Rytvela (Peptide 101.10, d-(RYTVELA)) is a potent, selective, allosteric negative modulator (antagonist) of IL-1 receptor I (IL-1RI), inhibits dose-dependently IL-1-induced PGE2 formation (IC50= 0.5 nM) and IL-1-induced human thymocyte (TF-1 cell) proliferation (IC50=2 nM).
[125I]101.10 binds specifically in a saturable manner with an affinity constant (KD) of 5 nM to thymocytes containing IL-1RI.
Rytvela (Peptide 101.10) diminished maximum TF-1 proliferation induced by IL-1 with an estimated pA2 value of 5 nM.
Rytvela (Peptide 101.10) is selective for IL-1, and inactive agqainst homologous cytokine of the IL-1 family IL-18.
Rytvela (Peptide 101.10) demonstrated robust in vivo effects in models of hyperthermia and inflammatory bowel disease as well as topically in contact dermatitis, superior to corticosteroids and IL-1ra; Rytvela (Peptide 101.10) did not bind to IL-1RI deficient cells and was ineffective in vivo in IL-1RI knockout mice.