- Interleukin 1 or IL-1 is a cytokine upstream of IL-6 in the proinflammatory cascade and leads to IL-6 production through nuclear factor NF-kB signaling.
- IL-1 and IL-6 may both be overexpressed in iMCD because of a common aberrant upstream regulator, such as NF-kB, or up-regulated IL-1, in turn inducing IL-6.
- IL-1 was expressed at elevated levels in 5 cases of HHV-8 unknown multicentric Castleman disease.
- Anakinra, an anti-IL-1 receptor antagonist, has been reported to be effective in several patients, some of whom did not respond to anti-IL-6 therapy.
- A patient who did not respond to anti-IL-6 therapy had a complete response to anti-IL-1 therapy in one case report.