Week 3 Diebel Bacterial Pathogenesis and Host Defense Flashcards Preview

Foundations > Week 3 Diebel Bacterial Pathogenesis and Host Defense > Flashcards

Flashcards in Week 3 Diebel Bacterial Pathogenesis and Host Defense Deck (16)
Loading flashcards...
1
Q

What type of toxin forms a hole in the host’s cell membrane?

A

Cytolytic exotoxin

2
Q

What are three types of hemolysins? Describe each type.

A

gama-non hemolytic
alpha-damage RBC but don’t destroy
beta-very hemolytic, destroy cell

3
Q

How do AB toxins work?

A

“B” toxin, binds to receptor protein

“A” toxin, released into cytoplasm causing some form of metabolic disruption

4
Q

These toxins affect excitation signals from the CNS.

A

Neurotoxins

-can inhibit contraction (botulism)
or
-can inhibit relaxation (tetnus)

5
Q

These exotoxins link to t-cells causing “runaway” massive systemic inflammatory response

A

superantigens

6
Q

Whats a PAMP?

A

Pathogen Associated Molecular Pattern

-recognized by PRRs (innate)

7
Q

What are complement components of the innate immune system?

A

serum proteins that bind to invading organisms and facilitate their phagocytosis

their overall goal is to control inflammatory response

activation is a cascade rxn

can be activated by antibodies or mannose binding lectin to the pathogen surface

8
Q

What are interferons?

A

cytokines that mediate early response to viral infections by the innate immune system

Type 1: IFNa and IFNb are produced by infected cells

Type 2: IFNgama are released by T cells

9
Q

What are PRRs?

A

Pattern Recognition Receptors-recognize PAMPs and trigger macrophage response to invasion

10
Q

What are toll-like receptors?

A

a family of PRRs that bind PAMPs

TLR1-TLR9

11
Q

What are APCs?

A

Antigen Presenting Cells

they link innate and adaptive immune systems by taking up and processing antigens so they can be recognized by t-cells

12
Q

Definen epitope.

A

restricted part of antigen bound by antibodies

13
Q

antibodies are?

A

immunoglubulin molecules that bind antigens with a high degree of specificity “tagging” them for destruction

14
Q

What is the purpose of the constant or Fc region of an antibody?

A

binds to Fc receptors on phagocytes initiating phagocytosis of the bound antigen

15
Q

What are the differences between active and passive immunity?

A

Active: the outcome of exposure to an antigen

  • immune response made by infected individual
  • immune memory in effect
  • response can be maintained
  • develops over a period of weeks

Passive: acquisition of PREFORMED immune cells or antibodies from a donor

  • no exposure to antigen
  • no immune memory
  • not maintained
  • immunity develops immediately
16
Q

What is an enterotoxin?

A

exotoxin that targets the intestines