INTENDED USE

This Human IL-8 ELISA kit is to be used for the in vitro quantitative determination of human interleukin-8 (IL-8) 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-8 (IL-8), also known as neutrophil attractant/activating protein (NAP-1), monocyte-derived neutrophil-activating peptide (MONAP), monocyte-derived neutrophil chemotactic factor (MDNCF), T lymphocyte chemotactic factor (TCF) and leukocyte adhesion inhibitor (LAI), is a member of the chemokine superfamily which selectively chemoattract and activate specific leukocyte subpopulations (1,2). All of these cytokines have four conserved cysteines and two distinguishable subfamilies. These two subfamilies are dependent on the position of the first two cysteines, which are either separated by on amino acid (C-X-C proteins) or are adjacent (CC-protein) to each other. The members of the two subfamilies differ in their target cell selectivity as well as the chromosomal location of their genes (chromosome 4 for the C-X-C proteins and chromosome 17 for the C-C proteins). IL-8 belongs to the C-X-C subfamily along with platelet factor 4 (PF4), platelet basic protein (PBP), connective-tissue-activating peptide III (CTAPIII), b-thromboglobulin, neutrophil-activating peptide-2 (NAP-2), ENA-78 (3), three closely related MGSA/CRO gene products (GRO-a, GRO-b, GRO-g), and g-interferon-inducible protein (g-IP-10)(4). The members of the C-C chemokines are mainly chemotactic for monocytes whereas the C-X-C chemokines except for IP10 and PF4, chemoattract and activate neutrophils. Various non-infectious human diseases are known to be associated with neutrophilia and/or neutrophil infiltration into organs. Examples of some of these human diseases include rheumatoid arthritis, gouty arthritis, psoriasis, glomerulonephritis, adult respiratory distress syndrome, immune vasculitis, inflammatory bowel disease, ischemia-reperfusion syndrome (including myocardial infarction and multiple organ failure), chorioretinitis, cystic fibrosis, septic shock, acute meningococcal infections, alcoholic hepatitis and Mediterranean fever (8). In addition to the effect on neutrophils, IL-8 has been reported to be a less potent chemoattractant for T lymphocytes (5).

IL-8 is produced by many cells in response to inflammatory stimuli such as IL-1b or TNF-a and to various types of mitogen, lectins, crystals, viruses, and phorbol esters (PMA). Many cell types that produce IL-8 in response to these stimuli can include: monocytes/ macrophages, T lymphocytes, neutrophils, fibroblasts, keratinocytes, hepacytes, chondrocytes, endothelial cells, glioblatoma cells, and mesothelial cells (6).

In addition to recruiting and activating neutrophils, IL-8 may elicit many other activities that contribute to diseases. However, IL-8 is not known to trigger systemic inflammatory reactions such as fever, acute phase protein induction.

This IL-8 ELISA is a 2.5 hour solid-phase immunoassay readily applicable to measure IL-8 levels in cell culture supernatant, serum, plasma, and other biological fluids ranging from 0 to 800pg/mL. It has shown no cross-reactivity with human monocyte chemotactic activating factor (MCAF) or RANTES (Regulated on Activation, Normal T-cell Expressed, and Secreted). This IL-8 ELISA is expected to be useful for further investigations into the role of IL-8 in inflammatory reaction and immune response.

CITATIONS

1. Christopher J. Justinich et al. The extracellular calcium-sensing receptor (CaSR) on human esophagus and evidence of expression of the CaSR on the esophageal epithelial cell line (HET-1A). American Journal of Physiology - Gastrointestinal and Liver Physiology Published 1 January 2008Vol. 294no. G120-G129.

2. Ping YF, Yao XH et al. The anti-cancer compound Nordy inhibits CXCR4-mediated production of IL-8 and VEGF by malignant human glioma cells. J Neurooncol. 2007 Aug;84(1):21-9.

3. Yao XH, Ping YF et al. Production of angiogenic factors by human glioblastoma cells following activation of the G-protein coupled formylpeptide receptor FPR. J Neurooncol. 2008 Jan;86(1):47-53.

4. Padron E, Painter JS, Kunigal S, Mailloux AW, McGraw K, McDaniel JM, Kim E, Bebbington C, Baer M, Yarranton G, Lancet J, Komrokji RS, Abdel-Wahab O, List AF, Epling-Burnette PK.GM-CSF-dependent pSTAT5 sensitivity is a feature with therapeutic potential in chronic myelomonocytic leukemia. Blood 2013; 25(121):5068-77.

5. Arismendi E, Rivas E, Vidal J, Barreiro E, Torralba Y, Burgos F, Rodriguez-Roisin R. Airway Hyperresponsiveness to Mannitol in Obesity Before and After Bariatric Surgery. Obes Surg 2015; 9(25):1666-71.

6. Ye BG, Sun HC, Zhu XD, Chai ZT, Zhang YY, Ao JY, Cai H, Ma DN, Wang CH, Qin CD, Gao DM, Tang ZY.Reduced expression of CD109 in tumor-associated endothelial cells promotes tumor progression by paracrine interleukin-8 in hepatocellular carcinoma. Oncotarget 2016; 20(7):29333-45.

7. Guo Y, Shi G, Wan H, Zhou M.Hedgehog signaling regulates the expression levels of inflammatory mediators in cigarette‑induced airway inflammation. Mol Med Rep 2018; 6(17):8557-8563.