With reference to monoclonal antibodies, often mentioned in news, consider the following statements:

I. They are man-made proteins.

I. They stimulate immunological function due to their ability to bind to specific antigens.

III. They are used in treating viral infections like that of Nipah virus.

Which of the statements given above are correct?

  • I and II only
  • II and III only
  • I and III only
  • I, II and III

Answer: (d) I, II and III

Monoclonal antibodies (mAbs)
  • Monoclonal antibodies (mAbs) are lab-made, identical proteins designed to function like natural antibodies, targeting specific antigens on cells to treat diseases like cancer, autoimmune disorders, and infections.
  • They work by binding to specific targets to block growth, tag cells for destruction by the immune system, or deliver treatments directly to cancer cells.
  • Scientists produce them by cloning a single white blood cell (B-cell) that produces a desired antibody. Since all the antibodies are copies (clones) of one original cell, they are called monoclonal antibodies.
  • These proteins are designed to mimic the immune system’s ability to fight off harmful pathogens such as viruses and bacteria.
  • Monoclonal antibodies are highly specific – they are engineered to bind to a particular antigen (a molecule or protein found on the surface of pathogens or abnormal cells). This binding can:
    • Neutralize the pathogen (by blocking its activity),
    • Mark it for destruction by other immune cells,
    • Or block receptors that the virus uses to enter human cells.
  • By binding to these specific targets, mAbs enhance the immune response and help the body fight disease more effectively.
  • Monoclonal antibodies have been developed as therapeutic options for several viral infections, including:
    • COVID-19 (e.g., Casirivimab and Imdevimab)
    • Ebola virus (e.g., Inmazeb, Ebanga)
    • Nipah virus: A monoclonal antibody called m102.4 has shown potential against the Nipah virus. It was used under compassionate use protocols in a few cases and is under further clinical investigation.
monoclonal antibodies

How They Work

  • Targeted Therapy: mAbs are designed to bind to a specific antigen (like a key fitting a lock), such as those on cancer cells.
  • Immune System Support: They act as a marker for cancer cells, allowing the immune system to recognise and destroy them.
  • Blocking Action: They can prevent viruses or bacteria from entering cells, a technique used in treatments for infections.
  • Direct Delivery: Some carry radioactive substances or drugs directly to cancer cells.

Key Medical Applications

  • Cancer Treatment: Common treatments include targeting HER2 in breast cancer (e.g., Trastuzumab) or CD20 in lymphomas (e.g., Rituximab).
  • Autoimmune Diseases: Used to manage conditions like Rheumatoid Arthritis and Crohn’s Disease.
  • Infections: Used for treatments against severe COVID-19 or RSV.
  • Other Conditions: Including migraines, high cholesterol, and asthma.