IL-1 receptor antagonist

They have a natural antagonist IL-1Ra (IL-1 receptor antagonist).

Intrathecal injection of antiserum against dynorphin A (1-17) and IL-1 receptor antagonist significantly inhibited the cancer-induced hyperalgesia.

DIRA (deficiency of the IL-1 receptor antagonist)

IL-1 receptor antagonist and IL-1β treatment Human IL-1Ra or IL-1β was delivered as a recombinant protein or by expression of its cDNA from genetically modified cells.

In patients with rheumatoid arthritis the natural IL-1 receptor antagonist is not found in effective concentrations in synovium and synovial fluid to counteract the elevated IL-1 concentrations in these patients.

So, there was an effort to block IL-1 activity by natural IL-1 receptor antagonist (IL-1Ra), also familiar by its generic name anakinra, but in the end the control trials did not reached statistical significance.