Immunology Flashcards Preview

Cumulative Exam Review - SG > Immunology > Flashcards

Flashcards in Immunology Deck (73):
1

What makes up the cell wall of gram positive bacteria?

Techoic acid
Thick peptidoglycan

2

What makes up the cell wall of gram negative bacteria?

LPS in outer membrane
Thin peptidoglycan

3

Intracellular bacteria are primarily taken care of by what type of immune response?

They are shielded from humoral antibodies, so they are eliminated by the cellular immune response

4

Tissue damage after infection with intracellular bacteria is caused by the host response, in what form does this damage occur?

Inflammation

5

What general type of bacterial toxin is a component of the bacterial cell wall?

Endotoxin

6

What general type of bacterial toxin is actively secreted by the bacteria?

Exotoxin

7

Immune system cells are derived from pluripotent hematopoeitic stem cells in the bone marrow. These can then differentiate into what two progenitor cell types?

Myeloid
Lymphoid

8

Neutrophils, basophils/mast cells, eosinophils, erythrocytes, monocytes, and platelets all come from what progenitor cell lineage?

Myeloid

9

B lymphocytes, T lymphocytes, and Natural Killer cells all come from which cell progenitor lineage?

Lymphoid

10

What innate immune cell performs the effector function of phagocytosis and digestion of microbes?

Neutrophils

11

What innate immune cell performs the effector function of allergic reactions AND defense against helminths?

Eosinophils

12

What 2 innate immune cell types are involved in allergic reactions?

Basophils
Mast cells

13

What is the circulating macrophage precursor?

Monocytes

14

What innate immune cells performs phagocytosis and digestion of microbes AND antigen presentation?

Macrophages

15

Mannose (mannan)
LPS
Peptidoglycan
Bacterial CpG DNA
dsRNA

The above are all considered ________, which aid in recognition by innate immunity

PAMPs

16

What are the ligands for the TLR1:TLR2 heterodimer?

Lipopeptides
GPI

17

What are the ligands for the TLR2:TLR6 heterodimer?

Lipotechoic acid
Zymosan

18

What is the ligand for TLR3?

dsRNA

19

What is the ligand for the TLR4:TLR4 homodimer?

LPS

20

What is the ligand for TLR5?

Flagellin

21

What is the ligand for TLR7?

ssRNA

22

What is the ligand for TLR8?

ssRNA

23

What is the ligand for TLR9?

Unmethylated CpG-rich DNA

24

What are the 5 signs/symptoms of inflammation?

Heat
Redness
Swelling
Pain
Loss of function

25

What innate immune cell type is the first to arrive at the site of tissue damage? The activation of these leads to respiratory bursts and release of granules to control bacterial growth

Neutrophils

26

Which interleukin is primarily responsible for NK proliferation?

IL-15

27

Which interleukin is primarily responsible for synthesis of acute phase proteins in the liver?

IL-6

28

Type I interferons like IFN-alpha and IFN-beta are involved in response against what type of pathogen?

Viral

29

IFN-gamma is most important in defense against what type of pathogen?

Bacterial

30

Which interleukin is of primary importance for generating fever?

IL-1

31

Which cytokine is of primary importance for activation of endothelial cells?

TNF

32

What type of mediator in the immune system consists of several circulating plasma proteins that can be induced rapidly by cytokines after infection?

Acute-phase proteins

Examples: MBL, CRP

33

The complement system may be activated by 3 different pathways, all of which lead to the production of _____, which intiates activation of the ____ component - leading to formation of the membrane attack complex

C3b; C5

34

Of the properties of adaptive immunity, _________ refers to the ability to recognize and respond to many different pathogens

Specificity

35

Of the properties of adaptive immunity, _________ refers to enhanced responses to recurrent or persistent infections

Memory

36

Of the properties of adaptive immunity, _________ refers to the ability to keep pace with rapidly proliferating pathogens

Clonal expansion

37

Of the properties of adaptive immunity, _________ refers to responses to distinct microbes that are optimized for effective defense

Specialization

38

Of the properties of adaptive immunity, _________ refers to prevention of injurious immune response against host cells and tissues

Nonreactivity to self Ags

39

Th1 cells produce _____ that activates macrophages to destroy microbes

IFN-y

40

T cells only recognize protein Ags, but B cells can recognize a range of Ags. What type of Ags do B cells recognize?

Proteins, polysaccharides, lipids, and nucleic acids

41

What are the only APCs capable of presenting to naive T cells?

Dendritic cells

42

T-cell receptor complexes consist of 2 Ag-binding chains: _______ and _______. TCRs are identical in each individual T cell. Although the TCR has a short cytoplasmic tail, signaling occurs via _______, which is always expressed with the TCR. Each T helper cell expresses _____ which is required for interaction with the APCs. CTLs express the co-receptor molecule _______.

Alpha; beta
CD3
CD4
CD8

43

What are the 3 professional APCs?

Dendritic cells
Macrophages
B cells

44

Ag processing for class II MHCs:

____________ Ags are processed in the lysosomes of professional APCs. The alpha and beta chains of MHC II are produced in the _________. A specialized invariant chain ________ prevents binding of endogenous peptides in endosomes. Endosomes fuse with lysosomes. Enzymes within the lysosome degrade CLIP, enabling binding of exogenous peptide Ags into MHC II.

Exogenous
ER
CLIP

45

Class II MHCs allow presentation to what type of T cells?

CD4+ T helper cells

46

Ag processing for Class I MHCs:

Microbial ___________ are degraded by proteasomes to peptides. Degraded peptides are carried into the ______ by transporters of antigenic peptides (TAP1 and TAP2). Peptides are loaded into the MHC class I complex. The complex is routed through the _______ to the plasma membrane.

Proteins
RER
Golgi

47

Class I MHCs present processed peptides to what type of T cell?

CD8+ CTLs

48

Which of the following are not properties of MHC molecules?

A. Co-dominant expression
B. Polymorphic genes
C. Class II expression on all nucleated cells
D. Class I expression on all nucleated cells
E. All of the above are properties of MHC molecules

C.

Class II are only expressed on professional APCs

49

For full activation of CD4+ T cells, at least ______ TCRs must bind the Ag simultaneously. Cross-linking of those leads to signaling and activation. _____ and ______ are signaling subunits noncovalently attached to the TCR.

Two
CD3; zeta chains

50

The first signal in activation of CD4+ T cells is the TCR complex recognizing Ag, but this is not enough to activate the T cell. What is the second signal?

Co-stimulation via B7-CD28

51

After activation by Ag and costimulation, naive CD4+ T cells may differentiate into specific subsets of Th1 and Th2 cells. The fate is controlled by cytokines. ______ produced by microbe-activated macrophages and DCs stimulates differentation into Th1 CD4+ cells.

IL-12

52

If there is no IL-12, the T cells produce ______ that stimualtes differentation into Th2 cells

IL-4

53

Compare Th1 to Th2 in terms of what type of immunity they provide

Th1 = cell-mediated

Th2 = Ab-mediated

54

What T-cell specific cytokine is responsible for T cell growth stimulation?

IL-2

55

What T-cell specific cytokine is responsible for B cell switching to IgE?

IL-4

56

What T-cell specific cytokine is responsible for activation of eosinophils?

IL-5

57

What T-cell specific cytokine is responsible for activation of macrophages?

IFN-y

58

What T-cell specific cytokine is responsible for inhibition of T cell activation?

TGF-B

59

B cells can produce various classes of Abs, but only after Ag-activated B cell is helped by activated CD4+ T helper cells and becomes a _______ cell

Plasma

60

Where does T and B cell interaction occur?

In a local lymph node

61

During T cell mediated activation of a B cell:

The B cell presents Ag to helper T cell --> Helper T cell is activated and begins expressing ______, secretes cytokines --> B cells are activated by ______ engagement and cytokines --> B cell proliferation and differentiation

CD40L
CD40

62

In terms of Ab structure and functional domains, light chains come in two varieties, called ______ and ________. The different heavy chains correspond to their class and are given greek letters; these correspond to what FIVE Ab classes???

Kappa; lambda

IgG
IgM
IgA
IgD
IgE

63

An Ab is a tetramer of 2 pairs of identical heavy and light chains. Both heavy and light chain molecules have variable and constant domains.

Which region confers Ag recognition?

Which region interacts with cell surface receptors?

Which region confers flexibility?

Which region specifies specific biological activity?

Ag recognition = Variable region aka F(ab')2

Cell surface receptors = Constant region aka Fc

Flexibility = Hinge domain

Biological activity = Fc fragment

64

Which Ab isotype has 4 subclasses? Which Ab isotype has 2 subclasses?

IgG has 4: IgG1-4

IgA has 2: IgA1-2

65

Describe each Ab isotype in terms of its number of subunits

IgG = monomer
IgM = pentamer
IgA = dimer
IgD = monomer
IgE = monomer

66

What is the principle effector function of IgM?

Complement activation

67

What is the principle effector function of IgG?

Fc receptor-dependent phagocyte responses, complement activation, neonatal immunity (placental transfer)

68

What is the principle effector function of IgE?

Immunity against helminths, mast cell degranulation

69

What is the principle effector function of IgA?

Mucosal immunity

70

What cytokine is associated with production of IgG?

IFN-y

71

What cytokine is associated with production of IgE?

IL-4

72

What cytokine is associated with production of IgA?

TGF-B

73

The gamma-globulin fraction of serum is primarily composed of 3 Ab isotypes: _______, ________, and ______.

______ is present at low concentrations.

Only traces of ______ are found in circulation

IgG, IgA, IgM

IgE

IgD