Antibodies Flashcards
Antibody structure:
2x — chains and 2x — chains
How are these chains held together?
What is the FAB fragment? what does it allow for?
What is the Fc fragment? what does it bind to and why?
Associated molecules allow — signalling.
Secreted antibodies have same — as membrane bound — receptor.
Light, Heavy
Disulfide bridges
region of antibody that binds to antigen, allows for Ag binding specificity
fragment crystallisable region, binds to cells to create and effector function.
intracellular
specificity
B-cell
Antigen specific recognition:
specificity depends on the — of the — region
It recognises — shapes on the —, it binds to a region on these called the —. Each antigen may have more than one of these.
shape variable 3D antigen epitope
Antibody specificity; HEAVY CHAINS These are coded by... on chromosome number... LIGHT CHAINS Multiple gene segments for both chains on chromosome number - and - HEAVY and Light any combination possible innacurate joining of VDJ increases --- errors during ---/--- increases ---
B cell genes 14 2 and 22 variability cell division variability
Antibody class switching is a — mechanism that changes a —/— production of — from one to the other. During this process, the — region of the — chain is changed but the — region of the — chain is retained. Since the — region stays the same, class switching does not affect antibody —. Instead, the antibody retains the same — for the same — but can interact with different — molecules.
More specifically, it happens in the B-cell — in the —/—
Needs help from —/— and — recognition
It is also called —/—
biological B-cells antibody constant heavy variable heavy variable specificity affinity antigens effector follicles lymph nodes T cells antigen Affinity maturation
Antibody — functions are mediated by the — end of the antibody. The Fc is specific for each — of antibody.
7 effector functions:
effector Fc class complement classical pathway opsonization recognition phagocytosis Killing sensitization cell activation
IgM and acute/primary responses:
primary response, high avidity.
The – binds to phagocytes which strongly activates the —,— pathway
Fc
classical
complement
IgG and secondary response: --% of total serum Ig half-life of -- days heavy chains are - chains Is part of the --- response It transfers across the --- activates the ---/--- pathway strongly binds to phagocytes, phagocytosis induced by ---
75 21 y secondary placenta classical complement opsonins
IgA, IgA1 and secretory IgA2: -- to --% of serum Ig --- heavy chains 80% monomer --- in human serum 20% dimer --- secreted from --- cells into ---, ---/--- and --- Neutralising --- at ---/---
15-20 alpha IgA1 IgA2 epithelial mucous breast milk saliva antibody mucosal surfaces
Transport of IgA across mucosal epithelia:
It binds to —/—/— on the — surface of epithelial cells.
Its taken into the cell by —
It travels through the cell and is secreted on the —/— of the epithelial cells while still attached to the —.
— of the receptor occurs and the IgA is free to diffuse through the lumen
polymeric immunoglobulin receptor mucosal endocytosis luminal surface receptor proteolysis
IgD- The B cell receptor:
Makes up less than –% of serum Ig
The heavy chains are — chains
It has — pieces to anchor it across the — cell membrane
It forms an — specific receptor on — — cells
It is the only antibody with no known — function
1 Delta tail anchor B antigen mature B effector
IgE acts as a --- cell receptor Very little igE in the --- --- and ---/--- cells express v.high affinity for IgE The fc region causes what effect? sensitises --- cells and tissues protects against --- parasites. associated with ---
mast serum Basophils, tissue mast release ofhistamine mucosal Helminth allergy
Antibody types:
Isotypes, these are the - different classes of antibody.
Allotypes are — specific antibodies
Idiotypes describe the set of — on the — region
5
person
epitopes
variable
Antibodies have Fab and Fc regions which control —/— and — respectively. Antbodies bind to – regions called —/—, they can be specific or —/—. Antibody specificity is controlled by the — region, which is the —. Antibody function is controlled by the — of antibody, which is the —, the – region and thus the — chain.
antigen binding function, 3D, antigenic epitopes cross reactive V, idiotype class, isotype Fc, heavy
