Lecture 3

Question 1

PAMPs

Answer 1

-pathogen associated molecular patterns found on pathogens and necessary for their survival

Question 2

DAMPs

Answer 2

-damage associated molecular patterns such as dead tissue

Question 3

Specific TLRs bind to different PAMPS:

• TLR-2
• TLR-4
• TLR-3,7,8
• TLR-9

Answer 3

• TLR-2: gram positive bacteria
• TLR-4: gram negative bacteria
• TLR-3,7,8: RNA within endosome (ssRNA)
• TLR-9: DNA containing unmethylated CpG DNA in endosome

Question 4

How do inflammasomes become activated after PRR bound to bacterial or viral molecule?

Answer 4

-activated by DAMPs or PAMPs to produce cytokines

Question 5

What cytokine do NK cells release which aids in macrophage phagocytosis of microbes?

Answer 5

-interferon gamma

Question 6

How do NK cells prevent destruction of normal cells?

Answer 6

-NK cells have an inhibitory receptor which binds to MHC class I on normal cells

Question 7

What is the role of the complement protein C3b?

Answer 7

-C3b causes opsonization and leads to phagocytosis

Question 8

How are neutrophils recruited to sites of inflammation?

Answer 8

• rolling
• integrin activation by chemokines
• stable adhesion
• migration through endothelium

Question 9

Where are E-selectin, P-selectin, and L-selectin found?

Answer 9

• E and P selectin- endothelial cells

- L selectin- recirculating B&T cells

Question 10

How can pathogens evade defenses of innate immune system?

Answer 10

• reduce phagocytosis- capsular polysaccharide
• reduce ROS- increase catalase to break down ROS
• complement resistance- sialic acid inhibits covertase and M protein blocks C3 binding
• resistance to antimicrobial peptides-synthesis of modified LPS resistant to peptide antibiotics

Question 11

What is the biological effect of TNF?

Answer 11

• activate ECs and neutrophils

- cause fever and weight loss

Question 12

What is the biological effect of IL-1?

Answer 12

-similar to TNF and activate ECs and neutrophils

Question 13

What is the biological effect of IL-6?

Answer 13

• fever

- liver acute phase proteins

Question 14

What is the biological effect of Il-8?

Answer 14

• leukocytes-activation
• chemotaxis
• increase integrin affinity

Question 15

What is the biological effect of IL-12?

Answer 15

• NK cells increase INF-gamma

- cytoxicity

Question 16

What is the biological effect of IFN-gamma?

Answer 16

• macrophage activation

- increase antibody response

Question 17

What is the biological effect of Type I IFN?

Answer 17

• increase anti-viral state

- activate NK cells

Question 18

What is the biological effect of IL-10?

Answer 18

-suppress immune system