Lecture 1

Question 1

How do intra and extracellular pathogens establish infection?

Answer 1

The pathogen attachment and entry into host, extracellular pathogens will then replicate and spread to cause either local and systemic infections
Intracellular pathogens will enter into cells and replicate and then go on to spread infection

Question 2

What are the barriers to infections from pathogens?

Answer 2

Lysozyme in tears, mucus and cilia in the bronchi, acids and rapid pH change in the gut, commensals in the gut, skin fatty acids and commensals

Question 3

What is the difference between PAMPs and antigens?

Answer 3

PAMPS are general structures recognized by the innate immune system
Antigens are the highly specific structures recognized by the adaptive immune system

Question 4

What are the 3 phases of host immune defense?

Answer 4

Pre-existing innate immunity such as skin, mucosal barriers, pH, saliva and proteases
After 4 hours induced innate immune factors such as complement activation, phagocytosis, target cell lysis and inflammation
After 96 hours the adaptive immune system factors such as B and T lymphocytes have an effect