Lecture 16: Immunity to Microbes

Question 1

surface lipopolysaccharides may activate the _____ complement pathway or _______ pathway

Answer 1

alternative or mannan-binding lectin complement pathway

Question 2

C3a and C5a are chemoattracts but also function in activation of

Answer 2

mast cells

Question 3

in latent viral infections, the viral DNA may be integrated into the DNA of infected cells, but ______ is produced

Answer 3

no infectious virus (ex. herpesvirus and poxvirus families)

Question 4

C-reactive protein (CRP) and serum amyloid (SAP) are prominent members of pentraxin family, which are able to bind to _____ and _____ to activate classical pathway

Answer 4

• bacterial surfaces (ligand for CRP is typically phosphorylcholine and ligand for SAP is typically phosphatidylethanolamine) and the globular heads of C1q

Question 5

What is the strongest attractant of neutrophils

Answer 5

IL-8

Question 6

Local inflammation in lymph node leads to upregulation of

Answer 6

adhesion molcules (HEVs) on lymph nodes

Question 7

relatively low affinity interaction is enhanced by the five adhesion sites on IgM, leading to higher _____ of the binding

Answer 7

avidity

Question 8

Infections caused by pathogenic extracellular bacteria have two principal mechanisms:

Answer 8

1. Tissue damage is caused by inflammation at the site of infeciton
2. bacteria produce toxins which have diverse pathologic effects
   
   • Endotoxins: which are components of bacterial cell walls
   • Exotoxins: which are secreted by the bacteria

Question 9

What are the principal mechanisms of innate immunity to extracellular bacteria

Answer 9

• complement activation
• phagocytosis
• inflammation

Question 10

• Bacterial ______ and ____ activate the alternative pathway

Answer 10

• peptidoglycan (gram-positive)
• LPS (Gram negative)

Question 11

Anaphylatoxins

Answer 11

• C4a
• C3a
• C5a