Usmle Immuno-2 Flashcards
(150 cards)
2
Q
What type of hypersensitivity reaction is seen in Erythroblastosis Fetalis?
A
Type II
3
Q
What type of hypersensitivity reaction is seen in Rheumatic Fever?
A
Type II
4
Q
What type of hypersensitivity reaction is seen in Goodpastures?
A
Type II
5
Q
What type of hypersensitivity reaction is seen in Bullous pemphigoid?
A
Type II
6
Q
What type of hypersensitivity reaction is seen in Pemphigus vulgaris?
A
Type II
7
Q
What type of hypersensitivity reaction is seen in Grave’s disease?
A
Type II
8
Q
What type of hypersensitivity reaction is seen in Myasthenia Gravis?
A
Type II
9
Q
What type of hypersensitivity reaction is seen in SLE?
A
Type III
10
Q
What type of hypersensitivity reaction is seen in RA?
A
Type III
11
Q
What type of hypersensitivity reaction is seen in polyarteritis nodosum?
A
Type III
12
Q
What type of hypersensitivity reaction is seen in Poststreptococcal GN?
A
Type III
13
Q
What type of hypersensitivity reaction is seen in Serum Sickness?
A
Type III
14
Q
What type of hypersensitivity reaction is seen in Arthus Reactions (swelling and inflammation following tetanus vaccine?)
A
Type III
15
Q
What type of hypersensitivity reaction is seen in Hypersensitivity pneumonitis? (AKA farmer’s Lung)
A
Type III
16
Q
What type of hypersensitivity reaction is seen in Type I DM?
A
Type IV
17
Q
What type of hypersensitivity reaction is seen in MS?
A
Type IV
18
Q
What type of hypersensitivity reaction is seen in Guillain-Barre?
A
Type IV
19
Q
What type of hypersensitivity reaction is seen in Hashimoto’s Thyroiditis?
A
Type IV
20
Q
What type of hypersensitivity reaction is seen in Graft-v-Host disease?
A
Type IV
21
Q
What type of hypersensitivity reaction is seen in PPD reactions?
A
Type IV
22
Q
What type of hypersensitivity reaction is seen in Contact dermatitis with poison ivy/nickel?
A
Type IV
23
Q
What lymph nodes would drain the Upper limb or lateral breast?
A
Axillary
24
Q
What lymph nodes would drain the Stomach?
A
Celiac
25
Q
What lymph nodes would drain the duodenum and jejunum?
A
Superior mesenteric
26
What lymph nodes would drain the Sigmoid Colon?
Colic LNs to the inferior mesenteric
27
What lymph nodes would drain the Lower rectum and area above the pectinate line?
Internal iliac
28
What lymph nodes would drain the Anal canal below the pectinate line?
Superficial inguinal
29
What lymph nodes would drain the Testes?
Para-aortic AKA retroperitoneal
30
What lymph nodes would drain the Scrotum?
Superficial inguinal
31
What lymph nodes would drain the Superficial thigh?
Superficial inguinal
32
What lymph nodes would drain the lateral side of the dorsum of the foot?
Popliteal
33
What ultimately drains the right arm and right half of the head?
The right lymphatic duct
34
What drains the left side of the upper body and everything below the diaphragm?
The thoracic duct
35
What region of the LN contains the HEVs?
Paracortex
36
In what condition would you see an enlarged paracortex? Absent paracortex?
Enlarged--> viral or fungal infection
| Absent--> DiGeorges
37
What part of the medulla of LNs is packed with plasma cells?
The medullary cords
38
What is the function of the medullary sinuses within LNs??
Communicate with efferent lymphatics.... They contain reticular cells and macrophages.
39
From what does the Thymus develop?
The third pharyngeal pouch
40
What is found within the medulla of the thymus?
Mature T-cells and epithelial reticular cells
| HASSALLS corpuscles
41
Where within the thymus does MHC restriction (positive selection) and negative selection if autoreactive occur?
Positive selection occurs in the cortex...
| Negative selection occurs in the medulla
42
What are three manifestations of a splenectomy on a peripheral blood smear?
Howell-Jolly bodies
Target Cells
Thrombocytosis
43
What can occur if there is a splenic dysfunction?
Decrease IgM leads to
Decreased compliment activation leads to
Decreased C3b opsonization leads to
Increased susceptibility to encapsulated bacteria
44
What is one of the main function of macrophages in the spleen?
Removal of encapsulated bacteria
45
What are the sinusoids of the spleen?
Vascular channels within the red pulp with a fenestrated basement membrane...Macrophages are found nearby
46
What are the main components of the innate immune system?
```
Neutrophils
Macrophages
Dendritic Cells
NK cells
Complement--- fast, nonspecific and no memory
```
47
Thrombopoietin is used to treat?
Thrombocytopenia
48
Oprelvekin (IL-11) is used to treat?
Thrombocytopenia
49
Gamma interferon is used to treat?
Chronic Granulomatous Disease
50
Beta interferon is used to treat?
MS
51
Alpha interferon is used to treat?
Hep B and C
Kaposi sarcoma
Malignant melanoma
52
What is Sargramostim?
Granulocyte macrophage CSF
53
What is Filgrastim?
Granulocyte CSF
54
What is EPO used to treat?
Anemia, esp from renal failure
55
What is Aldesleukin ?
IL-2 analog
56
What is Aldesleukin used to treat?
RCC and Metastatic melanoma
57
What is Graft-v-Host disease?
When grafted immunocompetent T-cells proliferate in an immunocompromised host.
58
What are the major manifestation of G-v-Host disease?
Maculopapular rash
Jaundice
HS megaly
Diarrhea
59
What is responsible for the damage in Chronic transplant rejection?
T-cells and antibody mediated vascular damage---leads to obliterative vascular necrosis.
60
What is the time frame of Chronic Transplant rejection?
Months to years after transplant
61
What cells are responsible for the acute transplant rejection?
T-cells (cytotoxic t cells) reacting against foreign MHCs
62
What is the timeframe for Acute transplant rejection?
Weeks after transplantation.
63
Is acute transplant rejection reversible?
Yes, with cyclosporine or OKT3
64
What is the mechanism of damage in hyperacute transplant rejection?
Antibody mediated damage due to the presence of preformed antidonor antibodies....Occurs within minutes.
65
What cell surface proteins are found on Macrophages?
MHC II
B7
CD 14
CD 40
66
What is the major secretor of IL-1?
Macrophages
67
What is the main function of IL-1?
Fever...causes acute inflammation
Induces chemokine production to recruit leukocytes
Activates endothelium to express adhesion molecules
68
What is IL-2 secreted by?
Th cells
69
What is the function of IL-2?
Stimulates growth of T-cells, helper and cytotoxic
70
What secretes IL-3?
Activated T-cells
71
What is the main function of IL-3?
Supports growth and differentiation of BM stem cells
72
What secretes IL-4?
Th2 cells
73
What is the function of IL-4?
Promotes growth of B-cells and enhances class switching to Ig E (and IgG)
74
What secretes IL-5?
Th2 cells
75
What is the function of IL-5?
Promotes differentiation of B-cells
Promotes production and activation of Eosinophils
Enhances IgA class switching
76
What secrete IL-6?
Th cells and macrophages
77
What is the function of IL-6?
Stimulates production of acute phase reactants and immunoglobulins (pro-inflammatory)
78
What is the function of IL-8?
The major chemotactic agent for neutrophils
79
What secretes IL-10?
Regulatory T-cells
80
What is the function of IL-10?
Inhibits actions of activated T-cells
81
What secretes IL-12?
B cells and macrophages
82
What is the function of IL-12?
Activates NK and Th1 cells
83
What secretes IFN gamma?
Th1 cells
84
What is the function of IFN gamma?
Stimulate macrophages
85
What secretes TNF?
Macrophages
86
What are the functions of TNF?
Mediates septic shock
| Causes leukocyte recruitment and vascular leak.
87
How do you remember the important uses of ILs 1-5?
```
HOT T-Bone stEAk
IL-1=HOT fever
IL-2= T-cells stimulation
IL-3= B-cell stimulation
IL-4= IgE production
Il-5= IgA production
```
88
What are 4 things that lead to antibody diversity?
```
Random recombination of VJD and VJ genes
Random combination of Heavy and Light chians
Addition of nucleotides to DNA via Tdt
Somatic Hypermutation (following Antigen stimulation)
```
89
What is the benefit of opsonization?
The antibody promotes phagocytosis after it has bound antigen
90
What is the benefit of Neutralization?
So many Antibodies have bound a bacteria that it cannot adhere to cell surfaces.
91
What is the benefit of antibodies WRT complement?
IgG activates complement cascade, leading to enhanced opsonization and lysis.
92
What are 4 important things to remember about the Fc portion of an Antibody?
```
It is
Constant
Carboxy terminal of the antibody
Carbohydrate side chains are present
Complement binding occurs here (IgG and IgM)
Determines Isotype
```
93
What are two things important to remember about the Fab region of an antibody?
Determines Idiotype
and
It is the Antigen Binding fragment.
94
What is the function of the variable region of the light and heavy chains?
Recognizes antigens
95
What is the importance of the Fc portion of IgG and IgM?
Fixes complement
96
What two signals are required for B-cell class switching?
1: IL-4, IL-5 or Il-6 signal from Th2 cell
2: CD40 receptor activation by binding CD40L on Th cell
97
What signals are required for Cytotoxic T-cell activation?
1: Endogenously synthesized protein presented on MHC1 recognized by T-cell Receptor on Tc cell
2: IL-2 from Th cell activates Tc cell to kill virus infected cell.
98
What two signals are required for T-helper cell activation?
1: Foreign body must be phagocytosed by APC and the antigen has to be presented to the Th cells TCR via MHC II interaction.
2: Costimulatory signal of B7 on APC interacting with CD 28 on the Th cell---leads to secretion of cytokines by Th cell.
99
What results if you degrade an Ig molecule with Pepsin?
1 divalent Fab molecule that is still able to bind and bridge antigens and it can agglutinate antigens. Gives you a 'cup' that you can hold Pepsi in. Pepsi, Pepsin.
100
What do you get it you degrade an Ig molecule with papain?
3 fragments-- 2 monovalent Fab fragments that cannot agglutinate Ab
and
1 Fc portion
101
What is they underlying structure of an IgM molecule?
It is a pentamer...each section can bind 2 molecules to it has a valence of 10.
102
GM is classic....
IgG and IgM activate classic complement
103
What is the FIRST antigen made to any response?
IgM.. even if it an allergic reaction mediated by IgE, IgM always had to be activated first before the class switch could occur.
104
What is avidity WRT Ig molecules?
It corresponds to the number of antigen binding sites! IgM has the highest avidity, of 10 since it is a pentamer. IgA has the next highest, of 4 since it is bivalent.
105
What is affinity WRT Ig molecules?
The attractiveness between an antigen and the antigen binding site on an Ig molecule... IgG has the highest affinity.
106
Where within the body does class switching between Ig molecules occur?
In the germinal center of secondary lymphoid tissues during an immune response.
107
The secondary immune response to an antigen (the same antigen) is primarily mediated by...
IgG
108
What is somatic hypermutation?
Point mutations in an already rearranged VDJ regions, esp during immune response, as the DNA polymerase does not have time to fix errors.
109
What is the result of somatic hypermutation?
Increased affinity of an Ig for its antigen...Those with point mutations that decreased the affinity cannot bind the antigen and die off anyway.
110
What is the only Ig that can cross the placenta?
IgG
111
What is the Ig with the highest concentration in breast milk and colostrum?
IgA
112
Where is IgA synthesized?
In the submucosa
113
What are two cytokines needed to switch to IgA?
TGF-Beta
| IL-5
114
What is the major benefit of the secretory component of IgA?
It binds the dimer, holding it together and protecting it from degradative enzymes in the mucosa.
115
How does IgA get into the mucosa?
It binds via its J-chain holding the dimer together to the Poly Ig receptor in the mucosa. This PolyIG receptor becomes the secretory component later on.
116
What are the two cytokines that are used to class switch to IgE?
IL-4
| Il-13
117
Which Ig causes mast cell degranulation?
Ig-E
118
What are the two major Complement anaphalatoxins?
C3a and C5a---they can both bind mast cells and cause degranulation without involving IgE
119
What is the major constituent of complement that allows for removal of immune complexes?
C3b
120
What is the major difference between the alternative and classical complement pathway?
Alternative is Completely innate and does not require antibody mediation to become activated
121
What are two ways a cytotoxic T cell can kill a target cell?
Either through Fas-Fas ligand interactions which releases TNF. When this binds the TNF receptor on the target cell it triggers Apoptosis
OR
CD8 and MHC1 interaction leads to the release of granules with perforin and toxic substances that degrade the cell.
122
NK cells cannot specifically bind antigen, so how to they know which cells to target??
They look for cells that do not have MHC I expressed (happens in virally infected cells due to masking or downregulation to evade Tc cells)
123
What is the main Ig that facilitate ADCC, antibody dependent cellular cytotoxicity?
IgG---can bind cells that express foreign cell surface proteins and then bind via Fc portion to receptors on NK cells
124
What is the one time IgG is not the Ig mediating Antibody dependent cellular cytotoxicity?
IgE can do it IN A PARASITIC infection
125
Look at the last 5 minutes of the cell mediated effector mechanisms chapter in Kap....
And vaccines at 6 minutes into the immunocompromised section ...Good flow diagram
126
What is an example of natural passive immunity?
Placental IgG transport or colostrum transport of IgA leading to immunity
127
What is an example of Natural active immunity?
The hard way...getting an infection and having your body mount an immune response.
128
What are examples of active artificial immunity?
All vaccinations...Hep B
Polio..
MMR...
129
What types of immunity do live attenuated vaccines bestow?
Humoral and cellular BUT they can revert to virulent strains
130
What types of immunity do Killed vaccines bestow?
Only Humoral, but they are stable and cannot revert
131
Who should NOT be administered a live attenuated vaccine?
Immunocompromised, their close contacts
or
Pregnant women
132
Which vaccines have been killed?
```
RIP Always
Rabies
Influenza
Polio (SalK)--K=Killed
Hep A
```
133
What are two examples of recombinant vaccines?
HBV---The antigen is recombinant HbsAg
and
HPV types 6, 11, 16 and 18
134
What are the live attenuated vaccines?
```
MMR
Sabin Polio
VZV
Smallpox
Yellow Fever
```
135
What is the underlying mechanism behind interferon use?
It puts uninfected cells in an antiviral state...They induce production of ribonuclease that inhibits viral protein synthesis by degrading viral mRNA.
136
Main function of interferon Alpha and Beta?
Inhibit viral protein synthesis
137
Main function of interferon Gamma?
Increases MHC I and MHC II expression and antigen presentation in cells
138
What is the effect of interferons on NK cells?
Activates them to kill virus-infected cells
139
Main function of the MAC?
Cytolysis by punching holes in cell membranes.
140
What does deficiency of C1 esterase inhibitor lead to?
Hereditary angioedema due to inability to turn of complement....leads to massive inflammation at mucosal surfaces
141
What does C3 deficiency lead to?
Severe recurrent pyogenic infections esp in sinus and URT.
| Increases the susceptibility to type III hypersensitivity reactions as C3b is not around to clear immune complexes
142
What does deficiency of the MAC or any component of it lead to?
Increased Neisseria infections.
143
What does the deficiency of DAF (decay accelerating factor) lead to? (DAF being absent due to a defect in a GPI linkage)
Complement mediated lysis of RBCs and paroxysmal nocturnal hemoglobinuria
144
What is the general function of C1 esterase inhibitor and DAF?
Prevention of complement activation on self cells
145
Number 1 vaccine not given to pregnant women?
MMR (Or VZV)
146
What are three vaccines not given to ppl with egg allergies?
MMR
Yellow Fever
Influenza
147
What is the only Ig useful in diagnosing infections in infants?
IgM....IgG and IgA could have come from the placenta or breast milk
148
Name two component vaccines
HPV and Hep B (surface antigen)
149
What is the purpose of giving an adjuvant along with a vaccine?
Allows for a longer persistence of the Antigen in the body, so it can make Abs to it instead of just clearing it.
150
What is the only thing the USMLE could give you on a question that would lead you to think Myeloperoxidase deficiency is the answer?
Inability to make hypochlorite...otherwise, no symptoms
151
Rx for Selective IgA deficiency?
Antibiotics, but do NOT give Igs, as they might cross react and cause anaphylaxis.
