Monoclonal Antibodies - Stellar IAS Academy

Human body’s immune system attacks foreign substances by making a large numbers of antibodies. An antibody is a protein that is formed in response to a specific protein on the and sticks to it, the latter referred to as an antigen. Antibodies circulate throughout the body in the blood plasma until they find and attach to this specific antigen. Once attached, they enforce other parts of the immune system to destroy the cells containing the antigen.Monoclonal antibodies are molecules engineered in the laboratory to serve as substitute antibodies that can restore, enhance, or mimic the immune system’s attack on cells.

Antibodies, known as immunoglobulins, are produced by B cells (plasma cells) to neutralize antigens

What are Monoclonal Antibodies?

Monoclonal antibodies are molecules engineered in the laboratory to serve as substitute antibodies that can restore, enhance, or mimic the immune system’s attack on cells.Scientists can design antibodies that specifically target a certain antigen, such as one found on cancer cells. They can then make many copies of that antibody in the lab that are designed to bind to the selected antigens.These antigens are more numerous on the ‘diseased’ cell than the healthy cell.

It was in 1975 that Cesar Milstein and Georges Köhler developed technique for making monoclonal antibodies.They were awarded the Nobel Prize in 1982.

Israel’s Institute for Biological Research Institute (IIBRI) has identified an antibody that neutralizes SARS-CoV-2 in vitro or outside of a living organism.Similar feats have been reported by scientists in other countries such as Netherlands.

This is a significant step in the fight against COVID-19 because the scientists developed it from a single recovered cell, hence, the term monoclonal antibody. This means that the antibody is more potent in developing an effective treatment as compared to the antibodies that have been extracted across the globe are all polyclonal.

Monoclonal antibodies are used to treat many diseases, including some types of cancer. To make a monoclonal antibody, researchers first have to identify the right antigen to attack.The first therapeutic use in humans took place in 1982 to treat a lymphoma.

Scientists are of the opinion that Monoclonal Antibodies will be the bridge toward longer immunity, which will be conferred by vaccines.

Pros of Monoclonal Antibody Therapy:

1.They are quicker to develop to target a disease than vaccines.

2.They function rapidly.

3.Their safety is theoretically easier to predict

Cons:

1.Higher cost especially when sufficient product is needed to evoke response.

2.Time consuming – any where between 6 months -9 months.

3.Very expensive and needs considerable efforts to synthesize them.

Steps in Production of Monoclonal Antibodies:

Monoclonal antibodies (mAbs) are produced by injecting an antigen to a mouse, which causes production of antibodies by it’s immune system and then fusing polyclonal B cells from the mouse’s spleen to myeloma cells. The resultant hybridoma cells are cultured and they continue to produce antibodies to the antigen.

What are Polyclonal Antibodies?

Whereas monoclonal antibodies come from a single cell lineage),polyclonal antibodies are secreted by different B cell lineages within the body.

These are a collection of immunoglobulin molecules that react to a specific antigen, each identifying a different epitope and can recognize and bind to many different epitopes of a single antigen.

Polyclonal antibodies are produced by injecting an antigen into an animal. To produce higher titers of antibodies against the particular antigen, the animal is given a secondary even tertiary immunization, after being injected with a specific antigen to elicit a primary immune response.

Polyclonal antibodies can now be obtained straight from the serum or purified to obtain a solution which is free from other serum proteins.

Important Topics Prelims 2020