Immunology 2 Flashcards
1
Q
What do Interferon Alpha and Beta do?
A
Part of the innate immune systems defence against both RNA and DNA. Interferons are glycoproteins synthesized by viral-infected cells that act locally on uninfected cells, “priming” them for viral defense.
2
Q
What are the two steps of “priming” interferon Alpha and Beta?
A
- RNAase L - degradation of viral/host mRNA2. Protein kinase - inhibition of viral/host protein synthesis These two steps essentially result in apoptosis, thereby interrupting viral amplification
3
Q
Where do we find/see cell surface proteins?
A
All cells except mature RBCs have MHC1
4
Q
What cell surface receptors are present on T cells?
A
TCR (bind antigen-MHC complex)CD3 (associated with TCR for signal transduction) CD28 (binds B7 and APC)
5
Q
What cells surface receptors are present on Helper T Cells?
A
CD4, CD40l
6
Q
What cell surface receptors are present on Cytotoxic T cells?
A
CD8
7
Q
What cell surface receptors are present on B cells?
A
Ig (binds antigen)CD19, CD20, CD21 (receptor for EBV)CD40MHC2, B7
8
Q
What cell surface receptors are present on Macrophages?
A
CD14, CD40MHC2, B7Fc and C3b receptors (enhance phagocytosis)
9
Q
What cell surface receptors are present on NK cells
A
CD16 (binds Fc of IgG)CD56 (unique marker for NK)
10
Q
Define Anergy
A
A state of immune unresponsiveness
11
Q
What effects can bacterial toxins have?
A
- Pathogens like S. progenies and S. aureus, cross-link the Beta region of the T-cell receptor to the MHC class 2 on APCs.
- Can activate any T cell, leading to massive release of cytokines
- Endotoxins/lipopolysaccharide (gram-negative bacteria) - directly stimulate macrophages by binding to endotoxin receptor CD14; Th cells are not involved
12
Q
Define Antigenic Variation
A
Mechanism by which an infectious organism such as a protozoan, bacterium or virus alters its surface proteins in order to evade a host immune response
13
Q
Provide an example of antigenic variation
A
- DNA rearrangement
- RNA segment reassortment (eg. influenza major shift)
14
Q
How do you acquire passive vs. active immunity
A
passive = receiving preformed antibodies active = exposure to foreign antigens
15
Q
Describe the difference in the onset of passive vs. active immunity
A
Passive = rapid Active = slow
16
Q
Compare duration of a passive vs. active immune response
A
Passive = short lasting Active = long lasting
17
Q
Name 4 pathogens, given as vaccines, that provide passive immunity via preformed antibodies
A
TO BE HEALED RAPIDLY - Tetanus, Botulinum toxin, HBV, Rabies vaccines
18
Q
What other terms/words are used in the place of active immunity?
A
Active immunity = humoral immunity = cellular immunity
19
Q
Describe Live Attenuated Vaccines
A
Microorganism loses its pathogenicity but retains capacity for transient growth within inoculated host. Mainly induces a CELLULAR RESPONSE
20
Q
Describe Inactive or Killed Vaccines
A
Pathogen is inactivated by heat or chemicals; maintains epitope structure on surface antigens is important for immune response. HUMORAL IMMUNITY induced.
21
Q
List 1 pro and 1 con of live attenuated vaccines
A
PRO - induced strong, often lifelong, immunity
CON - may revert to virulent form, Often contraindicated in pregnancy and immune def.
22
Q
List 1 pro and 1 con of inactived/killed vaccines
A
PRO - stable and safer than live vaccines
CON - weaker immune response; booster shots are usually required
23
Q
List some live attenuated vaccines
A
MMRPV
- measles
- mumps
- rubella
- polio (Sabin)
- influenza
- varicella
- yellow fever
24
Q
List some inactivated/killed vaccines
A
- cholera
- hep A
- Polio (Salk)
- Influenza (inj)
- rabies
25
What type of reaction is a type 1 hypersensitivity response?
Anaphylactic and atopic (First and Fast)
26
Which types of hypersensitivity reactions are antibody mediated?
Types 1,2 and 3
27
How do type 1 hypersensitivity reactions work?
- free antigen cross-links IgE on a pre-sensitized mast cells and basophils.
- This triggers immediate release of vasoactive amines that act as post capillary venues (i.e histamine).
- This reactions develops quickly because of preformed antibodies
- delayed response follows due to production of arachadonic acid metabolites (e.g leukotrienes)
28
What is responsible for the rapid response of type 1 hypersensitivity?
preformed antibodies (e.g. histamine)
29
What is responsible for the delayed response that follows the rapid response of the type 1 hypersensitivity?
arachadonic acid metabolites (e.g leukotrienes)
30
What types of reaction is a type 2 hypersensitivity?
Cytotoxic
31
How do type 1 hypersensitivity reactions work?
IgM, IgG bind to fixed antigen on "enemy" cells, leading to cellular destruction.
3 mechanisms
1. opsonization leading to phagoctosis or compliment activation
2. complement-mediated lysis
3. antibody- dependent cell-mediated cytotoxicity, usually due to NK cells or macrophages
32
How do type 3 hypersensitivity reactions work?
Imagine an immune complex with 3 things stuck together - antigen, antibody, complement.
This complex activates complement, which attracts neutrophils; neutrophils release lysosomal enzymes
33
What types of hypersensitivity reaction is responsible for serum sickness?
Type 3
34
How does serum sickness arise?
A type 3 hypersensitivity response by the immune system.
An immune complex forms in which antibodies to the foreign proteins are produced (takes 5 days). Immune complexes form and are deposited in membranes, where they fix complement (leads to tissue damage). More common than Arhus reaction.
35
What are the symptoms of serum sickness?
Fever, urticaria, arthralgias, proteinuria, lymphadenopathy, 5-10 days after antigen exposure
36
What is an arthrus reaction?
A local, subacute antibody mediated hypersensitivity (type 3) reactions.
Intradermal injection of an antigen induces antibodies, which form antigen 0 antibody complexes in the skin.
37
What are the symptoms of Arthrus Reactions?
Edema, necrosis, activation of complement
38
What causes Arthrus reactions?
Antigen-antibody complexes
39
What is another name for Type 4 hypersensitivity?
Delayed (T cell mediated) hypersensitivity
40
How does Type 4 hypersensitivity work?
Sensitized T lymphocytes encounter antigen and then release lymphokines (leads to macrophage activation; no antibody involved)
41
List the 4 types of hypersensitivity reaction with their number and name
Type 1, anaphylactic and atopic
Type 2, Cytotoxic
Type 3, Immune complex
Type 4, Delayed (T cell mediated) type
42
What types of hypersensitivity reaction causes anaphylaxis?
Type 1
43
What types of hypersensitivity reaction causes allergies atopically
type 1
44
What types of hypersensitivity reaction causes SLE
type 3
45
What types of hypersensitivity reaction causes Autoimmune hemolytic anemia?
type 2
46
What types of hypersensitivity reaction causes Pernicious anemia?
type 2
47
What types of hypersensitivity reaction causes MS?
Type 4
48
What types of hypersensitivity reaction causes Polyarteritis nodosa?
Type 3
49
What types of hypersensitivity reaction causes idiopatic throbocytopenia purpora
Type 2
50
What types of hypersensitivity reaction causes Erythroblastosis fettles?
Types 2
51
What types of hypersensitivity reaction causes Poststreptococcal glomerulonephritis?
Type 3
52
What types of hypersensitivity reaction causes Acute hemolytic transfusion reactions
Type 2
53
What types of hypersensitivity reaction causes Guillain-Barre Syndrome?
Type 4
54
What types of hypersensitivity reaction causes graft-vs-host disease?
Type 4
55
What types of hypersensitivity reaction causes Serum Sickness
Type 3
56
What types of hypersensitivity reaction causes PPD (test for M. tuberculosis)
Type 4
57
What types of hypersensitivity reaction causes contact dermatitis?
Type 4
58
What types of hypersensitivity reaction causes Rheumatic fecer
Type 2
59
What types of hypersensitivity reaction causes Goodpastures Syndrome?
Type 2
60
What types of hypersensitivity reaction causes Bullous pemphigoid?
Type 2
61
What types of hypersensitivity reaction causes Arthus reaction?
Type 3
62
What types of hypersensitivity reaction causes contact dermatitis?
Type 4
63
What types of hypersensitivity reaction causes pemphigus vulgarism?
Type 2
64
Describe the pathogenesis of an allergic reaction to blood transfusion
Type 1 hypersensitivity
Reaction against plasma proteins in the transfused blood
Presentation: urticaria, pruiritus, wheezing, fever
65
Describe the pathogenesis of an anaphylactic reaction to blood transfusion
Severe allergic reaction
IgA-def individuals must receive blood products that lack IgA
Presentation: dyspnea, bronchospasm, hypotension, respiratory arrest, shock
66
Describe the pathogenesis of febrile nonhemolytic transfusion reactions
Type 2 hypersensitivity reaction
Host antibodies against donor HLA antigens and leukocytes
Presentation: Fever, HA, chills, flushing
67
Describe the pathogenesis of an acute hemolytic transfusion reaction
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Type 2 hypersensitivity
Intravascular hemolysis (ABO bloog gourp incompatible) or extravascular hemolysis (host antibody reaction against foreign antigen on donor RBCs)
Presentation: fever, hypotension, tachypnea, tachycardia, flank pain, hemoglobinemia (intravascular), jaundice (extravascular hemolysis)
```
68
What disorder is associated with Anti-ach receptor antibody?
Myasthenia gravis
69
What disorder is associated with Anti-basement membrane antibody?
Goodpastures syndrome
70
What disorder is associated with Anti-cardiolipin, lupus anticoagulant antibody?
SLE, antiphospholipid syndrome
71
What disorder is associated with Anticentromere antibody?
Limited scleroderma (CREST syndrome)
72
What disorder is associated with Anti-dsDNA, anti-Smith antibody?
SLE
73
What disorder is associated with Anti-glutamate decarboxylase antibody?
Type 1 Diabetes Mellitus
74
What disorder is associated with Anti-hemidesmosome antibody?
bollous pemphigoid
75
What disorder is associated with antihistone antibody?
drug-induced lupus
76
What disorder is associated with Anti-jo-1, anti-SRP, Anti-MI-2 antibody?
Polymyositis, dermatomyositis
77
What disorder is associated with antimicrosomal, anti-thyroglobulin antibody
hashimoto thyroiditis
78
What disorder is associated with animitochondrial antibody?
primary biliary cirrhosis
79
What disorder is associated with antinuclear antibodies
SLE, nonspecific
80
What disorder is associated with anti-Scl-70 (anti-DNA topoisomerase 1)
scleroderma (diffuse)
81
What disorder is associated with anti-smooth muscle antibody?
autoimmune hepatitis
82
What disorder is associated with anti-sea, anti-ssb (anti-Ro, anti-La) antibody?
Sjogren syndrome
83
What disorder is associated with Anti-TSH receptor antibody?
graves disease
84
What disorder is associated with Anti-U1 RNP (ribonucleoprotein) antibody?
mixed connective tissue disease
85
What disorder is associated with c-ANCA (PR-3 ANCA) antibody?
Granulomatosis with polyangiitis (Wegener)
86
What disorder is associated with IgA antiendomysia, Iga anti-tissue transglutaminase antibody?
celiac disease
87
What disorder is associated with p - ANCA (MPO-ANCA) antibody?
Microscopic polyangiitis, Churg-Strauss syndrome
88
What disorder is associated with rheumatoid factor (antibody most commonly IgM, specific to IgG Fc region), Anti-CCP antibody
Rheumatoid arthritis
89
What bacterial infection will you likely get if you are missing T cells?
sepsis
90
What bacterial infections are you likely to contract if you are missing B cells? (There are 7)
```
SHiNE SKiS
Strep pneumonia
H. influenza type B
N. meningitidis
E. coli
Salmonella
Klebsiella pneumonia
group B Strep
```
91
What bacterial infections are you likely to get if you have NO granulocytes?
Staphylococcus: Burkholderia cepacia, Serratia, Nocardia
92
What bacterial infections are you likely to get if you are lacking compliment (immune deficiency)?
Neisseria (no membrane attack complex aka MAC)
93
What viral infection are you likely to get if you are missing T cells (immunodeficiency)?
CMV, EBV, VZV, chronic infection with reps/GI viruses
94
What viral infections are you likely to get if you are missing B cells (immunodeficiency)?
```
Enteroviral encephalitis
Polio virus (live vaccine contraindicated)
```
95
What fungal infections are you likely to get if you are deficient in T cells?
Candida
| PCP
96
What fungal/paracidic infections are you likely to get if you are deficient in B cells?
GI giardiasis (no IgA)
97
What fungal/parasite infections are you likely to get if you are deficient in granulocytes?
Candida
| Aspergillus
98
B-cell deficiencies tend to produce recurrent ________ infections.
Whereas, T- cell deficiencies produce more _________ and ________ infections
B-cell deficiencies tend to produce recurrent BACTERIAL infections
Whereas, T- cell deficiencies produce more FUNGAL and VIRAL infections
99
List 3 immune deficiencies that are B-cell linked
1. X-linked (Bruton) agammaglobulinemia
2. Selective IgA deficiency
3. Common variable immunodeficiency
100
List 4 immune deficiencies that are T-cell linked
1. Thymic aplasia (DiGeorge's syndrome)
2. IL-12 receptor deficiency
3. Autosoma dominant hyper-IgE syndrome (Job syndrome)
4. Chronic mucocutaneous candidasis
101
What is the most common primary immunodeficiency?
Selective IgA def
102
Describe the defect associated with X-linked (Bruton) agammaglobulinemia (immunodeficiency)
Defect in BTK, a tyrosine kinase gene - no B cell matuartion. X-linked recessive (increased in boys)
103
Describe the presentation of X-linked (Bruton) agammaglobulinemia (immunodeficiency)
Recurrent bacterial and enteroviral infections after 6 months (decreased material IgG).
104
Describe the presentation of Selective IgA deficiency (immunodeficiency)
Majority asymptomatic. Can see airway and GI infections, Autoimmune disease, Atropy, Anaphylaxis to IgA containing products
105
Describe the defect seen in Common Variable Immunodeficiency (immunodeficiency)
Defect in B-cell differentiation. Many causes
106
Describe the presentation of Common Variable Immunodeficiency (immunodeficiency)
Can be acquired in 20s-30s; increased risk of autoimmune disease, bronchiectasis, lymphoma, sinopulmonary infections
107
Describe the defect associated with Thymic aplasia (DiGeorge's syndrome) (immunodeficiency)
22q11 deletion; failure to develop 3rd and 4th pharyngeal pouches --> absent thymus and parathyroids
108
Describe the clinical presentation of Thymic aplasia (DeGeorge Syndrome) (immunodeficiency)
```
Tetany (hypocalcemia)
Recurrent viral/fungal infections (T-Cell deficiency)
Conotruncal abnormalities (e.g. tetralogy of Fallot, truncus arteriosus)
```
109
Describe the defect associated with IL-12 receptor deficiency (immunodeficiency)
Decreased Th1 response.
| Autosomal recessive
110
Describe the clinical presentation of IL-12 receptor deficiency (immunodeficiency)
Disseminated mycobacterial and final infections;
| may present after administration of BCG vaccine
111
Describe the defect associated with Autosomal dominant hyper-IgE syndrome (Job Syndrome) (immunodeficiency)
Deficiency of Th17 cells due to STAT3 mutation --> impaired rectruitement of neutrophils to sites of infection
112
Describe the clinical presentation of Autosomal dominant hyper IgE syndrome (Job Syndrome) (immunodeficiency)
FATED: Coarse Facies, Cold (non inflammed) stphylococcal, Abscesses, retained primary Teeth, increase IgE, Dermatologic problems (eczema).
113
Describe the defect associated with Chronic mucocuteneous candidiasis (immunodeficiency)
T cell dysfunction. Many causes
114
Descirbe the clinical presentation of Chronic mucocutaneous candidiasis (immunodeficiency)
Non-invassive Candida albicans infections of the skin and mucous membranes
115
List 4 immunodeficiencies that result from EITHER B and/or T cells disorders
1. Severe combined imminodeficiency (SCID)
2. Ataxia-telangiectasia
3. Hyper-IgM syndrome
4. Wiskott-Aldrich syndrome
116
Describe the defect associate with SCID (sever combines immunodef)
Several types including defective IL-2R gamma chain (most common, X-linked), adenosine deaminase deficiency (autosomal recessive)
117
Describe the clinical presentation of SCID (immunodeficiency)
Failure to thrive, chronic diarrhea, thrush. Recurrent viral, bacterial, fungal, and protozoal infections.
118
What is the treatment for SCID? (immunodeficiency)
Bone marrow transplant (no concern for rejection)
119
Describe the defect associated with Ataxia-telangiectasia (immunodeficiency)
Defects in ATM gene --> DNA double strand breaks --> cell cycle arrest
120
Describe the clinical presentation of Ataxia-telangiectasia (immunodeficiency)
Triad: cerebellar defects (ataxia), spider antgiomas (telangiectasis), IgA deficiency
121
Describe the defect associated with Hyper-IgM syndrome (immunodeficiency)
Most commonly due to defective CD40L on Th cells = class switching defect; X-linked recessive
122
Describe the clinical presentation of Hyper IgM syndrome (immunodeficiency)
Severe pyogenis infections early in life; opportunistic infection with Pneumocystitis, Cryptosporidium, CMV
123
Describe the defects associate withe Wiskott-Aldrich syndrome (immunodeficiency)
Mutations in WAS gene (X-linked recessive); T cells unable to reorganize actin cytoskeleton
124
Describe the clinical presentation associated with Wiskott-Aldrich syndrome
WATER: Wiscott-Aldrich; Thrombocytopenic purpura, Eczema, Reccurent infections. Increased risk of autoimmune disease and malignancy
125
List 3 immunodeficiencies that are linked to phagocyte dysfunction
1. Leukocyte adhesion def (type 1)
2. Chediak-Higashi syndrome
3. Chronic granulomatous disease
126
Describe the defect associated with Leukoadhesion deficiency (type 1) (immunodeficiency)
Defect in LFA-1 integrin (CD18) protein on phagocyte; impaired migration and chemotaxis; autosomal recessive
127
Describe the clinical presentation of Leukoadhesion deficiency (type 1) (immunodeficiency)
Recurrent bacterial skin and mucosal infections, absent pus formation, impaired wound healing, delayed separation of umbilical cord (>30 days).
128
Describe the defects associated with Chediak-Higashi syndrome (immunodeficiency)
Defect in lysosomal traffecking regulator gene (LYST). Microtubule dysfunction in phagosome-lysosome fusion; autosomal recessive.
129
Describe the clinical presentation of Chediak-Higashi syndrome (immunodeficiency)
Recurrent pyogenic infection by staphylococci and streptococci, partial albinism, peripheral neuropathy, progressive neuro-degeneration, infiltrative lymphohistocytosis
130
Describe the defects associated with Chronic granulomatous disease
Defect of NADPA oxidase --> decrease reactive oxygen species (e.g., superoxide) and absent respiratory burst in neutrophils; X-linked recessive
131
Describe the clinical presentation of Chronic granulomatous disease
increased susceptibility to catalase positive organisms ( acronym = PLACESS)
Pseudomonas, Listeria, Asperillus, Candida, E. Coli, S. aureus, Serratia
132
Where do we attain AUTOGRAPHS?
from self
133
Where do we attain SYNERGEIC GRAFTS?
from identical twin or clone
134
Where do we attain ALLORAPHS?
from non-indentical individual of same species
135
Where do we attain XENOGRAPHS?
from different species
136
List the 4 types of transplant rejections and their related speed.
1. Hyper-actute - within minutes
2. Acute - weeks to months
3. Chronic - months to years
4. Graft-versus-host-disease - varies
137
Describe the pathogenesis of hyper acute transplant rejection.
Pre-existing recipient antibodies react to donor antigen (type 2 reaction), activate complement.
138
Describe the pathogenesis of acute transplant rejection
Cellular: CTLs actuated against donor MHCs
Humoral: similar to hyper acute, except antibodies develop after transplant
139
Describe the pathogenesis of chronic transplant rejection
Recipient T cells perceive donor T MHC as recipient MHC and react against donor antigens presented.
Both cellular and hum oral components
140
Describe the pathogenesis of graft-vs-host disease
Grafted immuno-compentent T cells proliferate in the immunocompromised host and reject host cells with "foreign" proteins --> severe organ dysfunction
