Immunology Flashcards
(246 cards)
1
Q
Direct pathway of allorecognition
A
Involves intact donor MHC presenting peptide to host T-cells
2
Q
Indirect pathway of allorecognition
A
Refers to the presentation of donor MHC to host T-cells as processed peptides loaded onto host MHC molecules
3
Q
AMR preferentially attacks which renal structures?
A
Peritubular and glomerular capillaries
4
Q
Mixed lymphocyte culture measures?
A
differences in Class II proteins between cells
5
Q
Engraftment with bone marrow stem cells takes how long?
A
median - 21 days
6
Q
Engraftment with PBSC takes how long?
A
median - 14 days
7
Q
Increases in number of mismatches in Host vs Graft direction increases risk of …
A
Graft failure
8
Q
Phase I GVHD
A
Effects of conditioning regimen leads to tissue damage and generation of pro inflammatory cytokines (TNFa and IL-1).
9
Q
Phase II GVHD
A
Donor T cells are activated by host APC. Activated T-cells produce cytokines (IL-2) leading to T-cell expansion
10
Q
Phase III GVHD
A
Cytokine storm with positive feedback loop of cytokine production leads to activation of effector cells (CTLs and NK cells), which produce more pro-inflammatory cytokines (TNFa and IL-1)
11
Q
Increases in the number of mismatches in Graft vs Host direction leads to …
A
GVHD
12
Q
Structure of HLA Class I
A
alpha (heavy) protein chain, with 3 alpha domains, that is noncovalently associated with B-2 micro globulin (light) non-polymorphic protein
13
Q
Structure of HLA Class II
A
2 distinct glycoprotein chains, alpha and beta
14
Q
Recombinant HLA haplotypes occur when?
A
During meiotic cell division of germ cells (chromosomal replication –> X shaped chiasmata –> cross over site –> complementary exchange of genetic material)
15
Q
T-cell mediated rejections preferentially attacks…
A
Tubules and arterial endothelium
16
Q
Cord stem cell transplantation leads to less _____ due to relative immaturity of donor immune system at birth.
A
GVHD
17
Q
Definition of epitope or antigenic determinant
A
minimum structural unit that can be recognized by a B or T-cell receptor
18
Q
HLA gene is located on this chromosome
A
Chrom 6p
19
Q
HLA gene is this many kbp long
A
4,100 kbp
20
Q
HLA has this many loci
A
200
21
Q
HLA is how many aa long
A
300
22
Q
ACD stand for…
A
Acid Citrate Dextrose
23
Q
Anticoagulant sample can be reclassified to remove_____ from plasma and yield _____
A
fibrinogen; serum
24
Q
Anticoagulant of choice for Cellular Assays are ____ and should be stored at RT for no longer than____
A
Na Hep and ACD; 24 hrs
25
Anticoagulant of choice for Cytotoxicity assays are _____ and should be stored at RT for no longer than ______
Na Hep and ACD; 48 hrs
26
Anticoagulant of choice for DNA test is ______
EDTA and ACD
27
Cold storage makes it difficult to ________ for cellular assays
Isolate lymphocytes from other cells
28
Trauma respirator _______ PMNS, hence, lymphocytes
increases
29
Blood samples should be collected at lease _____ hours after last transfusion to avoid typing transfused cells
24
30
Centrifuge blood samples for ...
10 mins at 850 - 1000 G (RCF)
31
Laboratory reports are to be achieved for this many years
2
32
Cytotoxic drugs ____ the number of lymphocytes and their viability.
decreases
33
EDTA stands for
ethylenediaminetetraacetic acid
34
EDTA, Sodium citrate, and sodium oxalate are not recommended for cytotoxicity assays because they act as chelaters that...
remove calcium and interfere with complement activation in CDC assays
35
For long term storage (>72 hrs) serum should be stored at least
70C
36
Fetal calf serum supplies a source of ______ for cells
protein
37
Cells in cellular medium should be should be stored at ___C
4
38
Lymphocyte count _____ with age
decreases
39
Lymphocytes have variability of HLA antigens, particularly
DR antigens
40
Clinical scenarios that lead to increased granulocytes, which can make it difficult to isolate lymphocytes
lymphadenopathy
viral, fungal, protozoan infections
HIV/AIDS
Immunosuppression
41
Lymph nodes are ____% T cells and ____ % B cells
75;25
42
OSHA stands for
Occupational Safety and Health Administration
43
Peripheral blood has ____% T cells and _____% B cells
50-90;5-20
44
Spleen has ____ %T cells and _____% B cells
50;50
45
Steroids _____ HLA antigen expression and _____ the number of granulocytes and platelets
decreases; increases
46
Serum can be stored at 4 - 8C for _____ hrs
<72
47
T cell stimuli for macrophage activation include ____ ligand and _____
CD40; IFN gamma
48
Activation of naive CD8 T-cells requires signal 1, which is ______, and signal 2, which is _______. Signal 2 is only present on ______.
Class I/peptide complex; costimulators/cytokines; professional APCs.
49
Process in which selection by antigen of B cells whose mutated receptors fit the antigen most tightly resulting in differentiation of only those B cells, which make antibodies of high affinity for their cognate antigen
affinity maturation
50
Complement activation pathway that is triggered by microbial surfaces and does not involve antibody
alternative pathway
51
Immunoglobulin heavy and light chains are held together by this
disulfide bonds
52
Best characterized T cell costimulatory pathway and has critical role in regulating T cell activation and tolerance
B7:CD28
53
Phagocytes and dendritic cells respond to signals via
Toll-like receptors
54
APCs bring antigen from tissue to ______ and from blood to _______.
lymph node; spleen
55
communication between T-cells and phagocytes is mediated by cytokines and ___:___ ligand interactions
CD40; CD40
56
chemoattractant cytokine - a small secreted protein which activates G-protein coupled to serpentine receptors
chemokine
57
Complement activation path way that is triggered by antigen-antibody complexes
classical pathway
58
Coreceptor for Helper T cells, cytotoxic T cells, and B cells
CD4, CD8, CD21/CD2
59
CD8 T cells kill cells infected with ______ pathogens
intracellular
60
Ig that mediate complement fixation
IgM, IgG1, IgG3
61
Ig that mediate opsonization
IgG1 and IgG3
62
Ig that mediate placental transfer
IgG2 and IgG4
63
Ig involved in mucosal immunity
IgA1, IgA2, IgM
64
Ig that mediates immediate type hypersensitivity
IgE
65
The ____ ligand on activated T cells delivers growth signal to B cells via ____ ligand on B cells; these along with T cell derived cytokine signals are delivered in germinal centers and contribute to clonal expansion and beginning of isotope switching and somatic mutation
CD40;CD40
66
Heavy chain constant regions are mad up of _____ domains
3 or 4
67
_____ Immune cells reconstitute before _____ immune cells. _______ are there first cells to reconstitute
Innate; adaptive; monocytes
68
Macrophages help stimulate acute inflammation through section of cytokines, mainly _____ and _____
TNF; IL-1
69
IgM tends to bing with _____ affinity to antigen than other isotopes, but its pentameric structure ______ avidity (ability to bind antigen)
lower; increases
70
Activated mast cells release histamine as well as ____
TNFa
71
T cell clonal expansion driven by IL-_ and IL-_ receptor
IL-2; IL-2
72
Th1 CD4 T cell differentiation stimulated by ____ produced by microbe-activated phagocytes. Th1 cell produce _____ and are effector cells that activate _____
IL-12; IFN gamma; macrophages
73
Th2 CD4 T cell differentiation stimulated by _____. Th2 cells produce ____ and ____, which promoted IgE and eosinophil-mediated anti-helminthic responses. Th2 may also down regulate ____ response
IL-4; IL-4; IL-5; Th1
74
Innate recognition components
PAMPs (Pathogen-associated molecular patterns)
75
Complement activation path way induced by MBL bound to target mannans
Lectin pathway
76
Lymph node:
T cells and dendritic cells reside in the ______
B cells reside in the _______
Plasma cells reside in the ______
para-cortex
cortex
medulla
77
_____ is a C1q like protein that can opsonize certain carbohydrate antigens and fix complement and thus helps to initiate signaling for innate immunity.
Mannose binding lectin
78
CD8 T-cell Fas: Fas ligand interaction cand lead to ______ of target cell
apoptosis
79
Granzymes from CD8 T-cells can activate intracellular ______, which can lead to apoptosis
caspases
80
Class I HLA generally bind and present _____ derived peptides to _____ T cells
intracellularly; CD8
81
Class II HLA generally bind and present ____ derived peptides to _____ T cells
extracellularly; CD4
82
Most potent APC
Dendritic cells
83
Naive lymphocytes remain in secondary lymphoid organs (______ and _______) where they search for cognate antigen. They do not track to _______.
spleen/lymph nodes/tissues
84
NK cells can promote inflammation by secretion of ____
IFN gamma
85
Natural killer complex is on chromosome ___
19
86
HLA-E presents peptide derived from _____
HLA-A,-B,-C
87
Number of lymphocytes in humans
100 Billion
88
Positive chemotaxis chemokines
IL-8 and INF
89
Primary lymphoid organs
Bone marrow and thymus
90
Protein degradation occurs mainly in ____ and ______
lysosomes and proteosomes
91
Pattern Recognition Receptors are present on _____ and bind to ______
APCs/PAMPs
92
Th2 cells ______ Th1 mediated functions by secretion of ___,___,___ which inhibit macrophage activation
suppress/IL-4/IL-10/IL-13
93
Th2 cells promote inflammatory actions by secretion of ____ and ____, that are dominated by eosinophils and mast cell for protection against helminths
IL-4/IL-5
94
IL-4 stimulates production of ____ antibodies, which opsonize helminths and bind to ____ cells
IgE/mast
95
IL-5 activates _____, which bind to IgE coated helminth by ___ receptors.
eosinophils/Fc
96
MBL binds ______ forming a complex that start the lectin complement pathway by cleaving C3 and C4
MASPs (MBL associated proteases)
97
Spleen:
T-cells located around _______
B-cells located in _______
Marginal zone, around the PALS, contains the ______
PALS
Primary and secondary lymphoid follicles
APCs
98
T cell activation requires 2 signals:
1. MHC-peptide complex
| 2. Costimulatory signal, such as B7 (w/o this signal T cell will become anergic)
99
T-cell dependent pathways of B-cell activation requires secondary signal by _____ expressed on surface of activated ____ T cells.
CD40/CD4
100
T-cell dependent B-cell activation leads to B-cells that produce _____ affinity antibodies
High
101
T-cell independent B-cell activation does not trigger isotope switching or affinity maturation; thus, antibodies tend to be of _____ class with ____ affinity
IgM/low
102
T-cell independent pathways of B-cell activation requires secondary signal by _____ which respond to ______
Toll like receptors/PAMPs
103
TCR are composed of ____ and ____ chains
alpha and beta
104
Class I groove is approx ____ A long and closed at both ends, thus only accommodates _____ peptides
25/short
105
Portion of class I molecule that interacts with CD8 molecule on cytotoxic T cell
alpha 3 domain
106
Class II group is open-ended and thus can accommodate _____ peptides.
larger
107
Class II pathway is designed to present peptide derived from _____ proteins
extracellular
108
Portion of heavy chain associated with the light chain
VH domain and CH1 domain
109
Portion of the heavy and light chains that are involved in antigen recognition are the _______ ends and are referred to as ______ domains
N-terminal/Variable
110
Size of alpha heavy chain of Class I
40-50 kDa
111
Size of B2-microglobulin
12 kDa
112
Variable domains of TCR alpha and beta chains contribute to ...
antigen binding site
113
Greg cells involved in immunological tolerance and characterized by cell surface expression of ____,____,____
CD4, CD25, FoxP3
114
Fluorescent dye that intercalates between the bases of DNA and RNA
Ethidium bromide
115
Excluding HLA antibodies, a positive AHG T cell crossmatch can be due to ______
macrophage contamination
116
Positive B cell XM does not usually cause hyperacute rejection because
vascular endothelium expresses little class II antigens
117
A ration between ______ for a cuvette spectophotometer indicates that the DNA sample is pure
1.8 - 2.0
118
A typical thermal cycler program fro HLA typing generally has how many cycles?
30
119
Absorbance 260nm/280nm values <1.8 indicate presence of ______
protein and membrane fractions
120
Absorbance 260nm/280nm values >2.0 indicate presence of ______
RNA contamination
121
Mechanism of action of Prograft (tacrolimus)
calcineurin inhibitor --> dephosphorylates NFKb ---> prevents T-cell transcription
122
Mechanism of action of cyclosporine A
calcineurin inhibitor --> dephosphorylates NFKb ---> prevents T-cell transcription
123
Mechanism of action of Cellcept (mycophenolate)
relatively selective inhibition of DNA replication in T cells and B cells by inhibiting de novo synthesis of purines
124
Mechanism of action of Imuran (azathioprine)
elatively selective inhibition of DNA replication in T cells and B cells by inhibiting de novo synthesis of purines
125
Mechanism of action of OKT3
monoclonal antibody targeted at the CD3 receptor
126
Positive control serum must be heat-inactivated to ...
destroy any inherent complement activity
127
ASHI minimum labeling requirements
Identifier and date of collection
128
B5 splits
B51, B52
129
B12 splits
B44, B45
130
B14 splits
B64, B65
131
B15 splits
B62, B63, B75, B76, B77
132
B16 splits
B38, B39
133
B17 splits
B57, B58
134
B21 splits
B49, B50
135
B22 splits
B54, B55, B56
136
B40 splits
B60, B61
137
B70 splits
B71, B72
138
Best characterized T cell costimulatory pathway
B7:CD28/CTLA-4
139
B2 microglobulin encoded on chromosome _____
15
140
physiologic pH
7.2 - 7.6
141
Bw4 antigens
B51, B52, B44, B13, B27, B63, B77 ,B38, B57, B58, B49, B47, B37, B53, B59
142
BW6 antigens
B7, B8, B64, B65, B75, B76, B39, B18, B50, B54, B55, B56, B35, B60, B61, B41, B42, B45, B48, B67, B71, B72, B73, B7801, B8101
143
communication between lymphocytes and phagocytes to induce phagocyte effect functions is medicated by cytokines and ______
CD40 ligand: CD4 interactions
144
Hemacytometer cell count calculation
cells/ml = average count per large square (of which there are 9 large squares, each with surface area of 1mm^2) x dilution factor x 10^4
145
Channel shift in flow cytometry XM is determined by examining which histogram (axes)
FITC vs cell number
146
Chi-square test is used to...
assess significance o concordant and discordant reactions
147
The corrector for B cells
CD21/CD2
148
PCR inhibitors (4)
hemoglobin, heparin, ethanol, bleach
149
Temperature at which DNA denatures into single strands
94 - 96C
150
Temperature at which annealing of primers occurs
45 - 65C
151
Temperature at which replication/extension of amplicon occurs
72C
152
DNA sequences are always written from ____ to ____
5'/3'
153
EDTA inhibits PCR by...
inhibiting Taq via sequestration of MgCl2
154
Excessive dNTP concentration can lead to ______ and/or ______
mistakes in extension (incorporating the wrong base)/inhibition of Taq
155
Triton X-100 (detergent) lyses _____ in order to release _____
cell membrane/nuclei
156
Tween-20 (detergent) lyses _____
nuclei
157
Proteinase K destroys _______ bound to DNA. Proteinase K is destroyed by _______ which is important as it can degrade DNA polymerase
proteins/high temp (90C)
158
Frozen lymphocyte trays expire within _______
6 months
159
HLA DM is involved in _______
Loading antigen onto HLA-DR molecules
160
How can granulocytes in cell preparations interfere with crossmatch assay?
They can take up staining dyes resulting in false positive reactions.
161
Molarity =
moles of solute/liters of diluent
162
NaOH will do what do DNA?
denature
163
CD4 T cell generation of ______ helps drive class switching to IgE
IL-4
164
CD4 T cell generation of ______ helps drive class switching to IgA
TGF-beta
165
Besides frost bite liquid Nitrogen presents what other major danger to personnel
suffocation
166
Viability of negative control well in serological typing should be _____ %.
>80
167
Polyacrylamide gels are used to separate fragments of DNA of _____ -______ base pairs
5 - 500 (small fragments)
168
Coding/sense primer
5'
169
non-coding/non-sense primer
3'
170
Primer length
20 - 30 bps
171
Water is categorized by type based on ______
resistivity
172
Endonucleases are
restriction enzymes
173
Purine bases
A and G
174
Pyrimidine bases
C and T
175
______ temp and ______ salt concentration favors higher stringency
High/low
176
Cytokine that plays critical role in the up-regulation of HLA-DR molecules
IFN-gamma
177
Degeneracy of the genetic code refers to ....
The redundancy exhibited as the multiplicity of three-base pair codon combinations that specify an amino acid.
178
Size of probe that would be expected to have a single target the haploid genome
16bp
179
The ______ prevents internal self-peptides from binding to HLA class II during HLA biosynthesis
invariant chain
180
______ divalent cations in ______ are essential in catalysis of _______. However, to much of it can ______ amplification
Mg/MgCl2/Taq polymerase/inhibit
181
Calculation for melting temperature (Tm) for short piece of DNA
Tm= (4 X GC pairs) + (2 x AT pairs)
182
Interaction btwn antibody and antigen is mediated by _______, _______, _______, and _______ (types of interactions/bonds)
hydrogen bonds/hydrophobic interactions, electrostatic interactions, Van der Waals interactions
183
Portion of heavy chain that is associated with light chain are the _______
N-terminal end (Variable domains)
184
Primary humoral immune response usually occurs within _______ days of stimulation
5 - 10
185
As the speed of centrifuged is doubled, the RCF is ________
quadrupled
186
0.9% normal saline is _____ g or NaCl in ______ ml of water
9g/1000ml
187
Greg cells are characterized by these surface markers (3)
CD4, CD25, FoxP3
188
Tris-EDTA buffer, pH 8.0 is good for long-term DNA storage at 40C, as the high pH ______ and the EDTA _____
inhibits acid hydrolysis/ inhibits nucleases
189
Bw4 antigens that are known to cross react with Bw6 sera
```
B27
B37
B44
B49
B51
B52
B53
B57
B58
```
190
Macrophages can be separated via uptake of _____ _____
iron fillings
191
CD25 AKA
IL-2 receptor
192
Mechanism of action of Sirolimus, aka rapamycin
Mtor inhibitor
193
Chemokines are ligands for ______ coupled receptors
G-protein
194
Cytokines are ligands for ______ coupled receptors
JAK-STAT
195
M1 macrophages are more _______ and promote _____ responses
proinflammatory/Th1
196
M2a macrophages are stimulated by _______ and involved in resistance to _______ infections
IL-4/parasitic
197
M2b/c are more ________ and release ______ and ______
anti-inflmmatory/IL-10/TGF-B
198
vital dyes stain ______ cells (examples include _____)
injured;dead/ethidium bromide, eosin-Y
199
supravital dyes stain ______ cells (examples included _____)
viable;alive/acridine orange and CFDA
200
NKG2A and NKG2B are _____ and have associated ______ sequences
inhibitory/ITIM
201
NKG2C, NKG2E, and NKG2H are ______ and associate with the ______ accessory molecule
DAP12
202
NKG2 molecules are generally associated with ______ surface receptor, except ______ which forms a homodimer and is usually associated with _______ accessory molecule; it is a potent activator that can overcome inhibitory signals from the same target cell
CD94 (short cytoplasmic tail)/NKG2D/DAP10
203
Frame work KIR genes (4)
3DL3
3DP1
2DL4
3DL2
204
KIR2D receptors have ____ extracellular domains and bind _____ ligands.
2/HLA-C (residues 77 & 80)
205
KIR3D receptors have ____ extracellular domains and bind _____ ligands
3/HLA-Bw4 (residues 77-83)
206
Group 2 HLA-C alleles, including _____ (4), are ligands for KIR _____
C2, C4, C5, C6
| KIR2DL1
207
Group 1 HLA-C alleles, including _____ (4), are ligands for KIR____ and KIR____
C1, C3, C7, C8
| KIR2DL2 and KIR2DL3
208
HLA Class II Synthesis - has ______ chain in ER for stabilization. This chain is cleaved in the acidified endosome and the _____ molecule remains to stabilize the molecule until peptide is loaded
invariant/CLIP
209
Class I peptides are ______ (~____ - ______ aa long)
short/8-10
210
Class II peptides are ______ (~____ - ______ aa long)
long/up to 30
211
Positive selection occurs in the _____ of the thymus
cortex
212
Negative selection occurs in the _____ of the thymus
medulla
213
B2 microglobulin encoded on this chromosome
15
214
HLA-DO and -DM help to regulate this function
peptide insertion
215
DR2 splits
DR15 and DR16
216
DR3 splits
DR17 and DR18
217
DR5 splits
DR11 and DR12
218
DR6 splits
DR13 and DR14
219
celiac disease HLA association
DQB1*02:01 with DQA1*05:01 (DQ2.5)
220
Type I DM HLA association
DQB1*02:01 and DQB*03:02
221
narcolepsy HLA association
DQB1*06:02
222
______ binds to MHC Class II and releases _____ fragment to allow peptide to bind
HLA-DM/CLIP
223
_____ inhibits HLA-DM to expand the repertoire of peptides presented by Class II molecules. It allows for ____ peptides to be presented
HLA-DO/self
224
Class I heavy chain is stabilized by ______ until B2 micro globulin binds
calnexin
225
Peptide is delivered by _____
TAP
226
Peptide-loading complex consists of ______ (5)
TAP, tapasin, PDI, ERp57, calreticulin
227
Bw4 sequence
TLLR/IALR
228
Aw4 sequence
IALR
229
Bw6 sequence
NLRG
230
These three Bw6 alleles have 76V instead of 76Q aa sequence difference
B*46:01, 73:01, 18:06
231
KIR encoded on this chromosome
19
232
HLA-E presents _____
self peptide derived from leader sequences of HLA-A, B, C
233
HLA-F can exist without stabilization from ______ for a while and guide itself to the surface to pull in exogenous protein. This protein can then be loaded onto Class I or II. HLA-F can also donate its ______ to stabilize Class I
B2 microglobulin/B2 microglobulin
234
HLA-G is expressed on _______ and provides protection during pregnancy from NK cells as placenta does not express Class Ia. HLA-G also binds KIR_____ within the _____ to inhibit the _____ cell.
fetal trophoblasts/2DL4/endosome/NK
235
MICA and MIC B do not have ______ or ______ like Class Ia molecules. They can act as a ligands for ______, which activates NK cells
peptide/B2 microglobulin/NKG2D
236
CD1 present the ______ portion of ______ to T-cells
hydrophillic/lipids
237
Human hemochromatosis HLA association
A*03:01
238
ERp57/PDI responsible for binding of ______ to ______
tapasin/TAP
239
______ removes ______ terminus of protein to yield peptide of 8-10 aa for Class I molecular groove
ERAP/N
240
Piptide - HLA interactions is primarily through _____
H-bonds
241
INF __, ___, ____ can induce Class I expression, but only IFN ____ can induce Class II
alpha, beta, gamma/gamma
242
_____ is the transcription activator for Class I
NLRC5
243
_____ is the transcription activator for Class II
CIITA
244
HLA association with carbamazepine and phenytoin hypersensitivity
B*15:02
245
HLA association with allopurinol hypersensitivity
B*58:01
246
HLA association with abacavir and flucloxacillin hypersensitivity
B*57:01
