Bacterial Escape Flashcards
1
Q
Bacterial host evasion strategies from epi defense mechanisms
A
- prevention of opsonization
- toxin secretion
- prevention of microbial recognition
- blockage of antimicrobial peptides
- inhibition of chemokines
- bacterial-induced uptake
- interfere with signaling
- phagosomal escape
- persistence in endosomes
2
Q
Bacterial defense against phagocytes
A
- induction of programmed cell death
- inhibition of uptake
- down-regulate nuclear host responses
- phagosomal escape
- prevent phagosomal maturation
- inhibit host microbicidal mechanisms
3
Q
Bacterial defense against adaptive immunity
A
- induction of immuno-suppresssive cytokines
- inhibition of comstim molecules
- prevention of bacterial uptake
- prevention of phagosomal maturation
- prevention of Ag processing
- inhibition of MHC
- inhibition of tyrosine phosphorylation on TCR
- activation of inhibitory rec
- induction of Tregs
- induce T cell apoptosis
4
Q
LLO
A
Lysteriolysin O
5
Q
How does L. monocytogenes evade host?
A
- adhesion and invasion (IniA and IhiB)
- escape from vacuole (LLO)
- actin polymerization and propulsion through cytosol (ActA)
- escape form secondary vacuole (Mpl, LLO)
6
Q
What is needed for optimal mac-mediated phagosomal containment of L. monocytogenes
A
Protein Kinase C d
7
Q
How to quantitate percentage free and trapped Listeria bacilli
A
- stain Listeria green and actin of mac red
- white = phagosome
- greed = trapped
- yellow = free
8
Q
How does Simvastatin protect against L. mono infection?
A
- counteracts Listeria-induced phagosomal escape
9
Q
Main host evasion tactic used by Mtb
A
prevents phagosomal maturation
10
Q
Define autophagy
A
- an intracell degradation system that delivers cytoplasmic constituents to the lysosome
11
Q
Describe deep cage technology
A
- promotor level analysis
- use of next-gen sequencers
- unique bioinformatics analysis
12
Q
Functions of LncRNA
A
- Recruitment of chromatin modifiers
- controlled recruitment of TFs
- regulation of splicing
- regulation go chromosome looping
- formation and function of subnuclear structures
- control of translation rate
- control of mRNAdecay
- miRNA sequestration
13
Q
How does Mtb suppression of miRNA let-7f expression work?
A
- augments target ecpression (A20 = inhibitor of NF-kB)
- A20 limits inflam response and NO production
- promotes survival of Mtb in macs
14
Q
Host factors hijacked by Mtb
A
- evasion of phagosome maturation
- evasion of killer effector functions
- evasion of Ag presentation
