Amino acids are a group of compounds with the general molecular structure of:
mAb-nificent!
Monoclonal antibodies (mAb) are proteins that are produced in a laboratory or plant and can act as antibodies which are produced by the human body. They are “monoclonal” because they are clones, or exact copies of an antibody. The “mono” refers to being the clone of a single antibody which binds to a single antigen. At AbbVie we design, develop, and produce mAbs for the treatment of many diseases. Let’s look first at the structure of a protein starting at the basic subunit, an amino acid.
Amino Acids
There are hundreds of different amino acids that exist, but only 20 are used in building proteins needed for the human body.
Peptides & Proteins
Amino acids can be assembled in chains by connecting the “amino” end of one amino acid to the “acid” end of another.
Molecules consisting of two or more connected amino acids are referred to as peptides while long linear chains of amino acids are called polypeptides. Polypeptides that fold into three dimensional structures are called proteins. A protein can consist of more than one polypeptide.
A protein has a defined structure that gives it a specific reactivity and function in the body.
Peptide:
The “R” groups define each amino acid. They can all be the same or different.
Types of Proteins
- Digestive enzymes like amylase and lipase are produced by the pancreas.
- The hormone thyroxin is produced by the thyroid gland.
- A transport protein like hemoglobin is produced by bone marrow.
- Defense proteins like antibodies (immunoglobins) produced by B cells.
The body can do amazing things like make and use proteins—let’s look next at how antibodies work!
How do monoclonal antibodies work?
So, monoclonal antibodies are specialized proteins — what does that mean — what do they do?
Antigens and Antibodies
Antigens are substances that induce an immune response in the body. Some examples are toxins, bacteria and viruses. Antigens exist on the surface of cells of the body as well and mark a cell as not harmful (“self”) or harmful (such as a cell infected with a virus).
If you test positive for an antigen test, this means you have an active infection (the antigen is present in your body).
Antibodies are proteins produced by the immune system to protect the body from foreign substances (antigens). They bind to these substances and facilitate their elimination, thus protecting us from the antigen.
If you test positive for an antibody test, this means you have been infected (currently or previously) and your body reacted by producing antibodies to that antigen.
mAb (monoclonal antibody)
mAbs are proteins manufactured by bioprocessing using specialized cells to produce a specific protein. An individual cell line is developed to produce a specific mAb that will bind to a particular receptor (the antigen). The result can be that an inflammation pathway is disrupted, a cell is destroyed by the load the mAb brings in the form of a potent molecule that disrupts cancer cells’ replication pathway (Elahere) or cancer cells are destroyed by the T cells the mAb brings in proximity to the cancer cells.
More mAbs!
Stay tuned for more issues on mAbs where we will explore the details on the different types of mAbs, how they work, and how we make and purify them!
