Lec1-3 Overview and Innate Immunity

Question 1

What is mech of multiple slcerosis

Answer 1

• immune attack against myelin basic sheet that insulates neurons

Question 2

Is innate or adaptive immune more specific

Answer 2

adaptive

Question 3

Is there more diversity in receptors of innate or adaptive?

Answer 3

Adaptive - due to somatic recombination of gene segments

Question 4

What are 5 main components of innate immunity?

Answer 4

• barriers to infection [epithelium/skin]
• phagocytes
• dendritic cells
• NK cells
• complement

Question 5

What make cell type make up pus?

Answer 5

neutrophils

Question 6

What is principle function of B lymphocytes in immune

Answer 6

• mediate humoral immunity

Question 7

What is the principle function of T lymphocytes in immune

Answer 7

Mediate cell-mediated immunity

Question 8

Are natural killer cells in innate or adaptive immune?

Answer 8

innate

Question 9

What is the principle fcuntion of dendritic cells in immune?

Answer 9

= act as antigen presenting cells, initiated T cell response

Question 10

What is the principle function of follicular dendritic cells?

Answer 10

• display antigens to B cells in humoral immune response

Question 11

What types of barriers involved in innate immune

Answer 11

1. physical barrier to infection [skin]
2. killing of microbes by locally produced antibiotics
3. killing of microbes by intrapepithelial lymphocytes

also: resident flora, chemical barriers

Question 12

Are neutrophils or macrophages short lived?

Answer 12

neutrophils!

Question 13

What are PAMPS?

Answer 13

• pathogen associated molecular patterns
• recognized by toll like receptors (a type of pattern recognition receptor [PRR] ) on surface of DC/macrophage and trigger activation

Question 14

Endpoint of TLR signalling cascade

Answer 14

Part of innate immune

1. increase expression cytokines/adhesion molec –> acute inflamation, stimulate adaptive immune
2. increase production IFN –> antiviral state

Question 15

What are NLRs? Endpoint?

Answer 15

NLR = nod-like receptor

- release IL-B: fuel acute inflammation and fever

Question 16

5 Characteristics of inflammation

Answer 16

• heat
• redness
• swelling
• pain
• loss of function

Question 17

Macrophages as sentinels

Answer 17

• recognize pathogens or cell death product

Question 18

2 Natural Killer Cell Functions

Answer 18

1. Nk cell sees infected cell ad kills it
2. NK cell binds macrophage that has phagocytosed molecule, releases IFN-gamma that activates macrophage to kill phagocytosed microbe

Question 19

How are NK cells inhibited?

Answer 19

• inhibitory receptor on NK cell binds self class I MHC-self peptide complex on normal cell so not activated and does not kill
• when NK binds virus infected cell that has little class I MHC expressed, no inhibitory receptor so kills cell

Question 20

3 Paths of complement activation

Answer 20

1. Alternative: microbe initiates activation
2. Classical: microbe bound to antibody initiates
3. Lectin: microbe bound to mannose-binding lectin initiates

Question 21

Which pat of complement peptides gets deposited on the microbe?

Answer 21

C3b

Question 22

What happens to C3 in complement?

Answer 22

• C3a breaks off and stimulates inflammation

- C3b is deposited on microbe and aids in phagocytosis

Question 23

Type 1 Interferon [IFN] pathway? 3 Mechanisms of viral inhibition

Answer 23

• IFN produced by virus infected cell
• binds IFN receptor on uninfected cell
• Mechanisms of blocking viral replication
  1. degrades viral DNA
  2. inhibits viral gene expression
  3. inhibits viral protein synthesis