IL1F5 Full-Length MS Protein Standard (NP_775262), Labeled with [U- 13C6, 15N4]-L-Arginine and [U- 13C6, 15N2]-L-Lysine, was produced in human 293 cells (HEK293) with fully chemically defined cell culture medium to obtain incorporation efficiency at Creative-Proteomics. The protein encoded by this gene is a member of the interleukin 1 cytokine family. This cytokine was shown to specifically inhibit the activation of NF-kappaB induced by interleukin 1 family, member 6 (IL1F6). This gene and eight other interleukin 1 family genes form a cytokine gene cluster on chromosome 2. Two alternatively spliced transcript variants encoding the same protein have been reported.