stream produced by liver, lymphocytes and monocytes
82
the complement system works in:
a cascade reaction like blood clotting
83
the complement system is activated by
microbes, parts of microbes, cytokines and antibodies
84
what is the end product of the complement system?
membrane attack complex (MAC)
85
what is the membrane attack complex?
large, ring-shaped protein that digests holes in cell membranes of bacteria and some viruses
86
what is the function of the complement system?
MAC
acts as a chemotactic agent
stimulates inflammation
opsonization
87
what is opsonization?
coats the microbe and helps phagocytosis
88
what is the hypothalamus?
regulates body temperature to 98.6 degrees
89
what is fever?
initiated by circulating pyrogens which reset the hypothalamus to increase body temperature; signals muscles to increase heat production and vasoconstriction
90
what is pyrogen?
microbe products, blood products, vaccines and cytokines
91
sources of a pyrogen can be
exogenous or endogenous
92
what are the benefits of fever?
inhibits multiplication of heat sensitive microbes, prevents the nutrition of bacteria by reducing the availability of iron, increases metabolism and stimulates immune reactions and protective physiological processes
93
what is interferon?
small protein produced by certain WBCs and tissue cells
94
what are the three types of interferons?
interferon alpha
interferon beta
interferon gamma
95
what is interferon alpha?
lymphocytes and macrophages
96
what is interferon beta?
fibroblasts and epithelial cells
97
what is interferon gamma?
T cells
98
interferon is produced in response to
viruses, RNA, immune products, and various antigens.
99
interferon binds to:
cell surfaces and induce expression of antiviral proteins and inhibit expression of cancer genes
100
what happens if the body temperature is at 98.6 degrees and a pyrogen is present?
102 degrees and you will shiver and feel cold
101
what happens if you have a fever of 102 degrees and the pyrogen is absent?
your body temp will go back to 98.6 degrees and you will sweat and break the fever.
102
1st line is:
innate and nonspecific
103
2nd line is:
innate and nonspecific
104
3rd line is:
acquired and specific
105
what are natural killer cells
type of t cell with natural nonspecific cytotoxin powers
106
what do natural killer cells do?
circulate and are the first to destroy virus infected cells and tumor cells
107
where are natural killer cells found?
the spleen, blood, lungs, lymph nodes, bone marrow
108
what stimulates natural killer cells?
cytokines such as interferron
109
what is interferon?
cytokine produced in response to viruses, RNA, immune products and various antigens.
110
what does interferon do?
protects against viral infection of cells and cancer cells
111
what are the virulence factors of Neisseria influenza and Neisseria aeruginosa that inhibit the immune system?
they prevent MAC from creating holes in their surface.
112
what are the virulence factors of pseudomonas aeruginosa that inhibit the immune system?
it produces enzymes that inactivate complement factors
113
What is the third line of defense?
a dual system of B and T lymphocytes
114
what is an antigen?
molecules that stimulate a response by T and B cells
115
what are the two features that characterize specific immunity?
specificity
| memory
116
what is specificity?
antibodies and killer cells produced function only against the antigen that they were produced in response to
117
what is memory?
lymphocytes are programmed to recall their first encounter with an antigen and respond rapidly to subsequent encounters
118
what are the major functions of the receptors?
1. to perceive and attach to nonself or foreign monlecules
2. to promote the recognition of self molecules
3. to receive and transmit chemical messages among other cells of the system
4. to aid in cellular development
119
all of our cells also have molecules present iin the cell membrane that
tell the immune system that they belong in the body
120
the composition of natural molecules is
genetically determined
121
one important set of natural molecules is:
major histocombalitity complex MHC
122
natural molecule receptors are found on all cells except:
red blood cells
123
what is class one MHC?
markers that display unique characteristics of self molecules and regulation of immune reactions
124
Class I MHC are required for
T lymphocytes
125
what is class 2 MHC?
regulatory receptors found on macrophages, dendritic cells, and B cells
126
Class 2 MHC are involved in:
presenting antigen to T cells
127
what are foreign molecules?
also called antigens
128
what is the property of behaving as an antigen?
antigenicity
129
what is antigenicity?
foreignness
shape
size
accessibility
130
what is the molecular composition of an antigen?
```
protein
lipoprotein
glycoprotein
nucleoprotein
polysaccharides
```
131
what are lymphocyte receptors?
lymphocytes role in surveillance and recognition is a function of their receptors
132
Foreign molecules can be part of
any part of a microbe
133
what are two types of lymphocyte receptors?
B cell receptors
| T cell receptors
134
what are B cell receptors?
bind free agents not processed by APC
135
what are t cell receptors?
bind processed antigens together with the MHC molecules on the cells that present antigens to them basically processed by the APC
136
what is autoimmune disease?
when tolerance is not working and the immune system fails in distinguishing between self and non self
137
during autoimmune disease:
the body attacks its own cells
138
what are the two sides of the 3rd line?
t cells and b cells
139
what are b cells?
mature in bone marrow
become plasm cells
produce antibodies
provide humoral immunity
140
what are T cells?
mature in the thymus
become killer t cells
whole cell kills pathogen
procide cell mediated immunity
141
activation of the two sides of acquired resistance occurs in
5 stages
142
what are the five stages?
- clonal selection theory
- processing and presenting of antigen
- helper t cell activation
- b cell activation and antibody production/activated b cell
- cytotoxic T cell activation/activated cytotoxic t cell
143
what is clonal selection theory?
B lymphocytes and T lymphocytes undergo maturation before being ready to fight for the body. Lymphocytes produce a variety of receptors.
144
During clonal section theory, undifferentiated lymphocytes:
undergo a series of divisions and genetic changes that generate milliions of different cell types.
145
During clonal section theory, Both B and T cells:
undergo genetic changes to be able to respond to antigens
146
During clonal section theory, when becoming immunocompotent,
cells will have unique genes that will produce and place unique receptors on their cell surface
147
during clonal section theory, the unique receptor found on each of the cells
is what recognizes unique antigens
148
Clonal section theory is also called
lymphocyte development and differentiation
149
while lymphocytes are developing in the bone marrow,
lymphocyte stem cells differentiatie into eith T or B cells.
150
When lymphocytes are developing, B cells:
stay in the bone marrow while T cells migrate to the thymus
151
when lymphocytes are developing, both t and b cells:
migrate to secondary lymphoid tissue
152
while lymphocytes are developing, lymphocyte specificity is
preprogrammed, existing in the genetic makeup before an antigen has ever entered the system
153
While lymphocytes are developing, each genetically different type of lymphocyte
(clone) expresses a single specificity
154
what is clonal selection?
first introduction of each type of antigen into the immune system selects a genetically distinct lymphocyte and causes it to expand into a clone of cells that can react to that antigen.
155
what are the different parts of clonal selection theory?
```
the development of lymphocytes
clonal selection
B-cell maturation
T-cell maturation
Cooperation in immune reactions to antigens
```
156
where does B-Cell maturation occur?
at bone marrow sites that harbor stormal cells which nuture the lymphocyte stem cells and provide hormonal signals
157
During B-cell maturation, the cells have
immunoglobin as surface receptors for antigens
158
during b-cell maturation, the receptor placed on B cells is an
antibody molecule
| IgM or IgD
159
During B-cell maturation, millions of distinct B cells develop and
home to specific sites in the lymph nodes, spleen, and GALT
160
During a B-cells lifespan, it will
come into contact with antigens
161
what are immunoglobins?
large glycoproteins that serve as specific receptors of B cells for antigens
162
T-cell maturation is directed by
the thymus gland and its hormones
163
what is the receptor on the t cell during maturation?
two parallel proteins
164
what is CD?
cluster of differentiation
165
During T cell maturation, there are
different classes of T cell receptors (CD)
166
During T cell maturation, mature t cells
migrate to lymphoid organs
167
the T cell receptors for antigens are formed
by genetic recombination with variable and constant regions
168
the t cell receptors for antigens are 2 parallel
polypeptide chains that are small and not secreted
169
The basis for all immune responses is the encounter
between antigens and white blood cells
170
lymph nodes and speen concentrate the antigens and
circulate them so they will comeinto contact with lymphocytes
171
what is the second stage of activation?
Processing and presenting the antigen
172
During Processing and presenting the antigen, microbes entering the body are recognized by:
immune system cells
173
the macrophage is:
the antigen presenting cell (APC) of the body
174
what is the function of the macrophage?
to engulf the microbe, digest it, amd put a part of the microbe on its surface to present to a lymphocyte
175
During processing and presentation T cell dependant antigens
must be processed by phagocytes called antigen presenting cells (APC)
176
Durinf processing and presenting, APCs,
modify the antigen then the antigen is moved to the APC surface and bound to MHC receptor
177
During processing and presenting, antigen presentation involves a direct collaberation among
an APC and a T helper cell
178
During processing and presenting, interleukin 1 is secreted by
APC to activate T helper cells
179
During processing and presenting, interleukin 2 is produced by
T helper cells to activate B and other T cells
180
what is stage 3 of activation?
Helper T cell activation (CD4 cell)
181
Helper T cell activation must be
activated forst by the macrophage
182
What is the first step of helper t activation?
physical stimulus: the physcial contact between helper t and APC (must include contact with the antigen)
183
what is the second step of helper t activation?
chemical stimulus: APC secretes interleukin 1
184
After the two steps of helper T activation,
now activated helper T can assist in activating B cell and other T cells
185
What are the fourth steps of activation?
B cell activation and antibody production
| Activated B cell
186
During B cell activation, the B cell
phagocytizes and processes the microbe (no APC)
187
what is the first step that helper T activates the B cells?
Physical stimulus: physical contact between B cell and Helper T cell (must include contact with the antigen)
188
What is the second step that helper T activates b cells?
Chemical stimulus: Helper T cell secretes cytokine: interleukin 2. Now B cell is activated
189
Activated B cell undergoes change and produces:
plasma cell
| memory B cell
190
what is the plasma cell?
produces antibodies
191
what is the function of antibodies?
opsonization
activates complement
antigen-antibody aggregates
neutrilization
192
what is opsonization?
augments phagocytosis
193
what is "activates complement"
MAC (membrane attack complex)
194
what is antigen-antibody aggregates?
causes large clumps, ties up microbe
195
what is neutrilization?
microbe cannot bind target cell
196
what is memory B cell?
lives long term in the lymph tissue and is activated when subsequent exposure occurs
197
what does memory b cell produce?
lots of antibody when activated
198
what are the five classes of antibodies?
```
IgM
IgG
IgA
IgD
IgE
```
199
what is IgM?
exists as a pentamer, circulates in blood. The first antibody produced by a plasma cell
200
what is IgG?
monomer, most prevalent antibosy in fluids. The second antibody produced by plasma cell and first antibody produced by memory cells
201
IgG provides:
long term immunity
202
IgG is the only antibody
that crosses the placenta
203
what is IgA?
monomer or dimer found at the surface of membranes (saliva, mucous, tears, colostrum)
204
IgA is also called
secretory IgA
205
what is IgD?
monomer, still a mystery. Only things known are that there are small amounts in blood and it serves as a receptor on immunocompetent B cells
206
what is IgE?
monomer, uncommon in blood unless one has allergy or parasitic worm infection; stimulates histamine release
207
Neissera meningidis and neissera gonorrheae produce
IgHase which digests IgA antibody
208
During the first exposure to a microbe, the plasma cell produces
IgM in first in smaller quantities
| IgG second in larger quantities
209
During the second exposure to a microbe, the memory cell produces
LgG in large quantities (long term immunity)
210
What is the fifth stages of activation?
cytotoxic T cell activation
| activated cytotoxic T cell
211
what is the first step of cytotoxic t cell activation?
physical stimulus: APC contacts cytotoxic T cell with antigen
212
what is the second step in cytotoxic t cell activation?
chemical stimulus: helper T cell secretes interleukin 2
213
what are the two cells produced by activated cytotoxic T cell?
Killer T cell
| Memory T cell
214
what is killer T cell?
seeks out and destroys antigen containing celles with lymphotoxins
215
what are lymphotoxins?
??????
216
what is memory T cell?
lives long term in the lymph tissue and is activated when a subsequent exposure occurs
217
what are the different types of T cels?
```
T Helper cells
Cytotoxic T cells
Natural killer cells
Supressor T cells
Delayed hypersensitivity cells
```
218
what are T helper cells?
(CD4) most prevalent type of T cell
219
what is the function of helper T cells?
regulate immune reaction to antigens including other B and T cells; also involved in activated macrophages and increasing phagoctosis; differentiate into T helper 1 cells and T helper 2 cells
220
what are cytotoxic T cells?
they destroy foreign or abnormal cells by secreting granzymes and perforins that lyse cells.
221
what are natural killer cells?
lack specificity; circulate through the spleen, blood and lungs
222
what aresupressor T cells?
not well understood and are involved with dampening parts of the immune response by inhibiting proliferating B and T cells and are also iinvolved in immunologic tolerance.
223
what are delayed hypersensitivity T cells?
involved in certain allergic reactions
224
what are some examples of delayed hypersensitivity cells?
tuberculin skin tests
225
what seeks out and destroys antigen containing cells with lymphocytes during activated cytotoxic t cell?
granzymes and perforins
