Principle of Immunity

Question 1

The human immune response to an invading
pathogen can consist of three phases which are

Answer 1

Phase I: innate - immediate immunity (natural barriers of immune system)
Phase II: Innate - induced
Phase III: adaptive

Question 2

what are the natural barriers of the immediate innate immune response? Name 3

Answer 2

▪ Mucociliary escalator
▪ Skin (including sebum)
▪ Lacrimal apparatus (tear system)
▪ Saliva
▪ Gastric juice
▪ Urine
▪ Normal microbiota

Question 3

name 3 granulocytes

Answer 3

basophil
neutrophil
eosinophil

Question 4

myeloid stem cells in bone marrow convert into what in the blood?

Answer 4

platelets
basophil
neutrophil
eosinophil
monocytes
mast cell precursor
dendritic cell

Question 5

erythroid stem cells in bone marrow convert into what in the blood?

Answer 5

erythrocytes

Question 6

lymphoid stem cells in bone marrow convert into what in the blood?

Answer 6

NK cells
B cells
T cells

Question 7

cells of innate immunity in blood

Answer 7

basophil, neutrophil, esoinophil, monocyte, NK cell

Question 8

cells of innate immunity in tissues

Answer 8

macrophage, mast cell, dendritic cell, NK cell

Question 9

what cells are in involved in adaptive response to immunity

Answer 9

B cells, T cells

Question 10

main function of macrophages

Answer 10

▪ Engulfing and digesting microorganisms
▪ Clearing out debris and dead cells
▪ Stimulating other cells involved in immune function

Question 11

PAMPs (Pathogen-associated Molecular Patterns) are recognised by what

Answer 11

PAPMs are recognized by PRRs (Pattern Recognition Receptors)

Question 12

what are PAMPs

Answer 12

PAMPs is the term given to the components of pathogens (including proteins, lipopolysaccharides, carbohydrates, lipids and distinct nucleic acid genomes) that permit them to be discriminated from host components.

[they tend to have repetitive structures so can’t be discriminated from the host components]

Question 13

what are DAMPs (Damage-associated Molecular Patterns)

Answer 13

Cell-derived components that are released due to trauma, ischemia, and tissue damage, either in the absence or presence
of pathogenic infection

DAMPs are recognized by particular PRR

Question 14

TLRs (Toll-Like Receptors) are expressed by?

Answer 14

Macrophages, Dendritic cells, B cells,
NK cells, & certain epithelial cells.

Question 15

The structure of a TLR contains:

Answer 15

1. Ectodomain that can recognize various ligands
2. Transmembrane domain
3. TIR domain

Question 16

which TLRs are on the cell surface

Answer 16

TLR1, TLR2, TLR4, TLR5, TLR6 and TLR10 are located on the
cell surface

Question 17

which TLRs can be expressed in the endosomal compartments

Answer 17

TLR3, TLR7, TLR8, & TLR9 can be expressed in the endosomal
compartments

Question 18

Macrophages and DCs produce inflammatory cytokines
including (name 3):

Answer 18

• IL-1
• IL-6
• TNF-alpha
• The chemokine, CXCL8 (IL-8)

Question 19

what does TNF-alpha do to the endothelium

Answer 19

TNF-alpha makes local endothelium leaky

Question 20

The acute inflammatory response mediated by?

Answer 20

The acute inflammatory response mediated by the release of pro-inflammatory cytokines
[these pro-inflammatory cytokines are produced from macrophages and dendritic cells]

Question 21

C3b is a crucial component of the complement system, and it’s formed by the cleavage of?

Answer 21

C3 - which acts as an opsonin [tagging pathogens and other targets for phagocytosis,
and is essential for both innate and adaptive immunity]

Question 22

what is opsonization

Answer 22

Process whereby soluble proteins (such as
immunoglobulins or complement
components) bind to the surface
pathogens and make them susceptible to
ingestion by phagocytes

-> enhancement of phagocytosis by coating bacteria with C3b

this process allows for efficient phagocytosis