Immunology - Doc Derecho Flashcards
(306 cards)
1
Q
Study of host defense mechanisms
A
Immunology
2
Q
Ability of the host to protect itself against foreign organisms
A
Immunity
3
Q
_______, _______ and _______ mount the immune response.
A
Tissues, cells and molecules
4
Q
Ultimate function of the immune system:
A
Recognize and Destroy
5
Q
Foreign substances
A
Antigens
6
Q
Antigen + Antibody
A
Immune response
7
Q
What is the key to a healthy immune system?
A
Ability to distinguish between SELF (body’s own cells) and NONSELF (foreign cells)
8
Q
Mistake self for nonself
A
Autoimmune disease
9
Q
Cells carry _______ marker molecules
A
Self
10
Q
Cells with foreign markers
A
Antigen
11
Q
Body launches an attack
A
Immune response
12
Q
Deficient immunity results in increased susceptibility to infections exemplified by _________
A
AIDS
Defense against infections
13
Q
Boosts immune defenses and protects against infections
A
Vaccination
Defense against infections)
14
Q
Potential for immunotherapy of cancer
A
Defense against tumors
15
Q
Deficient immunity can lead to secondary infections after injury and excessive immune responses can lead to FIBROSIS and ORGAN DYSFUNCTION
A
Clearance of dead cells and tissue repair
16
Q
Immune responses are the cause of allergic, autoimmune and other inflammatory diseases
A
The immune system can injure cells and induce pathologic inflammation
17
Q
Immune responses are barriers to transplantion and gene therapy
A
The immune system recognizes and responds to TISSUE GRAFTS and newly introduced proteins
18
Q
Cells arise in ______________ and they interact with antigens in ______________
A
Primary lymphoid organs
Secondary lymphoid organs
19
Q
Primary lymphoid organ for T cells development
A
Thymus
20
Q
Primary lymphoid organ for B cell development
A
Bone marrow
21
Q
Collect antigens from tissues
A
Lymph nodes
22
Q
Collects antigens from blood stream mostly B cells
A
Spleen
23
Q
Mostly fixed macrophages (KUPFFER CELLS)
A
Liver
24
Q
Mostly B cells
A
Adenoids and tonsils
25
All immune cells begin as __________ in the bone marrow.
Immature stem cells
*They respond to different cytokines and other signals and they grow into specific immune cell types such as T cells, B cells or phagocytes.
26
Interesting possibilty for treating some immune system disorders
Stem cells
27
Can person’s own stem cells be used to regenerate damaged immune responses?
In autoimmune diseases and immune deficiency diseases
28
Immunity an organism is BORN WITH, genetically determined and effective from birth.
Innate immunity
29
Present BEFORE EXPOSURE to pathogens
Innate immunity
30
Nonspecific responses to pathogens
Innate immunity
31
Same molecules or cells respond to a range of pathogens
Non-antigen-specific
32
Same response after repeated exposure
No immune memory
33
Does not generate lasting protective immunity and no racial difference
Innate immunity
34
First line and relies on mechanisms that exist before infection.
Innate immunity
35
Rapid response to microbes
Innate immunity
36
Immediate direct response of innate immunity
0-4 hours
37
Rapid induced response of innate immunity
4-96 hours
38
Found in plants, invertebrates and vertebrates
Innate immunity
39
Immunity that an organism develops during lifetime
Adaptive immunity
*Not genetically determined.
40
Develops after exposure to antigens (microbes, toxins or other foreign substances)
Adaptive immunity
41
Very specific response to pathogens
Adaptive immunity
42
May be acquired naturally or artificially.
Adaptive immunity
43
Adaptive immunity is mediated by either:
```
Antibodies (Humoral immunity)
Lymphoid cells (Cellular immunity)
```
44
Relies on mechanism that adapt after infection.
Adaptive immunity
45
Adaptive immunity is handled by:
T and B lymphocytes
46
Adaptive immunity late response:
>96 hours
47
Is initiated if innate immune response is not adequate (> 4 days)
Adaptive immunity
48
Destroy infected cells to eradicate intracellular pathogens
T cells
49
Secrete antibodies to attack extracellular pathogens
B cells
50
Each cell responds to a single epitope on an antigen
Antigen-specific immunity
51
Generates lasting protective immunity
Adaptive immunity
52
Based upon resistance and acquired during life
Adaptive immunity
53
Relies on genetic events and cellular growth
Adaptive immunity
54
Adaptive immunity has ____________, a repeated exposure leads to faster, stronger response.
Anamnestic memory
55
The two features that best distinguish adaptive and innate immunity are ___________ and ___________.
Specificity and memory
56
Ensures that distinct antigens elicit specific responses
Specificity
57
Enables immune system to respond to a large variety of antigens
Diversity
58
Leads to enhanced respones to repeated exposures to the same antigens.
Memory
59
Increases number of antigen-specific lymphocytes to keep pace with microbes
Clonal expansion
60
Generates responses that are optimal for defense against different types of microbes
Specialization
61
Allows immune system to respond to newly encountered antigens
Contraction and homeostasis
62
Prevents injury to the host during responses to foreign antigens
Nonreactivity to self
63
Innate immunity (immediate: _______)
0-4 hours
64
Early induced response (early: _________)
4-96 hours
65
Adaptive immune response (late: _________)
>96 hours
66
Provides a barrier to prevent the spread of infection
Innate immunity
67
Identified and eliminates pathogens by:
1. Non-adaptive recognition systems
2. Activates molecules that target the microbe and aid in its identification
Innate immunity
68
Initiates an inflammatory response
Innate immunity
69
Delivers effector molecules and immune cells to the site of infection
Innate immunity
70
Provides signals to activate and regulate the type of adaptive immune response generated.
Innate immunity
71
B7 family:
CD80/86
PD-L
ICOSL
72
TNFR family
OX40L
73
Cytokines involve in innate immunity:
IL-12
IL-23
IL-4
74
Chemokines involve in innate immunity:
CXCR1
CXCR2
CCL20
75
Clinical, subclinical infection
Natural active immunity
76
Via breastmilk, placenta
Natural
77
Vaccination: live, killed, purified antigen vaccine
Artificial active immunity
78
Immune serum, immune cells
Artificial passive immunity
79
Antigens enter the body naturally; body produces antibodies and specialized lymphocytes
Naturally acquired - Active
80
Antibodies pass from mother to fetus via placenta or to infant in the mother's milk
Naturally acquired - Passive
81
Antigens are introduced in vaccines: body produces antibodies and specialized lymphocytes
Artificially acquired - Active
82
Preformed antibodies in immune serum introduced into body by injection
Artifically acquired - Passive
83
Foreign antigens enter the body
Naturally acquired active
84
Person CONTRACTS disease which generates specific immune response to the antigen.
Naturally acquired active
85
Naturally acquired active may be _________ (chickenpox or mumps) or _________ (influenza or intestinal infections)
Lifelong or temporary
86
Elicits the production of antibodies against antigens.
Humoral immunity
87
Triggers specialized lymphocytes (T-cells)
Cell-mediated immunity
88
Examples of naturally acquired PASSIVE:
1. Breastmilk
2. Colostrum
3. IgG
89
Components of breastmilk
IgA and monocytes
90
Contains BIFIDUS factors, antibodies that protect the newborn gastrointestinal tract
Colostrum
91
A type of antibody that is transplacental and protects the infant up to 3 months
IgG
92
Vaccination
Artifically acquired active
93
Diphtheria tetanus pertussis (DTP)
Artifically acquired active
94
Measles mumps rubella
Artifically acquired active
95
Polio
Artifically acquired active
96
Haemophilus influenzae type B
Artifically acquired active
97
Chicken pox
Artifically acquired active
98
Hepatitis B
Artifically acquired active
99
Collecting IgG from an infected immune person and transferring this immunity to an unprotected person
Artifically ACQUIRED passive
100
Snake antivenom injection from horses or rabbits
Artifically ACQUIRED passive
101
Used in the ttt. of tetanus, diphtheria and mumps
Artifically ACQUIRED passive
102
Sometimes given to infants who are not producing enough antibodies
Artifically ACQUIRED passive
103
B-cell immunity
Humoral
104
Antibody mediated immunity (AMI)
Humoral
105
Body develops circulating antibodies
Humoral
106
Globulin molecules in the blood plasma that are capable of attacking the invading agent
Antibodies
107
Produce the antibodies
B-lymphocytes
108
T-cell immunity
Cell-mediated
109
Formation of large numbers of activated T-lymphocytes
Cell-mediated
110
Specifically crafted in the lymph nodes to destroy the foreign agent
T-lymphocytes
111
Antibody producing cells that respond to an antigen stimulation
B lymphocytes
112
B lymphocytes are ______% of circulating lymphocytes
10-15%
113
B lymphocytes are pre-processed in the ______ during midfetal life and in the ______ during late fetal life and after birth.
Liver
| Bone marrow
114
Migrate to and are preprocessed in the THYMUS GLAND
T lymphocytes
115
80% of circulating lymphocytes
T-lymphocytes
116
Mature in bone marrow; develop from stem cells located in the red bone marrow of adults and the liver of a fetus.
B cells
117
B cells once activated proliferate into two clones of cells:
1. Plasma cells - secrete antibodies
| 2. Memory cells - that may be convered into plasma cells at a later time
118
Recognize pathogens from previous encounters
Memory cells
119
Long lived and are ready to mount an attack the next time that specific antigen presents itself.
Memory cells
120
B cells mature into ________ that produce antibodies
Plasma cells
121
Key cellular component of immunity
T cells
122
Precursors to T cells migrate to the ______ then will reach maturity then migrate to various lymph organs where they await contact with antigens.
Thymus
123
Involved in cellular immunity.
T cells
124
The 6 cells of Cell Mediated Immunity:
1. T helper 2 cells (TH2)
2. T helper 1 cell (TH1)
3. T supressor cell (TS)
4. T cytotoxic cell (TC)
5. Natural killer cell (NK)
6. Macrophage (MP)
125
Considered a type of T cell
Natural killer cell
126
The two main types of T cells each responds to one class of _________.
MHC molecule
127
Activate phagocytes to kill microbes
CD4+ T cells
128
Helper T cells have receptors that bind to peptides displayed by the body’s ________ molecules.
Class II MHC
129
CD8+ T cells
Cytotoxic T-lymphocytes (CTLs)
130
Destroy infected cells containing microbes or microbial proteins
CD8+ T cells
131
Cytotoxic T cells (Tc) have antigen receptors that bind to protein fragments displayed by the body’s __________.
Class I MHC molecules
132
T cells only recognize antigen associated with _______ on cell surfaces.
MHC molecules
133
In response to antigens found on the APC, the TH2 cells secretes _____________.
Interleukin 2 (IL-2)
134
Starts cell mediated immunity
Interleukin 2 (IL-2)
135
_______ signals other T cells specific for antigen to proliferate and become active.
IL-2
136
Recognize the non-self cell and induce APOPTOSIS (cell self death) in the viral infected or other microbial infected cell.
Cytotoxic T cells (CD8+ CTLS)
137
Killer T cell
Cytotoxic T cells
138
Cytotoxic T cells are activated by ________.
TH2 cells
139
Immunological surveillance that kills abnormal cells that arise by mutations.
Cytotoxic T cells (CD8+ CTLS)
140
Produce cytokines and direct immune response
Helper T cells (Th cells)
141
Effector mechanism that involves T- lymphocytes
Cell-mediated immune response (CMIR)
142
Eliminate intracellular microbes that survive within phagocytes or other infected cells.
Cell-mediate immune response
143
Effector mechanism that involve B-lymphocytes
Humoral immune response
144
Mediated by antibodies and eliminate extracellular microbes and their toxins.
Humoral immune response (HIR)
145
Formed as a result of antibodies produce by B plasma cells attract phagocytes which destroys pathogen
Antigen-antibody complexes
146
Cells taking part in immune response under humoral or antibody-mediated immunity:
1. APC (Macrophage or dendritic cell)
2. T cell
3. B cell
147
T cells activated by binding to certain antigens
T-independent antigens
148
No memory cells generated
T-independent antigens
149
Weaker response than T-dependent Ag
T-independent antigens
150
Most antigens require co-stimulation to evoke a B-cell response.
T-dependent antigens
151
Antibody production stimulated with help from ______.
TH
152
Most antigents are ____________.
T-dependent
153
T-dependent antigens trigger humoral response by B cells only with the participation of _______________.
Helper T cells
154
1 from many B cell (Each lymphocyte bears a specific receptor to the antigen)
Selection of B cells
155
Activation of B cells:
1. Selection of B cells
2. Recognition of antigens
3. Processing of Ag by macrophages
4. Ag presentation by macrophages to B cells
5. Triggering of the B cell by the Ab or TH cells
6. Clonal proliferation
7. Production of Plasma cells and memory cells
8. Secretion of Ig into the serum
156
Mature lymphocytes with an ANTIGEN RECEPTOR but have not encountered the antigen.
Naive lymphocytes
157
Function is antigen recognition
Naive lymphocytes
158
The preferential migration of naive lymphocytes is to _________________, the sites where antigens are concentrated and immune responses start.
Peripheral lymphoid organs (lymph nodes)
159
Have received confirmation of the danger of the antigen and are able to PROLIFERATE MORE LYMPHOCYTES SPECIFIC FOR THAN ANTIGEN.
Activated lymphocytes
160
Descendants of activated lymphocytes
Effector lymphocytes
161
Capable of performing the functions required to eliminate microbes (“effector molecules”)
Effector lymphocytes
162
Responsible for cytokine secretion (helper cells) and killing of infected cells (CTLs)
Effector lymphocytes
163
Long-lived descendants of activated lymphocytes
Memory lymphocytes
164
Functionally SILENT CELLS
Memory lymphocytes
165
Can revert back to activated lymphocytes with stimulation from the same antigen.
Memory lymphocytes
166
Mount rapid responses to antigen challenge (secondary responses)
Memory lymphocytes
167
Most CLONE CELLS become _____________.
Antibody-secreting plasma cells (effector cell-short-lived cells)
168
___________ secrete specific antibody at a higher rate than B cells.
Plasma cells
169
Production of specific clones of effector T cells and memory clones
Primary response
170
Develops in several days and DOES NOT limit the infection
Primary response
171
More pronounced, faster and more effective at limiting the infection.
Secondary response
172
Cytotoxic reactions against intracellular parasites
Secondary response
173
Delayed hypersensitivity (e.g Tuberculin test)
Secondary response
174
Allograft rejection
Secondary response
175
Under primary response, _________ to antigen produces NO ANTIBODIES in serum for several days.
Initial exposure
176
Primary response has a gradual INCREASE in titer. First of IgM and then of IgG observed after ________ days.
3 to 6
177
Most B cells become plasma cells. Some B cells become long living memory cells.
Primary response
178
Peak levels of plasma antibody after a primary response are achieved in _________ and gradual DECLINE of antibodies follows.
10 days
179
Subsequent exposure to the same antigen displays a FASTER and MORE INTENSE Ab response within an hour.
Secondary response
180
It is due to the existence of __________ which rapidly produce plasma cells upon antigen stimulation.
Memory cells
181
In secondary response, antibody levels peak in ____________.
2 to 3 days
182
Antibody levels in the blood can remain HIGH FOR WEEKS TO MONTHS.
Secondary response
183
Memory cells initiate a faster, more efficient response upon reinfection.
Immunity
184
The antibody marks the antigen for destruction.
Antigen-antibody interlock
185
Antigen is derived from two words:
ANTIbody GENerator
186
Most antigens are __________ or ____________.
Proteins or large polysaccharides
187
When an antigen elicits an immune response it is often referred to as a ___________.
Immunogen
188
Reactive portion of the antigen
Epitope
189
Reacts chemically with an antibody to form the antigen-antibody complex or immune complex.
Epitope
190
Two essential properties of antigens include:
1. Immunogenicity
| 2. Ability to stimulate immune system
191
Belong to a family of large molecules known as IMMUNOGLOBULINS
Antibodies
192
Antibodies belong to the gamma-globulin fraction of serum proteins called _______________.
Immunoglobulins (Igs)
193
Has two identical antigen-binding sites
Immunoglobulins
194
Specific for the epitope that provides it production
Immunoglobulins
195
Y shaped or T shaped polypeptides
Antibodies
196
Antibodies consist of ____ POLYPEPTIDES
4
197
Antibodies are covalently linked by ___ disulfide bonds.
4
198
This is the part of the antibody that binds to the antigen.
Fab region
199
The stem of the antibody that functions as a “red flag” and notifies the rest of the immune system: “here I am come and help”
Fc region
200
2 constant regions
Fc fragment and crystallizable
201
2 variables regions
Fab fragment and antigen binding
202
Contain hypervariable amino acid sequences
Variable regions
203
Bind antigen (specific immunity)
Hypervariable regions
204
Most common form
IgG
205
First response to antigen
IgM
206
Secreted from mucus membranes
IgA
207
B cell activation
IgD
208
Histamine reactions and allergies
IgE
209
Cannot cross placenta
IgD
210
Prevents attachment of bacteria to epithelial surface
IgA
211
Effective in agglutination
IgM
212
Crosses blood vessels
IgG
213
Cannot cross placenta
IgM
214
Crosses placenta (passive immunity to fetus)
IgG
215
Monomeric and 70-75% of total immunoglobulin
IgG
216
Pentameric and cannot cross the placenta
IgM
217
Monomeric in SERUM
IgA
218
Secreted in high quantities in SECONDARY EXPOSURES
IgG
219
Secreted first during exposure
IgM
220
5-10% of serum antibody
IgA
221
IgG 4-fold rise or fall means:
Active infection
222
Activates the complement
IgM
223
DIMERIC with secretory component in the lumen of the GI tract and in respiratory tract
IgA
224
Opsonize antigens for phagocytosis
IgG
225
Used as a marker of RECENT INFECTION
IgM
226
Neutralizes microbes and toxins
IgA
227
Neutralizes toxins and viruses and can activate the complement
IgG
228
Presence of IgM in newborns means __________.
Infection
229
Sero-diagnosis of tuberculosis
IgA
230
Protects the fetus and newborn (passive immunity)
IgG
*only Ig transferred across the placenta
231
Single positive of IgM in serum or CSF indicates:
Recent or active infection
232
Synthicial respiratory virus tests
IgA
233
Circulates in the blood but can easily exit to the tissues
IgG
234
Detect early phase of infection
IgM
235
Provides localized protection on mucosal surfaces
IgA
236
MOST ABUNDANT circulating antibody
IgG
237
Especially effective against microorganisms and clumping antigens
IgM
238
Most common form
IgG
239
First antibodies produced in response to a MILD INFECTION
IgM
240
Are circulating antibodies found in the circulatory system with IgG
IgM
241
IgG or IgM reacts with epitopes on the host cell membrane and activates the ______________
Classical component pathway
242
Causes lysis of the cell
Membrane attack complex
243
Produced as a first response to many antigens
IgM
244
Levels remain HIGH TRANSIENTLY
IgM
245
Produced after IgM
IgG
246
Higher levels persist in small amounts throughout life
IgG
247
Produced in large amounts during secondary response
IgG
248
Persistence of antigen sensitive “memory cells” after primary response
IgG
249
Found in mucus, tears, saliva, sweat, blood and human milk
IgA
250
Protects surface tissues and prevents adherence of microorganisms
IgA
*This is important in respiratory, gastrointestinal and genitourinary tract infections
251
True or False:
IgD is monomeric.
True
252
Present on the surface of B lymphocytes functions in the initiation of an immune response
IgD
253
0.2% of serum antibody
IgD
254
Functions as MEMBRANE RECEPTOR
IgD
255
Has a role in antigen stimulated lymphocyte differentiation
IgD
*Role unclear
256
Effects of complement system:
1. Enhances inflammatory response (Attracts phagocytes)
2. Increases phagocytosis through opsonization or immune adherence
3. Creates membrane attack complexes (cytolysis)
257
Series of 30 plasma (serum) proteins activated in a cascade
Complement system
258
Work together to “complement” the action of antibodies in destroying bacteria
Complement system
259
Plays a role in the initiation of the inflammatory response
IgE
260
Found in the BLOOD SERUM
IgE
261
Also rid the body of antibody-coated antigens (antigen-antibody complexes)
Complement system
262
Plays a role in immunity to helminthic parasites
IgE
263
Possibly involved in the lysis of parasitic worms
IgE
264
IgE are antibodies responsible for ____________.
Allergic reaction
265
Principal actors in the complement system are 11 proteins:
C1 through C9
| B and D
266
0.002% of serum antibody
IgE
267
Mediates type I hypersensitivity
IgE
268
Associated with ANAPHYLAXIS
IgE
269
Serodiagnosis of infectious and noninfectious allergies (allergic bronchopulmomary aspergillosis, parasitic diseases)
IgE
270
Does not require a specific antibody to get started.
Alternative pathway
271
Can be triggered by infectious agents in absence of antibody
Alternative complement pathway
*It has the same terminal sequence of events as the classical pathway
272
Alternative complement pathway does not require _____, _____ or ______.
C1, C2 or C4
273
Combines with factors B, D and P on the surface of a microbe
C3
274
No antibody involved, once C3a and C3b are formed they participate in cytolysis, inflammation and opsonization
Alternative complement pathway
275
Does nor require a specific antibody to get started.
Lecithin pathway
276
Effects of complement activation:
1. Opsonization or immune adherence: enhanced phagocytosis
2. Membrane attack complex: Cytolysis
3. Attract phagocytes
277
Coat bacteria and promote attachment of micoorganism to phagocyte
Opsonin (complement proteins or antibodies) / Opsonization
278
Prevent complement activation
Capsules
279
Prevent MAC
Surface lipid-carbohydrates of some gram-negatives
280
Enzymatic digestion of _______ by gram positives
C5a
281
A drug given to transplant patients in order to block immunological rejection
Cyclosporin
282
Cyclosporin blocks synthesis of ________.
IL-2
283
Makes sure markers of self on the donor's tissue are as similar as possible to those of the recipient.
Tissue typing
284
Each cell has a double set of ____ major tissue antigens and each of the antigens exists.
6
285
In bone marrow transplants, a _________ is extremely important.
Close match
286
Type I hypersensitivity occurs within _______ after exposure to allergen.
30 minutes
287
The _____ of IgE binds to mast cells or basophils.
Fc
288
When IgE binds to allergens, ___________ are released.
Fluid phase mediators
289
Uses patient's serum to measure specific IgE.
RAST (radioimmunoassay test)
290
Takes 5-12 hours
Type II hypersensitivity
291
Involves TC cell or antibody plus complement lysis
Type II hypersensitivity
292
Incompatible blood transfusion
Type II HPS
293
Erythroblastosis fetalis
Type II HPS
294
Thrombocytopenic purpura
Type II HPS
295
Occurs in 3-8 hours
Type III HPS
296
Requires Ab+ slight excess of solubilized antigen
Type III HPS
297
Activation of complement
Type III HPS
298
Precipitation of immune complex in sensitive tissues
Type III HPS
299
Occurs in 24-48 hours
Type IV HPS
300
Allergic contact dermatitis to gold and other metal and poison ivy
Type IV HPS
301
Indurated hard bump consisting of macrophages signaled by thee TH1 cell to migrates to the site of specific antigen
Type IV HPS
302
Glomerulonephritis
Type III
303
IDDM (juvenile onset diabetes)
Type IV HPS
304
Systemic lupus erythematosus
Type IV
305
Rheumatoid arthritis
Type III
306
From loss of self tolerance
Autoimmune disease
