W3-3 Bacteria pathogenesis Flashcards Preview

Foundations > W3-3 Bacteria pathogenesis > Flashcards

Flashcards in W3-3 Bacteria pathogenesis Deck (27):
1

What is the LD50 of a pathogen?

the amount required to kill 50% of organisms (measures virulence)

2

Extoxin

secreted from bacteria to affect host somewhere else

3

Endotoxin

intrinsically part of host, but removed and secreted to host for toxic effects

4

Hemolysis test: tests for what type of toxicity?

extoxins: cytolytic

5

Three possible results of hemolysis test

α: partial hemolysis, leaves green edge

β: total hemolysis, large missing area

γ: culture grows but no hemolysis

6

Describe AB toxins: type and action

Type: exotoxins

Action: B unit Binds to host cell and A unit carries out toxic Action

7

Flacid paralysis cause and example

Inhibits ACh at NMJ

botulism

8

Spacstic paralysis cause and example

inhibits glycine release on inhibitory neuron, does not allow relaxation

tetanus

9

What is a super antigen?

One that stimulates the specific immune system more than it should in a nonspecific manner. Leads to large amounts of inflammation

10

What are the three parts of an endotoxin?

1. Lipid

2. Core polysaccharide

3. O-specific polysaccharide

11

What is the toxic part of an endotoxin?

lipid

12

What is the function of the O-specific polysaccharide of an endotoxin clinically?

unique to organism, identifiable in lab setting

13

Which is more toxic: endotoxin or exotoxin?

exotoxin

14

3 types of hypersensitivity immune responses

T1: allergy

T2: antibodies against pathogen also attack host

T3: WBCs pull pathogens out of tissue to attack in dangerous areas like capillaries

15

The innate immune system counts on these molecules to be present on pathogens

PAMPs--pathogen associated molecular patterns

16

These protein components of serum may bind to pathogens and help facilitate their phagocytosis

complement components

17

Interferons

mediate early cellular response to viral infections

18

Differentiation of immune system cells

a

19

These cells respond immediately to infection

macrophages

20

These cells are recruited by mircophages at the beginning of infection

neutrophils

21

What is the purpose of the complement system?

to control inflammation

22

Interferons

Produced by infected cells to recruit immune cell response

23

Which cells are responsible for initiating the adaptive immune response?

phagocytes from innate response

24

Cells responsible for bringing antigens to T-cells

Antigent Presenting Cells

25

Immune system produces these in response to antigens perceived as dangerous

antibodies

26

Two types of immunity

Active: host body initiates an immune response

Passive: antibodies are transferred from another person (either transfusion or from mother)

27