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2. Molecular components of the immune systems: Difference between revisions

(Created page with "== Antibodies == An antibody or immunoglobulin is a molecule found in the body that binds to antigens on pathogens. It does this to make it easier for the body and immune cells to get rid of the pathogens. The specific ways the immunoglobulin do this is written in more detail in topic 13. The antibodies are the main component of the humoral (non-cellular) immune response, a part of the adaptive immune response. Antibodies are basically receptors; they are proteins that...")
 
 
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=== B cell receptor ===
=== B cell receptor ===
B-cells have receptors that can bind to and recognize antigens. This B cell receptor (<abbr>BCR</abbr>) is equal to an antibody in function and structure; it’s simply an antibody connected to its cell surface. The B cell receptor does however not work alone; it needs a co-receptor called CD79. Together, this B cell receptor ''complex'' can recognize an antigen, which initiates a signal transduction cascade inside that cell.  
B-cells have receptors that can bind to and recognize antigens. This B cell receptor (<abbr>BCR</abbr>) is equal to an antibody in function and structure; it’s simply an antibody connected to its cell surface. The B cell receptor does however not work alone; it needs a co-receptor called CD79. Together, this B cell receptor ''complex'' can recognize an antigen, which initiates a signal transduction cascade inside that cell.  
Both membrane-bound (the <abbr>BCR</abbr>) and secreted immunoglobulins are identical in any given B-cell, except that the membrane-bound immunoglobulin has a transmembrane and cytoplasmic part. When the B-cell wants to produce secreted immunoglobulins instead, they splice the exons that code for the transmembrane and cytoplasmic part out of the mRNA before translation. This causes the immunoglobulin to be translated without these two parts, which causes them to be secreted instead of bound to the membrane.
[[File:T cell receptor.png|thumb|245x245px|The T cell receptor]]
[[File:T cell receptor.png|thumb|245x245px|The T cell receptor]]