Immunology Unit I Flashcards
1
Q
What are the central lymphoid organs?
A
Where lymphocytes develop:
bone marrow and thymus
2
Q
What are the peripheral lymphoid organs?
A
Where mature cells are organized to trap and respond to foreign invaders..
- lymph nodes
- spleen
- Peyer’s patches and mesenteric lymph nodes of the gut
- tonsils
- adenoids.
3
Q
What cells are derived from monocytes?
A
macrophages and microglia (in the brain)
4
Q
What is the liquid equivalent/circulating equivalent to a mast cell?
A
basophil
5
Q
What do mast and basophil cells both contain?
A
histamine
6
Q
In adults what is the normal white blood cell count?
A
4,500-10,500 per microL of blood
7
Q
What is the main job of eosinophils?
A
To kill parasites
8
Q
What is the differential percentage in a normal adult?
A
Neutrophils 40-50% Eosinophils 1-4% Basophils .5-1% Monocytes 2-8% Lymphocytes 20-40%
9
Q
What cell is the bridge between innate and adaptive immunity?
A
Dendritic cells
10
Q
What is an immunogen?
A
An antibody that can trigger an immune response
11
Q
What is a tolergen?
A
From of antigen that does not trigger an immune response and if given an immoform of antigen you also want have an immune response.
Think allergies.
12
Q
Which antibody class has a J chain?
A
IgA and IgM
13
Q
Which antibody class has a secretory component?
A
IgA
14
Q
Which antibody is the largest?
A
IgM (pentamer) MW 900,000
15
Q
Which antibody is the smallest
A
IgG (150,000)
16
Q
What are the five antibody classes?
A
gamma, epsilon, mu, alpha, and delta
17
Q
What is valence?
A
the number of antigenic determinants an antibody
molecule can theoretically bind.
18
Q
What is the valence for IgM?
A
10
19
Q
What is the valence for IgA?
A
4
20
Q
Rank antibody classes by size
A
IgM>IgA>IgE>IgD>IgG
21
Q
Serum vs plasma?
A
Serum is plasma without fibrinogen (no clotting factor)
22
Q
What is the valence F(ab2)?
A
2
23
Q
What is the valence Fab
A
1
24
Q
What is the epitote?
A
The specific part of the antigen that binds to the antibody
25
What is an anti-idiobody?
An antibody specific towards another antibody. Would be incredibly useful for autoimmune disorders
26
How many individual polypeptide chains are there in an IgA molecule?
10 - 4 light chains, 4 heavy chains, 1 J chain, and 1 secretory component.
27
Kappa and lambda chains are on the heavy or light chain?
light chain
28
Is the hinge region part of the light or heavy chain?
Heavy chain
29
What is humoral immunity?
antibody-mediated immunity
30
What is another word for epitote?
antigenic determinant
31
Define precipitation
When the large immune complexes that are formed at or near equivalence (where ratios of antigen
to antibody are optimal) tend to become insoluble and fall out of solution or suspension. Molecules
32
Define agglutination
When the precipitate is formed by cell or cell-sized
| particles.
33
What is immunodiffusion>
When you have an antigen well and antibody well both meet in the middle to form and antigen-antibody complex and precipitate out and you will see that line of precipitate on an agar plate.
34
What is the only antibody to be made by the fetus?
IgM
35
Which antibody class passes the human placenta from mother to fetus?
IgG
36
What is the plasma half-life of IgG?
3 weeks
37
Which antibody class is the first line of immunological defense against invading organisms in the gut?
IgA - remember it got that secretory component!
38
What is the role of IgE?
its Fc end binds to a corresponding receptor on mast cells and basophils, forming a trigger for these histamine-loaded cells
**Important for resistance to PARASITES
39
What is the complement system?
a large number of proteins, similar to the blood clotting system in that each exists in an inactive form, and when the first is activated the rest follow in a sort of cascade.
40
Innate immunity vs adaptive?
Adaptive involves antibodies
41
What is the activation order for the classical complement pathway?
C1q->C4 -> 2 -> 3 -> 5 -> 6 -> 7 -> 8 -> 9
42
What is the activation order for the alternative complement pathway?
C3 -> 5 -> 6 -> 7 -> 8 -> 9
43
What is the activation order for the Lectin complement pathway?
MBP --> C4 -> 2 -> 3 -> 5 -> 6 -> 7 -> 8 -> 9
44
What complement component is responsible for lysis?
C9 activation
45
What complement component is responsible for opsonization?
Phagocytes have C3b and the IgG Fc receptors
46
What complement component is responsible for chemotaxis?
C5a recruits phagocytes/neutrophils
47
What complement component is responsible for anaphylatoxis?
C3a C4a and C5a trigger the release of histamine from mast cells or basophils
48
What is a toxoid?
a toxin that has been turned into a harmless toxoid, but retains its immunogenicity
49
What genetic segments make up the variable heavy chain domain?
V, D, and J
50
What genetic segments make up the variable light domain?
V and J
51
Which enzymes do the recombination of antibody and T cell receptor DNA?
RAG recombinases
52
A single mature B cell starts by making what antibodies?
IgM and IgD
53
What is cross reactivity?
The tendency of one antibody to react with more than one
| antigen
54
Is clonal selection darwanian or lamarckian?
Darwanian
55
Describe GERM LINE VERSUS SOMATIC MUTATION
d, a lot of our diversity is in the germ line (that is, in the individual V, D, and J segments you’re born with). Even more diversity is also generated by variable (“sloppy”) V/J and V/D joining that generates N regions.
Both!
56
Describe the "N” region
exonucleases for chewing away a few nucleotides after the DNA is cut but before two gene segments (D to J, V to
DJ) are joined. Second, for adding a few nucleotides as well, an enzyme called terminal deoxynucleotidyl transferase, TdT and is RANDOM
57
How many light and heavy chains are synthesized by one B cell?
Only one light chain (either kappa or lambda of its 4 choices) and one heavy chain (of its two choices)
58
Explain hypermutable
each time a B cell divides after antigenic stimulation there is a good chance that one of the daughters will make a slightly different antibody.
59
Explain class switching
A single mature B cell starts by making both IgM and IgD, which it puts into its membrane as receptors. Later it may switch to making IgG, IgE, or IgA.
*** the V domain stays the same but the C region of the H chain changes.
60
What is the Bursa of Fabricius?
The bursa is located at the hind end of the gut of birds. Where B cells in birds mature. There is no equivalent in humans. B cells are made in bone marrow
61
What is the difference between an immature and mature B cell?
Immature B cell on has surface IgM (sIgM)
| mature B cells has surface IgM AND IgD
62
How are anti-self B cells prevented?
If an Immature B cell is anti-self it is likely to encounter self while in the bone marrow, thus the B cell either makes a NEW receptor OR triggers apoptosis
63
When does a baby start to produce its own IgG?
about 12 weeks after birth
64
Where do T cells carry out their development?
The Bone Marrow, Thymus, and Peripheral Lymphoid Organs
65
What triggers a B cell to undergo class switching?
T cell
66
Why are the last three weeks of pregnancy most important?
That is when the most amount IgG is being pumped across the placenta to the baby.
39 weeks is ideal because of this reason!
67
When are babies most susceptible to infections?
Between 4 and 7 months
68
What are the three things innate immunity responds to?
Foreign molecular structures called pathogen-associated molecular patterns (PAMP)
- Stress or damage indicator molecules expressed by body cells, called damage-associated molecular patterns (DAMP);
- The absence of certain normal cell surface molecules, this recognition is done by NK cells.
69
What's one of the main Pattern Recognition Receptors? (PRR)
Toll-like receptors
70
TLR4 binds to what?
lipopolysaccharides
71
TLR2 binds to what?
petidoglycan
72
TLR3 binds to what?
double stranded RNA
73
What transcription factors is the mother of all inflammation?
NF-kB
74
What is the role of a B cell?
B cells protect the extracellular spaces of the body—the tissue fluids, blood, secretions—by releasing antibody into these fluids
75
What is the role of the T cell
Survey the surfaces of the body’s cells, looking for ones that have ingested antigens,
have parasites within them, or are dangerously changed or mutated.
76
What are lymphokines?
cytokines made by a lymphocyte
77
What are do B cells and T cells secrete?
B cells secrete antibodies
| T cells secrete lymphkines
78
What is a fully differentiated B cell?
plasma cell
79
What is the role of IgE?
designed to attach to mast cells in tissues and causes the release of histamines.
Think allergies and parasites here!
80
What is Type I immunopathology?
immediate hypersensitivity in patients who make too much
| IgE to an environmental antigen, which is often innocuous like a pollen or food.
81
What is Type II immunopathology?
autoimmunity, due to antibodies which can react against self.
82
What is Type III immunopathology?
whenever someone makes antibody against a soluble
| antigen
83
Type IV immunopathology
T-cell mediated
84
Warm vs Cold autoimmune hemolytic anemias?
Warm AIHAs are mediated by IgG while cold AIHAs are mediated by activation of complement.
85
The primary cell type in a germinal center in a lymph node follicle in the cortex is:
B cells
86
Where is the germinal center in a lymph node?
Within the cortex
87
What molecule is chemotactic for polymorphonuclear neutrophils (PMNs)?
C5a
88
What are the most abundant white cell in the
| peripheral blood?
Neutrophils
89
From 2 years to 8 years of age what are the most abundant white cell in the peripheral blood?
lymphocytes
