recognition of pathogens

Question 1

what is the name of the receptor present on immune cells which is responsible for pathogen recognition?

Answer 1

pattern recognition receptors

Question 2

what do pattern recognition receptors recognise?

Answer 2

pathogen associated molecular patterns

Question 3

what are the major PRR families?

Answer 3

toll like receptors
C-type lectin receptors
nod like receptors

Question 4

what is the BASIC pathway of pathogen recognition?

Answer 4

pathogen associated molecular pattern recognised by pattern recognition receptor
activation of downstream signalling pathways
activation of transcription factors
cellular response

Question 5

where are PRR’s located?

Answer 5

both on outer plasma membranes and inner membranes such as on endosomes

Question 6

how are bacterial pathogens recognised?

Answer 6

bacterial PAMPS (peptidoglycan) is recognised by host TLR 4 receptors 
activated TLR 4 binds to MyD88 (a adapter molecule)  which activates NK-kappa B which initiates gene transcription of IFN-gamma

Question 7

how are fungal pathogens recognised?

Answer 7

fungal PAMP’s (beta glucan) is recognised by host dectin-1 receptors
activated dectin-1 receptors bind to CARD-9 (an adaptor molecule) which activates NK-kappa B
NF-kappa B then initiates the transcription of IL-17 gene

Question 8

how are viral pathogens recognised?

Answer 8

viral dsDNA are recognised by RIG1 receptors
the activated receptors activate MAVS
MAVS activate transcription factor IRF-3 and NF-kapa B which initiate the gene transcription of type 1 interferons