Lecture 8 Flashcards
What are some examples of gram positive bacteria?
Staphylococcus aureus
What are some examples of gram negative bacteria?
Campylobacter, salmonella, shigella
What is the difference between the structure of gram negative and gram positive bacteria?
Peptidoglycan layer on gram positives
What does recognition of LPS and peptidoglycan do?
Bind to toll like receptors
how many toll like receptors are there in humans?
10
Where can toll like receptors be found (TLR)?
On the surface or internally
What is an example of a TLR that can be found on the surface?
TLR4
What is an example of TLR that are found intracellualrly?
NOD
What do TLR recognise on the pathogen?
PAMPs
What do TLR help with?
Help with inflammation, recruits cells and helps with differentiation of B cells and dendritic maturation
How can some bacteria escape phagocytosis?
By protective capsules and opsonisation
What can a conjugate vaccine help with?
Developing an appropriate immune response
Why are antibodies important against bacteria?
For opsonisation
What does opsonisation bind?
FC receptors on phagocytes
How does the complement system promote inflammation?
C3a and C5a
What Does C3b (opsonin) do in the complement system?
Helps with phagocytosis adding another layer of sugar coating to the pathogen
What does the membrane attack complex do in the complement system?
Makes a pore in the pathogen and water goes in and bursts the pathogen
What is the membrane attack complex important against?
Gram negative bacteria
What is the tetanus toxin?
Causes locked jaw and muscle
How does bacteria help with the tetanus toxin?
It neutralises the toxins and stops adherence of the mucosal surface
What can gram negative bacteria be killed by?
Complement lysis
When are bacteria cells most susceptible to the effects of the membrane attack complex?
When they are dividing
What bacteria can survive within phagocytes?
Mycobacterium tuberculosis
What response is important in situations where the. Bacteria has survived in the phagocytes?
TH1 response
What are activated macrophages good at?
Stimulating inflammation
What can be found on the surface of macrophages?
MHC 1 and 2
What are macrophages central to?
TH1 response
What are the two distinct form of leprosy?
Tuberculosis and lepromatous
What is tuberculosis leprosy driven by?
TH1 response
What type of cells are released in tuberculoid leprosy?
CD4+ cells generate macrophages and cytotoxic cells to be stimulated
What is lepromatous leprosy driven by?
TH2 response
What does lepromatous leprosy lead to?
Sometimes death
What symptoms is involved in leprotamous leprosy?
Extensive skin involvement
What are granulomas?
A cluster of white blood cells and other tissues
What are T cell effector mechanisms important for protection against?
Intracellular organisms
