INTENDED USE

This Human IL-1b ELISA kit is to be used for the in vitro quantitative determination of human interleukin-1b (IL-1b) concentrations in cell culture supernatant, serum, plasma and other biological fluids. This kit is intended for LABORATORY RESEARCH USE ONLY and is not for use in diagnostic or therapeutic procedures.

INTRODUCTION

Interleukin 1 (IL-1) is considered the first of the super-family of regulatory and inflammatory cytokines. There are two distinct IL-1 proteins: Interleukin 1α and Interleukin 1b. The two forms of IL-1 are distinct gene products; they recognize the same receptor and share biological properties. IL-1 has a number of alternative names, including lymphocyte activating factor, endogenous pyrogen, catabolin, hemopoietin-1, melanoma growth inhibition factor, and osteoclast activating factor. The properties and biological activities of IL-1 have been extensively reviewed. IL-1 is expressed by many cells and has multiple functions including local inflammation. Cells known to express IL-1b include astrocytes, adrenal cortical cells, natural killer (NK) cells, macrophages and monocytes, endothelial cells, keratinocytes, megakaryocytes and platelets, neurons, neutrophils,oligodendroglia, osteoblasts, Schwann cells, trophoblasts, and T cells plus fibroblasts.

The biological properties of IL-1 show some overlap with other cytokines including tumor necrosis factor (TNF) and interleukin 6 (IL-6), which are all capable of stimulating T and B lymphocytes, augmenting cell proliferation and initiating or suppressing gene expression for several proteins. Although IL-1 is generally thought of as a prototypical pro-inflammatory cytokine, the effects of IL-1 are not limited to inflammation. Following bacterial or immunoglobulin ligation of monocyte/macrophage CD14 (the LPS receptor) or CD64 (the IgG receptor), IL-1 can be released into a local environment. Within this environment, IL-1 impacts a number of cells. First, capillary endothelial cells are induced to do two things, one, secrete chemokines such as MCP-1, and two, up-regulate the expression of vascular adhesion molecules such as E-Selectin, ICAM-1 and VCAM-1. MCP-1 provides a stimulus for chemotaxis and activates mononuclear cell integrins, thus facilitating mononuclear infiltration into an area of early inflammation. IL-1 also induces expression of itself in newly arriving monocytes, thus reinforcing the overall process. In terms of other pro-inflammatory molecules, IL-1 apparently is needed for the efficient production of IFN-g. On resident NK cells, IL-1 apparently works in conjunction with macrophage-derived IL-12 to induce IFN-g secretion, resulting in an IFN-g induced activation of macrophages. Finally, IL-1 also induces the expression of MMPs from resident fibroblasts. This function can have at least two effects: first extracellular matrix degradation can facilitate monocyte migration, and second, MMPs are known to degrade IL-1b, thus down-modulating the local inflammatory response initiated by IL-1.

This IL-1b ELISA is a ready-to-use 3.5-hour solid phase immunoassay capable of measuring IL-1b levels in cell culture supernatant, serum, plasma, and other biological fluids in the range of 0 to 400 pg/mL. This assay has shown no cross-reactivity with various other cytokines super-family proteins.

1. Han X, Tao YL, Deng YP, Yu JW, Cai J, Ren GF, Sun YN, Jiang GJ.Metformin ameliorates insulitis in STZ-induced diabetic mice. PeerJ 2017; (5):e3155.

2. He S, Zeng D, Xu F, Zhang J, Zhao N, Wang Q, Shi J, Lin Z, Yu W, Li H.Baseline Serum Levels of Beclin-1, but Not Inflammatory Factors, May Predict Antidepressant Treatment Response in Chinese Han Patients With MDD: A Preliminary Study. Front Psychiatry 2019; (10):378.