- published: 24 Dec 2013
- views: 84405
An antibody, also known as an immunoglobulin, is a large Y-shaped protein produced by B-cells that is used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. The antibody recognizes a unique part of the foreign target, called an antigen. Each tip of the "Y" of an antibody contains a paratope (a structure analogous to a lock) that is specific for one particular epitope (similarly analogous to a key) on an antigen, allowing these two structures to bind together with precision. Using this binding mechanism, an antibody can tag a microbe or an infected cell for attack by other parts of the immune system, or can neutralize its target directly (for example, by blocking a part of a microbe that is essential for its invasion and survival). The production of antibodies is the main function of the humoral immune system.
Antibodies are produced by a type of white blood cell called a plasma cell. Antibodies can occur in two physical forms, a soluble form that is secreted from the cell, and a membrane-bound form that is attached to the surface of a B cell and is referred to as the B cell receptor (BCR). The BCR is only found on the surface of B cells and facilitates the activation of these cells and their subsequent differentiation into either antibody factories called plasma cells, or memory B cells that will survive in the body and remember that same antigen so the B cells can respond faster upon future exposure. In most cases, interaction of the B cell with a T helper cell is necessary to produce full activation of the B cell and, therefore, antibody generation following antigen binding. Soluble antibodies are released into the blood and tissue fluids, as well as many secretions to continue to survey for invading microorganisms.
The past
You realize you're dead
Smiles upon your grave
A victim and a slave
Crawling beside yourself
Walking, no shadow
Did you hurt to heal?
Guess what; THIS PAIN IS REAL
YOU SUFFER
THIS PAIN IS REAL
Created people
Forced to feel the mark of death
To many living witness
Who lost their right to live
No flesh, no glory
Your greasy smile has disappeared
Did you die to feel
You'll see; THIS PAIN IS REAL
YOU SUFFER
THIS PAIN IS REAL
Did you hurt to heal
Did you die to feel
To see how's live in damnation
THIS PAIN IS REAL
Did you hurt to heal
Did you die to feel
To see how's live in damnation
Did you hurt to heal
Did you die to feel
A chapter closed and sealed