Question

Basiliximab is an

• A. IL-1 receptor antagonist
• B. Anti-CD3 antibody
• C. IL-2 receptor antagonist
• D. TNF inhibitor

Answer 1

The Correct Option is C

Basiliximab is a pharmaceutical drug used primarily in clinical settings to prevent transplant rejection, specifically in kidney transplants. It functions by targeting the interleukin-2 receptor (IL-2R) on activated T-lymphocytes. IL-2 receptors are critical for the clonal expansion of T-cells, which play a significant role in the immune response against transplanted organs.

The mechanism of action of basiliximab is as follows:

• Basiliximab acts as an IL-2 receptor antagonist.
• By binding to the alpha subunit (CD25) of the IL-2 receptor on the surface of activated T-cells, it prevents interleukin-2 from binding, thus inhibiting T-cell activation and proliferation.
• This suppression of the immune response reduces the likelihood of the body rejecting the transplanted organ.

Given the options provided:

• IL-1 receptor antagonist
  - This is not the mechanism of action for basiliximab.
• Anti-CD3 antibody
  - This refers to a different class of immunosuppressants that act on T-cells by different mechanisms.
• TNF inhibitor
  - Tumor Necrosis Factor inhibitors are used for conditions like rheumatoid arthritis and are not related to IL-2 receptor blocking.
• IL-2 receptor antagonist - This accurately describes basiliximab's function.

Thus, basiliximab is best classified as an IL-2 receptor antagonist.