Immunology

Question 0

Role of B cells

Answer 0

• neutralize bacterial toxins
• opsonisation of bacteria in extra cellular space
• activation of complement when bacteria in plasma

Question 1

Role of stromal nurse cells

Answer 1

Provide nutrients and growth factors to nurture and direct the differentiation of developing blood cells

Question 2

Role of CXCL12

Answer 2

Controls pre-pro B cell anchoring in correct stromal niche

Question 3

Role of IL7

Answer 3

Required for lineage progression

Question 4

Role of VCAM 1 and CAMs

Answer 4

Assist cell anchoring

Question 5

Role of cKIT/SCF (stem cell factor)

Answer 5

Interaction induces intercellular signaling pathways to drive B cell development

Question 6

Molecules expressed by mature B cells

Answer 6

• CD40
• MHC2
• BCR (IgM and IgD)
• B cell co-receptors (CD21,19,81)

Question 7

Definition of a cytokine

Answer 7

Small soluble proteins secreted by one cell that can alter the behavior or properties of the cell itself or of another cell

Question 8

Action of perforin on target cells

Answer 8

Aids in delivering contents of granules into the cytoplasm of target cell

Question 9

Action of granzymes on target cells

Answer 9

Serene proteases activate apoptosis once in cytoplasm

Question 10

Action of granulysin on target cells

Answer 10

Has antimicrobial actions and can induce apoptosis

Question 11

Definition of active immunity

Answer 11

The production if antibodies as a result of exposure to antigen

Question 12

Definition of passive immunity

Answer 12

Direct transfer of antibodies formed by another person or animal

Question 13

Pregnancy-induced factors that may immune suppress the newborn

Answer 13

• tregs
• bregs
• HLA-G+ cells
• M2 macrophages
• myeloid derived suppressor cells

Question 14

Characteristics of DiGeorge syndrome

Answer 14

• abnormal development of 3rd and 4th branchial arches

- immune dysfunction secondary to thymic hypoplasia or aplastic

Question 15

Possible B lymphocyte defects

Answer 15

• X linked agammaglobulinaemia
• CD40 ligand deficiency
• IgA deficiency
• common variable immunodeficiency (CVID)
• transient hypogammaglobulinaemia of infancy

Question 16

Differences in innate immunity in the newborn

Answer 16

• defective antigen presenting cell function

- phagocytic ability of cells is normal/increased, but less responsive to activation by cytokines

Question 17

Difference in neonatal cellular immunity

Answer 17

• gamma delta T cells more prevalent

- effective production of IFN-g

Question 18

What is different about neonate T cells

Answer 18

• produce less IFN-g

- lack constitutive perforin expression

Question 19

Which way is infant immunity skewed?

Answer 19

Th2

Question 20

Difference in neonatal humoral immunity

Answer 20

• Peyer’s patches and tonsils developed at birth but lack germinal centres for first weeks
• have delayed IgM production
• delayed ability to switch from IgM to IgG

Question 21

Which antibodies transferred transplacentally?

Answer 21

IgG

Question 22

Difference between T dependent and independent antigens

Answer 22

• dependent must contain a protein component so that T cell help can be received
• independent are multivalent