Introduction to Immunology

Question 1

The types of cells which originate from Pluripotential stem cells?

Answer 1

Myeloid Progenitor Cells

Lymphoid Progenitor Cells

Question 2

List the Myeloid Progenitor Cells

Answer 2

Naught - Neutrophils
Monkeys - Monocytes
Eat - Eosinophils
Banana’s - Basophils

Question 3

List the Lymphoid progenitor cells

Answer 3

T- Cells

B- Cells

NK( Natural Killer) Cells

Question 4

The different types of of Immune Systems

Answer 4

Innate Immunity

Adaptive Immunity

(Humoral) Immunity

Question 5

Innate Immunity

Answer 5

Characteristics:
Antigen nonspecific
Rapid Response(Minutes- hours)
No Immunological memory

Immune Components:
Natural Barriers(Skin , mucous membranes)
Phagocytes and NK Cells
Soluble mediators: Complement

Question 6

Adaptive Immunity

Answer 6

Characteristics:
Antigen specific
Slow Response(Days)
Immunological memory

Immune Components:
Lymphocytes
Antigen Recognition( B and T-Cell receptors)
Secreted molecules: Antibody

Question 7

Functional categories of Cytokines

Answer 7

1. Cytokines that Facilitate Innate Immune Responses
2. Cytokines that Induce Differentiation of Distinct T-Cell Lineages
3. Cytokines that Promote Inflammatory Responses
4. Cytokines that Affect Leukocyte Movement
5. Cytokines that Stimulate Haematopoiesis

Question 8

Cytokines that facilitate Innate Immune Responses

Answer 8

– IL-1, IL-6, TNF-α, interferon-α (IFN- α), and IFN-β

– Fever, etc.

Question 9

Cytokines that induce Differentiation of Distinct T-Cell

Lineages

Answer 9

– TH1 lineage: Interferon-γ, TNF-α

– TH2 lineage: IL-4, IL-10, TGFβ

Question 10

Cytokines that promote Inflammatory Responses

Answer 10

– IL-6, IL-10, IL-23, and TNF-α

Question 11

Cytokines that affect Leukocyte Movement

Answer 11

Chemokines function in concert with inflammatory

mediators to regulate the expression and conformation of cell adhesion molecules.

Question 12

Cytokines that stimulate Haematopoiesis

Answer 12

Colony-stimulating factors (CSFs): Granulocyte CSF:
neutrophils↑

Erythropoietin (EPO)

Question 13

Ways in which the innate complement system can be activated

Answer 13

Classical Pathway- Antibody

Lectin Pathway- Carbohydrate

Alternative Pathway- C3b deposits on pathogen surface

Question 14

The major activities generated by the innate complement system pathways

Answer 14

1. Opsonins/ Opsonification
2. Anaphylatoxins-Induction of inflammation
3. Killing of pathogens

Question 15

Draw the structure of an Immunoglobulin

Answer 15

Light chains

Heavy Chains

Areas of glycosylation

Antigen binding site

Complement binding site

Fc binding site

Question 16

Name the types of Immunoglobulins

Answer 16

G. A. M. E. D:

IgG

IgA

IgM

IgE

IgD

Question 17

IgG

Answer 17

Size + 
Monomers 1
[Serum] +++
[Secretions] -
1st response- Nothing
2nd response ++
Crosses placenta: Yes

Question 18

IgM

Answer 18

Size +++++
Monomers 5
[Serum] ++
[Secretions] -
On B cells: Nothing
Allergy:  Nothing
1st response ++
2nd response: Nothing
Crosses placenta: No

Question 19

IgA

Answer 19

Size ++
Monomers 2
[Serum] -
[Secretions] ++
On B cells: Nothing
Allergy: Nothing
1st response: Nothing
2nd response +
Crosses placenta: Nope

Question 20

IgE

Answer 20

Size +
Monomers 1
[Serum] +
[Secretions] -
On B cells: No
Allergy +++
1st response Nothing
2nd response +
Crosses placenta: No

Question 21

IgD

Answer 21

Size +
Monomers 1
[Serum] -
[Secretions] -
On B cells ++
Allergy: Nothing
1st response: Nothing
2nd response +
Crosses placenta: No

Question 22

Draw a lymph node structure

Answer 22

Capsule
Subcapsular sinus
Trabecula
Cortex
Paracortex( T cells)
Primary lymphoid follicle
Lymphoid secondary follicle(B cells)
Antigen presenting Cells
Medulla
Medullary Sinus
Afferent lymphatic vessel
Post capillary venule
Efferent lymphatic vessel

Question 23

Which of the following generally does not apply to bone marrow (a primary lymphoid organ) but does
apply to secondary lymphoid organs?

A) cellular proliferation
B) differentiation of lymphocytes
C) cellular interaction
D) antigen-dependent response

Answer 23

D. Cellular proliferation, differentiation of lymphocytes, and cellular interactions can take place in bone
marrow. However, antigen-dependent responses occur in the secondary lymphoid organs, such as the
spleen and lymph nodes.

Question 24

Which of the following is involved in recognition of intracellular pathogens in innate immune cells?

A) Toll-like receptors (TLRs)
B) antibody
C) NOD-like receptors (NLRs)
D) complement

Answer 24

C. The NLRs are a group of cytosolic innate receptors that recognize microbes that infect cells. Once ligated, they initiate a set of cellular activities that facilitate inflammatory responses and other host defense mechanisms.

Question 25

Which of the following is a correct statement about NK cells?

A) They proliferate in response to antigen.
B) They kill target cells by phagocytosis and intracellular digestion.
C) They are a subset of polymorphonuclear cells.
D) They kill target cells in an extracellular fashion.
E) They are particularly effective against certain bacteria.

Answer 25

D. NK cells are large granular lymphocytes. Their number does not increase in response to antigen.
Their killing is extracellular, and their target cells are virus-infected cells or tumor cells(Cancerous cells). They are not particularly effective against bacterial cells

Question 26

Mature dendritic cells are capable of which of the following?
A) activating naïve antigen-specific T cells
B) removing red blood cells
C) producing bradykinin
D) extracellular killing of target cells

Answer 26

A. When immature dendritic cells are activated following their engulfment of pathogens (phagocytosis), they mature and become more efficient at antigen presentation and, in fact, can activate antigen-specific naïve T cells.

Question 27

Killer-cell inhibitory receptors (KIRs) expressed by NK cells bind to which of the following to prevent killing of normal cells:

A) complement receptors
B) MHC class I
C) immunoglobulin
D) Toll-like receptors

Answer 27

B. NK cells express KIRs, which allow them to bind to MHC class I molecules expressed on all nucleated cells that would otherwise be targets for killing when infected with certain viruses that downregulate MHC class I expression