Chapter 7

Question 1

Cathelicidins

Answer 1

• Epithelial antimicrobial
• A type of antimicrobial peptide that is secreted by epithelial cells to destroy potential pathogens
• have a alpha-helical shape and only one is known to function in humans
• Stored in neutrophils, mast cells, and epithelial cells

Question 2

Defensin

Answer 2

• Epithelial antimicrobial
• A type of antimicrobial peptide that is secreted by epithelial cells to destroy potential pathogens; there are two types alpha-defensins (must be activated by proteolytic enzymes) and B-defensins (are synthesized in active forms)

Question 3

Collectins

Answer 3

• Epithelial antimicrobial
• A family of glycoproteins that are secreted by the lung
• React with different affinities to carbohydrates and lipids on the surfaces of a wide array of pathogenic microorganisms

Question 4

Mannose-binding lectin (MLB)

Answer 4

• Epithelial antimicrobial
• Recognizes a sugar commonly found on the surface of microbes and is a powerful activator of a plasma protein system (complement), resulting in damage to bacteria or increased recognition by macrophages

Question 5

Resistin-like molecule B

Answer 5

• Epithelial antimicrobial
• Is found in the intestinal goblet cells, where it appears to protect against helminth infections

Question 6

Bactericidal/permeability-inducting (BPI) protein

Answer 6

• Epithelial antimicrobial
• Is stored in neutrophils and intestinal epithelium
• Specifically reacts with lipopolysaccharide on the surface of gram-negative bacteria, resulting in bacterial lysis

Question 7

Antimicrobial lectins

Answer 7

• Epithelial antimicrobials
• Are carbohydrates that are found in the intestinal epithelium and have activity against gram-positive bacteria

Question 8

Plasma protein systems

Answer 8

There are 3 key plasma protein systems that are essential to an effective inflammatory system
- Complement system
- Clotting system
- Kinin system

Question 9

Proenzymes

Answer 9

• Part of the plasma protein system
• proteins/enzymes that circulate in inactive forms
  -Once one is activated, it activates more, resulting in a cascade

Question 10

Complement System: Classical pathway

Answer 10

Activated by proteins of the adaptive immune system (antibodies) bound to their specific targets (antigens)

Question 11

Complement System: Lectin pathway

Answer 11

Activated by mannose-containing bacterial carbohydrates

Question 12

Complement System: Alternative pathway

Answer 12

Activated by gram-negative bacterial and fungal cell wall polysaccharides

Question 13

Complement Cascade

Answer 13

Different pathways of the complement system all converge at the third component (C3)

Question 14

Antigen-antibody complex

Answer 14

This complex activates the classical pathway of the complement system

Question 15

Opsonin

Answer 15

Are molecules that “tag” microorganisms for destruction by cells of the inflammatory system (primarily neutrophils and macrophages)

Question 16

Kinin System

Answer 16

The third system in the plasma protein system. The primary product of this system is bradykinin

Question 17

Bradykinin

Answer 17

-Produced by the kinin system
- Causes the dilation of blood vessels, acts with prostaglandins to stimulate nerve endings and induce pain, causes smooth muscle cell contraction, increases vascular permeability, and may increase leukocyte chemotaxis

Question 18

PRRs

Answer 18

• Pattern recognition receptors
• Recognize molecular “patterns” on infectious agents or their products
• A type of cellular receptor

Question 19

PAMPs

Answer 19

• Pathogen-associated molecular patterns
• A type of cellular receptor

Question 20

DAMPs

Answer 20

Damage-associated molecular patterns
- Recognize products of cellular damage
- A type of cellular receptor

Question 21

Integrins

Answer 21

Are cell surface receptors that have a role in cell adhesion and attachment and mediate intracellular signaling within the extracellular matrix

Question 22

Scavenger receptors

Answer 22

Cellular receptors that are primarily expressed on macrophages and facilitate recognition and phagocytosis of bacterial pathogens, as well as damaged cells and altered soluble lipoproteins associated with vascular damage
- Some can help identify and remove old red blood cells and cells undergoing apoptosis

Question 23

NLRs

Answer 23

Are cytoplasmic receptors that recognize products of microbes and damaged cells

Question 24

Cytokines

Answer 24

Constitute a large family of small-molecular-weight soluble intercellular-signaling molecules that are secreted, bind to specific cell membrane receptors, and regulate innate or adaptive immunity
- Can be either proinflammatory or antiinflammatory
- Binding of cytokines to a target cell often induces the synthesis of additional cellular products

Question 25

Chemokines

Answer 25

Are members of a special family of cytokines that are chemotactic and primarily attract leukocytes to sites of inflammation

Question 26

Interleukins

Answer 26

Are biochemical messengers produced predominantly by macrophages and lymphocytes in response to stimulation of PRRs or by other cytokines

Question 27

TNF-a

Answer 27

Tumor Necrosis Factor-alpha
- It is secreted by macrophages and other cells in response to the recognition of PAMPs by TLRs (toll-like receptors)

Question 28

Leukotrienes

Answer 28

Are products of arachidonic acid, which is released from mast cell membranes by an intracellular phospholipase that acts on membrane phospholipids
- produce effects similar to those of histamine: smooth muscle contraction, increased vascular permeability, and neutrophil and eosinophil chemotaxis
- Appear to be important in the later stages of the inflammatory response because they stimulate slower and more prolonged responses than do histamines

Question 29

PAF

Answer 29

Platelet Activating Factor
- Is produced by the removal of a fatty acid from the plasma membrane
- produced by mast cells
- can be produced by neutrophils, monocytes, platelets, and endothelial cells during the inflammatory process
- Work similar to leukotrienes: causing endothelial cell retraction to increase vascular permeability, leukocyte adhesion to endothelial cells, and platelet activation

Question 30

PMN

Answer 30

Polymorphonuclear Neutrophils
- Are the predominant phagocytes in the early inflammatory site, where they ingest bacteria, dead cells, and cellular debris

Question 31

CAMs

Answer 31

Cell Adhesion Molecules
- Are a family of transmembrane proteins that provide adhesion between cells or between a cell and components of extracellular matrix (fibronectin, collagen, fibrinogen)

Question 32

Selectins

Answer 32

Are CAMs that bind carbohydrate ligands on transmembrane glycoproteins
- E selectins are found on endothelial cells
- L selectins on leukocytes
- P selectins on platelets and endothelial cells