Interleukin-11, also known as adipogenesis inhibitory factor (AGIF) and oprelvekin, is a member of the GP130 family of cytokines. These cytokines drive the assembly of multi-subunit receptor complexes containing at least one GP130. IL-11 exerts biological activity through IL-11 receptor by utilizing the gp130 molecule as the signaling component of its receptor. Interleukin 11 (IL-11) is a highly conserved precursor protein of 19kDa with 199 amino acids. The first 21 amino acids are a typical leader sequence for secreted proteins. When the 178 amino acid protein is released from the cell, the first 21 amino acids are removed. IL-11 is thermally stable and contains no cysteine residues. Many cell and tissue types throughout the body, such as CNS, thymus, lung, bone, connective tissues, uterus, skin, and testis, can produce IL-11 depending on the local environment of the cell or tissue. IL11 promotes primary and secondary immune responses in vitro and in vivo and modulates antigen-specific antibody reactions. IL-11 has activity in bone metabolism and activity in protection and restoration of the gastrointestinal mucosa. Human endometrial stromal cells produce biologically activeIL-11, which promotes progesterone-induced decidualization. Therefore, the IL-11 has both paracrine and autocrineactions on human endometrial stromal cells and plays an importantrole in preparing the human endometrium for implantation. Reports indicate that abnormal IL-11 levels in serum or plasma is related to immune thrombocytopenia, rheumatoid arthritis, and urogenital infection. Immunoreactive IL-11 has also been linked to aseptic loosening of total hip replacement implants. The production of IL-11 is elevated in lesional skin organ cultures of patients with active plaque-type psoriasis as compared with non-lesional and normal skin. The human IL-11 genes contain five exons, each having a length of 7 kDa, and are mapped to chromosome 19q13. 3-13. 4. Primate and human IL-11 sequences show 97 percent homology. The human IL-11 receptor gene maps to chromosome 9p13. This IL-11 ELISA Kit is a ready-to-use 3.5-hour solid phase immunoassay capable of measuring IL-11 levels in serum, plasma, cell culture supernatant in the range of 0 to 1600 pg/mL. This kit has been shown to have a specific reaction with IL-11 without any cross reactivity with various other cytokine super-family proteins.