Day 2.2 Immuno Flashcards
1
Q
LN
Upper limb, lateral breast
A
Axillary LN
2
Q
LN
Stomach
A
Celiac LN
3
Q
LN
Duodenum, jejunum
A
Superior mesenteric LN
4
Q
LN
Sigmoid colon
A
Colic –> Inferior mesenteric LN
5
Q
LN
Rectum (lower part), anal canal above pectinate line
A
Internal iliac LN
6
Q
LN
Anal canal below pectinate line
A
Superficial inguinal LN
7
Q
LN
Testes
A
Superficial and deep plexuses –> para-aortic LN
8
Q
LN
Scrotum
A
Superficial inguinal LN
9
Q
LN
Thigh (superficial)
A
Superficial inguinal LN
10
Q
LN
Lateral side of dorsum of foot
A
Popliteal LN
11
Q
What does the right lymphatic duct drain?
A
Right arm and right half of head
So if you obstruct R lymphatic duct, will get non-pitting edema of R arm and R head
12
Q
What does the thoracic duct drain?
A
Everything except the R arm and R head (which are drained by the R lymphatic duct)
13
Q
Where does the thoracic duct enter back into circulation?
A
Jn of L. Subclavian in the IJV
14
Q
IL-2
A
T cell stimulator
Anti-IL2 drugs will shut down immune system
15
Q
IL-10
A
Inhibits T cells and Macrophages
16
Q
IFN-gamma
A
Stimulates macrophages
17
Q
Il-4 and IL-5
A
Stimulates B cells
18
Q
What are the components of the adaptive immune system?
A
T cells
B cells
Ab
19
Q
Fns of lymph node
A
non-specific filtration by macrophages
storage and activation of B and T cells
Ab production
20
Q
LN Follicles
A
Site B cell localization and proliferation.
Follicles are in outer cortex.
21
Q
Where are Tcells found in LN?
A
Paracortex (bt follicles and medulla)
22
Q
How do T and B cells enter the LN from the blood?
A
Through high endothelial venules in the paracortex of the LN
23
Q
Where is the paracortex located w/in the LN?
A
Region of cortex, bt the follicles and the medulla.
24
Q
Which part of the LN becomes enlarged during extreme cellular immune response?
A
Paracortex
25
Which part of the LN is underdeveloped in pts with DiGeorge syndrome?
The paracortex.
DiGeorge = no Tcells
Paracortex houses Tcells
No Tcells = sml paracortex
26
Where are the plasma cells located in the LN?
Medullary cords (medulla)
27
Where are macrophages located in the LN?
Medullary sinuses (medulla)
28
Where are Tcells located in the spleen?
PALS periartierial lymphatic sheath
| and in the red pulp
29
Where are Bcells located in the spleen?
Follicles and white pulp.
30
T cell location in LN, Spleen
LN: Paracortex
Spleen: PALS
31
B cell location in LN, Spleen
LN: Follicle
Spleen: Follicle
32
What is the fn of macrophages in the spleen?
Remove encapuslated bacteria
| SKHNSB
33
Which pts are more susceptible to encapsulated bacteria? What can be done to help them?
Asplenic pts
| Vaccinate them.
34
What vaccines do asplenic pts need?
Pneuomvax (pneumococcus, against S. pneumonia)
HiB
Meningiococcal
35
Why are asplenic/splenic dysfn pts susceptible to encapsulated bacteria?
They have decreased IgM, which means decreased complement activation, which means decreased C3b opsonization, which means increased susceptibility to encapsulated.
36
Why are pts asplenic?
```
Sickle cell (auto-infarct of spleen)
Trauma
```
37
What is the Rx for hereditary spherocytosis?
Remove spleen (this is one option)
38
Post-splenectomy, what do RBCs look like?
More Howell-Jolly bodies (RBCs with nuclear remnants)
More target cells (excess mbr relative to amt of Hb)
Also will have thrombocytosis (high PLT count)
39
What is the classic presentation of infarction on CT?
Wedge/triangular lesion, with point/apex toward center of body and base of triangle toward outside/body wall
40
Why does lymph fluid have a milky appearance?
It is high in Chylomicrons, high in Triglycerides
41
Thymus is site of what?
Tcell differentiation and maturation.
42
Where does the thymus come from embryologically?
Epithelium of 3rd brachial pouches (IMP!)
43
What is the structure of the thymus?
Inner medulla, outer cortex.
| Medulla = middle = mature Tcells
44
Where does Tcell selection occur in the thymus?
Corticomedullary jn.
| Tcells start as immature in cortex and mature as they go inward to medulla. Undergo selection as they mature.
45
What is positive and negative selection of Tcells in the thymus
```
Positive = MHC restriction
Negative = nonreactive to self
```
46
Where do Tcells and Bcells mature?
Tcells- thymus
| Bcells- bone marrow
47
What cells make up the innate immune system?
```
Neutrophils
Macrophages
Dendritic cells (APCs- present to neutrophils and macrophages)
NK cells
Complement.
Each cell can do many different jobs.
```
48
What is the only lymphocyte that is part of the innate immune system?
NK cells.
| The other lymphocytes (Tcells, Bcells) are part of the adaptive immune system.
49
Innate vs Adaptive: which is fast and non-specific?
Innate.
| Innate is also germline-encoded, whereas adaptive is not, it is learned.
50
Vaccines affect which, innate or adaptive?
Adaptive
| Adaptive is the only system with memory.
51
How do NK cells kill virus-infected cells?
They use perforin and granzymes to cause apoptosis (in both virally infected and in tumor cells)
52
Which cytokines enhance NK cells?
IL-12
IFN-alpha
IFN-beta
53
Virus-infected cells release IFNs. What do IFNs signal?
They induce NK cells
| They induce neighbor cells of the virus-infected cell to inhibit viral protein synthesis
54
What signals induce NK cells to kill?
Non-specific activation signals on the target cell, and/or absence of MHC-I on cell surface. MHC-I is found on most every cell in the body, so no MHC-I means it's not self.
55
What are the fns of B cells?
Make Ab
IgG Ab opsonize bacteria and neutralize viruses
IgE Ab mediate Type I HPS allergic rxns
IgG Ab mediate Type II HPS cycotoxic rxns and Type III HPS Immune complex rxns
Ab cause hyperacute organ rejection
56
What are the fns of T cells?
CD4+ Tcells help B cells make Ab
CD4+ Tcells make IFN-gamma, which activates macrophages
CD8+ Tcells kill virus-infected cells directly (the are cytotoxic)
Responsible for Type IV HPS- cell-mediated delayed HPS
Responsible for acute and chronic organ/allograft rejection
57
After positive selection of Tcells in the cortex of the thymus, what cells are left?
Start as CD4+ CD8+ and after pos selection are either CD4+ 8- or CD4- 8+
Depending on whether they bind MHC-I (CD8+) or MHC-II (CD4+)
58
Which happens first, pos selection or neg selection of Tcells?
Positive, then negative
59
What is negative selection?
Tcells that react to self are apoptosed. Occurs at corticomedullary jn
60
What is the fn of CD8+ cells?
```
Cytotoxic Tcells
Kills 3 things:
Virus-infected cells
Neoplastic cells
Donor graft cells
Similar to the NK cells of the innate immune system (NK cells are also lymphocytes)
```
61
How do cytotoxic CD8+ cells kill?
By apoptosis.
They rls cytotoxic granules which have perforin and granzyme.
Perforin helps perforate and deliver content of granules into cells.
Granzyme is a serine protease that activates apop w/in cell.
62
Cytotoxic CD8+ and NK cells are similar, but they differ with regards to MHC-I recognition. How?
NK cells recognize the absence of MHC-I, and kill cells with out it, since they are non-self.
Cytotoxic CD8+ cells use their CD8+ to recognize MHC-I on virally infected cells.
63
Do cytotoxic CD8+ cells cause inflammation?
No they cause apoptosis.
64
What cytokine induces CD4+ Thelper cells to become Th1?
IL-12
| IL-12 is produced by virally infected cells
65
What cytokine induces CD4+ Thelper cells to become Th2?
IL-4
| IL-4 is produced by Th2 cells (pos feedback)
66
What cytokines do CD4+ Th1 cells secrete?
IL-2
| IFN-gamma
67
Which cytokine inhibits Th2 production?
IFN-gamma, secreted by Th1 cells
68
What does IL-2 stimulate?
Tcells (e.g. CD8+ cytotoxic Tcells)
69
What does IFN-gamma stimulate?
Macrophages
| Also inhibits Th2 production.
70
What cytokines does CD4+ Th2 produce?
IL-4
IL-5
IL-10
71
What do IL-4 and IL-5 do?
Stimulate B cells to make Ab (IgE > IgG)
72
What does IL-10 do?
Inhibits Th1 and macrophages
73
What cytokine inhibits Th2 production?
IFN-gamma (secreted by Th1)
74
What cytokine inhibits Th1 production?
IL-10 (secreted by Th2)
75
In general, what kinds of cells do the Th1 and Th2 pathways stimulate?
Th1 - macrophages and Tcells (incl CD8+ cytotoxic Tcells)
| Th2 - B cells. Inhibit Tcell production.
76
How do you identify cell surface proteins (e.g. CD4, CD 19, etc)
By flow cytometry
77
What are the cell-surface proteins on Helper Tcells
```
CD4
TCR
CD28 (binds to B7 on APC)
CD3
CD40L (binds to CD40 on B cells for class switching)
```
78
Cell surf proteins on Cytotoxic Tcells
CD8
TCR
CD3
79
Cell surf proteins on B cells
IgM, IgD
CD19, CD20, CD21 (receptor for EBV)
CD40 (binds to CD40L on Thelpers for B cell class switching)
MHC-II (bc B cells can be APCs)
B7 (bc B cells can be APCs- binds to CD28 on T helper)
80
Cell surf proteins on Macrophages
MHC-II (bc it's APC)
B7 (bc it's APC. binds to CD28 on Thelper)
CD40
CD14, CD16
Receptors for Fc and C3b. (Fc and C3b are opsonins, so macrophages have receptors to recognize them)
81
Cell surf proteins for NK cells
Receptor for MHC-I (all body cells have MHC-I. If not, it's not self, so NK will kill it)
CD16 (binds the Fc of IgG)
CD56
82
Cell surf protein for all cells except mature RBCs
MHC-I
| If no MHC-I, it's not self, so NK will induce apoptosis
83
Cell surf proteins for RBCs, WBCs, Plts
CD55, CD59
| These protect against complement-mediated dmg
84
Hot T-Bone stEAk
```
IL-1 = hot (fever)
IL-2 = T (stim's Tcells)
IL-3 = Bone (stim's bone marrow)
IL-4 = E (stim's IgE production- and also IgG)
IL-5 = A (stim's IgA production- and also eosinophil production)
```
85
What is the first signal in Thelper activation?
The TCR and the CD4 on the Thelper bind to the MHC-II on the APC
86
What is the second signal in Thelper activation?
Co-stimulatory signal:
| CD28 on Thelper binds to B7 on the APC
87
What is the first signal in Cytotoxic Tcell activation?
TCR and CD8 on the cytotoxic Tcell bind to MHC-I on the infected cell. (All body cells have MHC-I, so can be any cell in the body that's infected)
88
What is the second signal in Cytotoxic T cell activation?
A Thelper cell must have already differentiated into Th1, and that Th1 must secrete IL-2.
IL-2 is the second signal which activates the cytotoxic cell to kill the infected cell. (via apop)
89
What is the first signal in B-cell class switching?
IL-4, IL-5, or IL-6 must be secreted from a Th2 cell
90
What is the second signal in Bcell class switching?
CD40 receptor on Bcell must bind to the CD40L on the Thelper cell.
91
What are the two ways macrophages are stimulated by bacterial toxins?
1. Superantigens (S. pyogenes, S. aureus)
| 2. Endotoxins/LPS
92
How do superantigens stimulate macrophages?
S. pyogenes and S. aureus
They cross-link the Beta region of the TCR to the MHC-II on the APC. This results in uncoordinated rls of IFN-gamma from Th1 cells.
IFN-gamma stims macrophages.
Macrophages rls IL-1, IL-6, TNF-alpha
93
How do Endotoxins (LPS) stimulate macrophages?
LPS is on gram neg bacteria.
Directly stim's macrophages by binding to endotoxin receptor CD14 on macrophages.
(Tcells are not involved)
Macrophage = CD14!
94
What is the receptor for endotoxins?
CD14 (on macrophages)
95
What cytokines are rlsd by macrophgs?
IL-1
IL-6
TNF-a
These are the "acute phase cytokines"- they cause fever and increase immune response in general.
also IL-8 and IL-12 are secreted by macrophages.
96
IL-1
IL-1 = Hot
Secreted by macrophgs, causes acute inflam.
Induces chemokine production to recruit leukocytes
Activates endothelium to express adhesion molecules
Endogenous pyrogen.
97
What are the endogenous pyrogens?
IL-1
IL-6
(secreted by macrophages)
98
IL-2
IL-2 = T (Stim's Tcells)
Secreted by Th1 cells.
Stimulates growth of Thelper and cytotoxic Tcells
99
IL-3
IL-3 = Bone (stim's bone marrow)
Secreted by activated Tcells
Supports growth/differentiation of bone marrow stem cells.
Has a fn similar the GM-CSF (which stim's bone marrow stem cells to differentiate)
100
Immunosuppresant drugs often block/antagonize which cytokine?
IL-2
| e.g. Cyclosporine, Tacrolimus (anti-rejection drugs)
101
What are the neutrophilic chemotactic factors?
IL-8
C5a
LTB4 (leukotriene b4)
102
IL-4
```
IL-4 = E
Secreted by Th2 cells
Promotes growth of B cells.
Enhances class switching to IgE and IgG
Causes Th --> Th2 differentiation (pos fdbk)
```
103
IL-5
```
IL-5 = A
Secreted by Th2 cells
Promotes differentiation of B cells
Enhances class switching to IgA
Stim's production and activation of eosinophils
the "mucus' IL
```
104
IL-6
Secreted by Th cells and macrophages.
Stim's production of acute-phase reactants and Igs
Pro-inflammatory
Endogenous pyrogen- causes fever
105
IL-8
Secreted by macrophages
| Mjr chemotactic factor for neutrophils.
106
IL-10
Secreted by Regulatory T Cells.
Inhibits action of activated Tcells!
Activates Th2, inhibits Th1
107
IL-12
Secreted by B cells and macrophages.
Activates NK cells
Causes Th --> Th1 differentiation
108
INF-gamma
Secreted by Th1 cells
Stim's macrophages
Activates Th1, inhibits Th2
Assoc'd w cell immunity- imp for anti-viral, anti-cancer (so helps w cytotoxic Tcells)
109
TNFa
Secreted by macrophages
Acute phase cytokine
Mediates septic shock
Causes leukocyte recruitment and vascular leak.
Generalized inducer of the immune system.
110
What are the anti-TNFa agents?
Etanercept
Infliximab
Adalimumab
111
What are the anti-TNFa agents used for?
Musculoskeletal- used for seroneg HLA-B27 disorders:
PAIR (psoriasis, ankylosing spondylitis, inflam bowel dz, reiters/reactive arthritis)
Also for non-arthritic psoriasis
Also for rheumatic arthritis
112
Which anti-TNFa agent is a TNF decoy receptor?
Etanercept
| EtanerCEPT is a TNF decoy reCEPTor.
113
How does Infliximab work?
Anti-TNF Ab
114
How does Adalimumab work?
It blocks the TNF-receptor on cells by binding directly to it, so that TNF can't bind to them.
115
How does Etanercept work?
It is a decoy receptor for TNF (so TNF binds to it, but nothing happens)
Recombinant form of human TNF receptor.
116
Toxicity of Infliximab?
Predisposes to infections e.g. reactivation of latent TB
| so before giving, do a ppd test
117
Which cytokine has a similar fn to GM-CSF?
IL-3
118
What is the mechanism by which interferons work?
Interferons are proteins that make uninfected cells go into an anti-viral awareness state. They induce the production of a ribonuclease that inhibits viral protein sythesis by degrading viral mRNA, but not host mRNA.
Interferon has three types- alpha, beta, gamma.
Interferon INTERFERes with viruses
119
What are the functions of alpha and beta interferons?
They inhibit viral protein synthesis (viral mRNA)
| They activate NK cells to kill virus-infected cells
120
What is the function of gamma interferons?
They increase MHC-I and MHC-II expression
Increase Ag expression
In all cells
121
When are exogenous interferons given to patients?
alpha interferon: HBV, HCV, Kaposi's sarcoma, leukemias, malignant melanoma
beta interferon: MS
gamma interferon: chronic granulmatous dz (NADPH oxidase deficiency
122
List the recombinant cytokines
```
Aldesleukin (IL-2)
Erythropoetin (epoetin)
Filgrastim (G-CSF)
Sargrastatin (GM-CSF)
alpha interferon
beta interferon
gamma interferon
Oprelvekin (IL-11)
Thrombopoietin
```
123
What is Aldesleukin used for?
Recombinant IL-2
| Used in RCC renal cell carcinoma and metastatic melanoma (skin cancer)
124
What is Erythropoetin (epoetin) used for?
Recombinant cytokine used for anemias, esp in renal failure- chronic kidney dz/dialysis pts, or in chemo.
Give in renal failure bc EPO normally comes from kidneys- if they're failing they're not mkg it.
125
What are Filgrastin and Sargramostim used for?
Fil= G-CSF
Sar= GM-CSF
Recombinant cytokines used for recovery of bone marrow after chemo
126
What is Oprelvekin used for?
Recombinant IL-11
| Used for Thrombocytopenia (stim's plt production in bone marrow)
127
What is Thrombopoetin used for?
Recombinant cytokine
| Used in Thrombocytopenia (stim's plt production in bone marrow)
128
What's the cell-surface receptor for EBV?
CD21 on B cells
129
What is the basic structure of an Ab?
2 heavy chains, 2 light chains.
Held together by disulfide bonds
Fab region binds Ab and is the N-terminal
Fc region binds complement and is the C-terminal
Only one Ab type expressed per B cell.
130
What part of an Ab recognizes Ag?
The Fab part;
| The end of both the heavy and light chain is the "variable" part- V-H and V-L.
131
What parts (Fab, Fc) do the heavy and light chain contribute to?
Heavy makes up both Fc and Fab
| Light is only Fab
132
Which Ab fix complement? What part of the Ab fixes it?
Fc part of IgM and IgG
| IgM is immediate, IgG is delayed
133
Where are disulfide bonds found on Ab's?
```
Disulfide bonds bind:
Heavy and light chains together
Heavy chains to each other
w/in heavy chains
w/in light chains
```
134
For Ab, which end is the N-terminus? Which is the C-terminus?
```
N-terminus = Fab
C-terminus = Fc
```
135
All B cells express only one type of Ab. In what illness are there lots of B cells all expressing the same thing?
Multiple Myeloma (B cell tumor)
136
Fc: C is for...
```
Constant
Complement-binding (IgM and IgG only)
Carboxy terminal
Carbohydrate side chains
and it determines the isotype (IgD, IgE, etc)
```
137
What are the 5 types of heavy chain?
mu, delta, gamma, alpha, epsilon
| IgM, IgD, IgG, IgA, IgE
138
What part of the Ab determines the isotype? (IgA, IgE, etc)
The Fc part
139
What are the 2 types of light chains?
kappa and lambda
| these are functionally the same
140
What is the normal ratio of kappa to lambda light chains in humans? Why is it important?
2 kappa : 1 lambda
| The ratio will be off in proliferative B cell dz like multiple myeloma
141
Using the heavy chain and light chain types, what are the possible ways to make an IgA
2 alpha regions (heavy) and 2 lambda regions (light)
or
2 alpha regions (heavy) and 2 kappa regions (light)
142
What are the 3 jobs of Ab?
Opsonization (promote phagocytosis)
Neutralization (prevents bacterial adherence)
Complement activation (which enhances opsonization and lysis)
143
The TCR is an Ab
That's all.
| Another name for Ab is Ag receptor. Same thing.
144
VDJ recombination: what are the DNA segements?
V = variable
D = diversity
J = joining
They are flanked by RSS (recombination signal sequences) on either side.
145
How is VDJ recombination initiated?
RAG 1 and 2 (recombination activating gene complex). RAG1 and RAG2 recognize the RSS flanking the VDJ.
146
What happens when there is a mutation in RAG1 or RAG2 (in mice)?
They can't initiate VDJ rearrangement, so there is arrest of B cell and T cell devt.
147
What enzyme is responsible for recombination?
Terminal deoxynucelotidyl transferase. It adds nucleotides to DNA during recombination.
148
How is Ab diversity generated?
1. Random recombination of VJ (light chain) or VDJ (heavy chain) genes
2. Random combo of heavy chains with light chains
3. Somatic hypermutation (after Ag stimulation)
4. Addition of nucleotides to DNA during recombination by terminal deoxynucleotidyl transferase
149
Which Ab are on the surface of Bcells?
IgM and IgD
150
How can Bcells which express IgM and IgD on their surfaces differentiate in plasma cells that secrete IgA, IgG, or IgE?
By isotype switching- alternative splicing of mRNA. Mediated by cytokines and CD40L
151
IgG
Main Ab in secondary (delayed) Ag response.
Most abundant Ab
Fixes complement
Crosses placenta (infants get passive immunity)
Opsonizes bacteria, neutralizes bacterial toxins and viruses.
t1/2 = 21 days
152
IgA
Prevents attachment of bacteria and viruses to mucus membranes.
Monomer in circulation, Dimer when secreted.
In secretions (tears, saliva, mucus)
In breastmilk ("colostrum")
Picks up secretory component from epithelial cells before secretion.
153
IgM
Md in primary (immediate) response to Ag.
Fixes complement.
Ag receptor on the surface of Bcells
If on B cells- monomer
Otherwise, pentamer- which allows it to trap free Ag outside of the tsu while humoral response is working
154
IgD
Unclear fn
| On surface of Bcells, also in serum
155
IgE
Binds mast cells and basophils
Cross-links when exposed to allergen, mediates Type I HPS thru rls of inflam mediators (histamine)
Mediates immunity to works by activating Eosinophils
Lowest conc in serum
156
To see if a pt has a recent west nile virus infection, what Ab would you look for?
IgM- this will tell you if pt has a NEW infection. Pt may have IgG Ab which would suggest previous infection.
157
What are thymus-independent Ag?
Ag lacking a peptide component- the can't be presented to Tcells on MHC. They stimulate rls of IgM only, and don't result in immune memory
Ex: LPS from gram-neg; polysaccharide capsular Ag
158
What are the thymus-dependent Ag?
Ag that contain a protein component and there for do induce immune cell memory. Class switching (IgM --> IgG) occurs as a result of direct contact of Bcells w/ Thelper cells (CD40-CD40L interaction) and rls of IL-4, IL-5, and IL-6
Ex: Conjugated H. inflz vaccine
159
What are the two pathways of the complement system?
Classic- activated by Ag-Ab complexes (IgG or IgM with Ag)
Alternative- activated by microbial surfaces (nonspecific activators like endotoxin/LPS)
3rd pathway- Lectin is activated by microbial surfaces; enters classic pathway
160
What are the two primary opsonins in bacterial defense?
IgG
| C3b- aids in clearance of immune complexes
161
How is complement activation of self inhibited?
DAF (decay accelerating factor) (DAF = CD55 + CD59)
| C1 esterase inhibitor
162
Complement: what do C1, C2, C3, C4 do?
Viral neutralization
163
Complement: what does C3b do?
Opsonization. B Binds Bacteria.
| Also clears immune complexes
164
Complement: what do C3a, C5a do?
Anaphylaxis (A= anaphylaxis)
| Also, C5a is a neutrophil chemotactic factor
165
What molecules induce neutrophil chemotaxis?
C5a
LTB4
IL-8
166
Complement: what do C5b-C9 do?
Cytolysis by MAC
167
Deficiency of C1 esterase inhibitor
Causes hereditary angioedema.
| No esterase inhibitor means increased bradykinin, which means angioedema
168
How does C3a cause anaphylaxis?
Stim's mast cells, basophils to rls histamine --> vasodilation and incrsd vasc permb --> fluid leaves vessels and goes to tsu --> decreased BP -->Anaphylaxis
the fluid mvmt also causes edema.
169
Rx for anaphylaxis?
Epinephrine
170
Deficiency of C3
Severe recurrent pyogenic sinus and respi tract infections (esp w Strep pneumo and H.inflz)
Increased susceptibility to Type III HPS rxns, esp glomerulonephritis
171
Deficiency of C5-C9
No MAC --> Neisseria bacteremia (both gonococcal and meningiococcal)
172
Deficiency of DAF (GPI-anchored enz)
Complement-mediated lysis of RBC
| PNH (paroxysmal nocturnal hemoglobinuria)
173
What is PNH
Paroxysmal Nocturnal Hemoglobinuria
No DAF (CD55&59) so RBCs are dmgd and iron spills out --> hemosiderinuria, plus iron-def anemia
Chronic intravascular hemolysis (this causes the hemosiderinuria)
Thrombosis
174
How do you dx PNH?
Ham's Test: do RBCs lyse at low pH? If yes, it's PNH
| Can also do flow cytometry- look for CD55 and CD59 (these are the DAF). If missing, it's PNH.
175
Rx for PNH
Iron and Anticoagulant (warfarin), but ultimately, bone marrow txplt
176
What are the granulomatous diseases? (12)
1. TB (only one with caseating granulomas)
2. Fungal infections (histoplasmosis, blastomycosis)
3. Syphilis (gummas)
4. Leprosy
5. Cat scratch fever (Bartonella)
6. Sarcoidosis
7. Crohn's dz
8. Berylliosis
9. Listeria
10. Foreign bodies (body walls it off)
11. Wegener's granulomatosis
12. Chronic granulomatous dz (NADPH oxidase deficiency)
177
What is anergy?
Self-reactive Tcells become non-reactive without co-stim molecule.
Bcells can also become anergic, but tolerance is less complete than in Tcells.
178
Ex of antigenic variation in bacteria
Salmonella has 2 flagellar variants
Borrelia (relapsing fever)
N. gonorrhea (pilus protein)
179
Ex of antigenic variation in a virus
influenza virus
major = Ag shift
minor chg = Ag drift
180
Ex of antigenic variation in parasites
Trypanosomes have programmed rearrangement
181
What is active immunity?
Induced after exposure to foreign Ag.
Slow onset, long-lasting protection (Bcell memory).
Due to IgG.
182
What is passive immunity?
Immunity from Ab received from another host.
Rapid onset of immunity, but short life-span of Ab (t1/2 = 3 weeks)
Ex IgA in breastmilk.
183
For what exposures are pts given Ab for passive immunity?
Tetanus toxin
Botulinum toxin
HBV
Rabies virus
"To Be Healed Rapidly"
Also, preemies should get RSV Ab in winter months.
All of these should be given in addition to vaccine!
