L6 - Adaptive immunity part 1 Flashcards
Give some strategic locations of antigen presenting cells
Mucosa associated lymphoid tissue (MALT) (skin, mucous membranes and tonsils)/lymphoid organs (lymph nodes, spleen)/blood circulation (DC’s)
What are considered extracellular pathogens and what are considered intracellular pathogens?
Extracellular - bacteria
Intracellular - viruses
Name two cellular components of the adaptive immune system
Antigen presenting cells/T cells/B cells/antibodies
Where in the body are the following APC’s found?
a) Dendritic cells
b) Langerhans cells
c) Macrophages
d) B cells
Dendritic cells - lymph nodes/mucous membranes/blood
Langerhans cells - skin
Macrophages - everywhere
B cells - lymphoid tisues
What cells are MHC class 1 molecules expressed on and which cells are MHC class 2 molecules expressed on?
class 1 - All nucleated cells class 2 - Dendritic cells. macrophages, B cells
Explain the two wats in which we have such a variety of MHC phenotypes
They have co-dominant expression. And because there’s several subtypes of each class we get loads of different MHC molecules.
Also they are polymorphic genes which means they recognise and present an even larger variety of antigens
Which MHC class molecules present extracellular pathogens and which present intracellular pathogens/
Extracellular - type II
Intracellular - type I
HLA (MHC) molecules are the major cause for transplant rejection in organ transplants. Certain HLA alleles are also associated with autoimmune diseases T/f?
T
The exogenous pathway (extracellular microbes) gives a humoral response whereas the intracellular pathway gives a cell-mediated response. Whats the difference?
Main thing is that humoral is antibody-mediated, involves extracellular pathogens and B cells have the major role
In cell mediated it is cel-mediated, involves intracellular pathogens and T cells have the major role
What does E. coli look like down a microscope?
Gram negative rod
Most E. coli strains are lactose fermenting and can be distunghised as such by growing the organism in MacConkey agar. What colour would the organism go if it was actose fermenting?
Pink, non-lactose colonies would be yellow
Diarrhoeagenic E.coli infections should not be treated with antibiotics, neonatal meningitis shoud be treated with ceftoxamine. What should the rest of E. coli infections be treated with?
Trimethoprim first line second line nitrafurantoin
