Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Immunology > Lecture 16- Immune Response to Bacteria/Fungi > Flashcards

Lecture 16- Immune Response to Bacteria/Fungi Flashcards

1
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Pathogen

A

Bacterium or virus or other microorganism that can cause disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Opportunistic pathogen

A

Bacterium, virus or other microorganism that can cause disease in people with impaired immunity but not in healthy individuals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Being a pathogen means to evade ____

A

Innate immunity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is an example of a non-pathogen that is resident of mammalian microbiotia

A

E. Coli K12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What can enteropathogenic and enterotoxigenic eschirichia coli cause

A

Diarrheal diseases in dogs and cats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What body surface has the most bacterial cells

A

Colon- 10^12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

inflammatory bowl disease is a ____ response to microbiota

A

Adaptive immune response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does the immune system respond to non-pathogens

A

Complement, phagocytosis, adaptive response to microbiota

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How do pathogens evade the immune system

A

Antigenic variation, antigenic drift, molecular mimicry, and virulence factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is antigenic variation

A

Change in H/N molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is an example of antigenic drift with Salmonella

A

Change in arrangement of promoters leads to differential expression of flagellin protein in salmonella

Facing one way we have repressor citrates so no salmonella, but undergo DNA inversion can turn off repressor and activate salmonella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does Pili evade immune system

A

Highly antigenic carries 10-20 silent promoters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is antigenic drift

A

Natural mutations over time lead to changes in structure of proteins that may be targeted by antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is molecular mimicry

A

Sequence similarities between self and virus

Can result in lack of antibody response to antigen and cross-responsiveness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How is Lyme a example of virulence factor

A

Resists complement mediated phagocytosis by producing osp proteins that binds Factor H. Acts like C3b binding factor H which causes inactivation of complement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How does a capsule evade the immune system

A

Inhibits phagocytosis

Important for extracellular bacteria

18
Q

IgA proteases

A

Cleave IgA at hinge making ineffective can’t act at mucosal surfaces

19
Q

Why is sialyation of LPS bad

A

Salic acid is on host cells not bacteria so LPS is on gram - bacteria can add Salic acid and fake being host cell

20
Q

What does listeria monocytogenes cause

A

Gastroenteritis

21
Q

What does listeria monocytogenes produce

A

Listeria lysin O or LLO that degrades phagosome and therefore replicates in cytoplasm and hijacks host cell and uses act A to propel itself

22
Q

What is the innate immune response to intracellular bacteria

A

Phagocytosis and NK cell activity

23
Q

Macrophages response to intracellular bacteria

A

Macrophages secrete IL-12 and IL-15 to recruit NK cells, NK cells will proliferate and secrete INF-y and will bind to macrophages to tell them to increase phagocytosis and release inflammatory cytokines

24
Q

When will NK cell target foreign invader

A

Downregulation of MHC I

25
Q

What is the adaptive response to intracellular bacteria

A

Cell mediated immunity, IL-12 stimulates TH1 response resulting in INF-y and expression of CD40L to activate macrophages

26
Q

How do CD8+ T Cells respond to intracellular bacteria

A

Kill bacteria displaying on MHC I molecules via Perforin and granzymes

27
Q

How do antibodies respond to intracellular bacteria

A

They play a minor role but can use ADCC- antibody’s bind target cell, FC receptors on NK cell recognize bound antibodies, crosslinking activates NK cell to release toxic granules and kill cell

28
Q

How do intracellular bacteria evade immune system

A

Escape the phagosome, prevent phagosome-lysosome fusion and resistant to lysosomal enzymes

29
Q

What are the mechanisms of pathogenesis of extracellular bacteria

A

Release toxins endotoxins and exotoxins

30
Q

What are endotoxins and example

A

LPS- activator of macrophages causes release of cytokines and activates alternative complement

31
Q

What are exotoxins and exmaple

A

Either stimulate cytokine release or are cytotoxic to other cells

PMT in atrophic rhinitis in swine disrupts cell signaling leads to bone resorption and disrupted bone formation by messing with GPCR’s and disrupting GTP—> GDP and cell will die of apoptosis

32
Q

What is the innate response to extracellular bacteria

A

Physical barriers, antimicrobial peptides- lysozymes and defensive

33
Q

What is the adaptive response to extracellular bacteria

A

Antibodies

34
Q

How do fungal pathogens evade immune system

A

Persistence within phagocytes, inflammation, CTL activity

35
Q

What type of PRRs do macrophages and dendritic cells express to recognize fungal cell wall components

A

TLR’s and Dectins

36
Q

What is the adaptive immune response to fungal pathogens

A

Cell mediated stimulated by cytokines from dendritic cells

37
Q

Dendritic cell recognizes a fungal pathogen and results in activation of innate effector cells and _____

A

Generation of TH1/Th17 adaptive responses

38
Q

What is the adaptive immune response to intracellular fungi

A

TH1 and CTL’s

39
Q

What is the response of the adaptive immune system to extracellular fungi

A

Th17- stimulate neutrophils

40
Q

What are some fungal pathogen evasion tactics

A

Biofilm to resist phagocytosis, mask antigens, capsules, obtain nutrients like iron and zinc, inactive antimicrobial peptides

Immunology (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions