Antibody mediated immunity Flashcards
what can antibodies only attach too ?
their specific antigen
when are the antibodies produced?
by the B lymphocyte that proliferates and then differentiates into a plasma cell.
what are the antigens presented on ?
the MHC class II surface proteins.
does the pathogen have recognition by one antibody or multiple and why ?
multiple as they have different antigens for the pathogen i.e external . internal
why is the size of the pathogen important ?
as this determines what response will be used
what is a thymus depend antibody ?
this is when the antigen requires help from the T cell in cooperation with the B cell to synthesize the antibody.
what is a thymus independent antigen ?
this is when the antibody can be syntheisses form the B cell without any help from the T cell. They are often less complex than the thymus dependent antigens.
if there is a high response of antibodies then what will the end point titre look like ?
it will be a high end point titre
if there is a low response of antibodies then what is the end point titre look like ?
it will be a low point end titre
how does antibodies lead to killing by activating the NK cells ?
The antibody binds to the antigen on the surface of a target cell. The Fc receptors on the NK cells recognise the bound antibody. Cross linking occurs of the fc receptors and this signals the NK cell to kill the target cell by apoptosis.
the antibodies can mediate damage or killing by the granulocytes , how ?
The resting mast cell has granules that contain histamine and other inflammatory mediators. When the antibody activates the mast cell this results in the IgE antibody cross linking with the antigen and this releases the granules contents.
how come the cytokines present have an impact on the type of antibody response produced ?
the cytokines need to activate the B cell and they activate the production or inhibition of the specific antibodies.
what must the BCR be complimentary to ?
the cytokine
are the antibodies present in the body at all the same levels ?
nope they are present at different levels throughout the body
What is IgG important in ?
protecting the gut , it is transported into the gut lumen through the epithelial cells at the base of the crypts. Also complement.
