IL-1 alpha Protein, Human

IL-1 alpha is a ubiquitous and pivotal pro-inflammatory cytokine. IL-1 alpha is produced by monocytes and macrophages as a proprotein, which is proteolytically processed and released in response to cell injury, and thus induces apoptosis. IL-1 alpha plays an important role in inflammation and bridges the innate and adaptive immune systems. IL-1 alpha mediates the activation of NF-kappa-B and the three MAPK pathways p38, p42/p44 and JNK pathways^[1][4]. IL-1 alpha protein, Human is a recombinant protein consisting of 159 amino acids (S113-A271) and is produced by E. coli.

IL-1 alpha (interleukin-1 alpha) is a major agonist of IL-1. IL-1α is present in all mesenchymal cells in particular, cells rich in IL-1α constitute tissues with a barrier function, such as keratinocytes in the skin, type 2 epithelial cells in the lung, the epithelium of the entire gastrointestinal tract, endothelial cells in blood vessels, and astrocytes in the brain^[1]. The precursor of IL-1α (ProIL-1α) is processed by the Ca²⁺-dependent protease calpain (including caspase-1) into the mature 17 kDa form and the 16 kDa N-terminal cleavage product – the propiece of IL-1α, also termed IL-1α N-terminal peptide (IL-1NTP). The latent form of calpain is activated in cells under inflammatory conditions and especially upon loss of plasma membrane integrity, which occurs during necrosis. pro-IL-1α and mature IL-1α bind to IL-1R and induces the secretion of IL-6 and TNF^[5]. IL-1α acts as an ‘alarmin’ and as a primum movens of tissue inflammation^[1]. IL-1 alpha trigger inflammation in a pathway initiated through Myd88 activation and culminated in NF-κB–induced transcription of inflammatory genes^[2]. IL-1 alpha inhibits differentiation of preadipocytes and lipid accumulation^[3]. IL-1 alpha induces apoptosis and inhibits the osteoblast differentiation^[4].

IL-1 alpha (0.5, 1, 2.5, 5, 10 ng/mL; 5 days) significantly reduces the cell viability in MC3T3-E1 cells^[4].
IL-1 alpha (0.5, 1, 2.5, 5, 10 ng/mL 24 h) decreases the ALP and caspase-3 activity in MC3T3-E1 cells, increases the expression of Bax and caspase-3 mRNA and protein level in a dose-dependent manner, decreases the mRNA expression and the protein levels of Runx2, ALP, OSX and OCN; induces apoptosis^[4].

IL-1 alpha (10 µg/kg; i.p.) significantly increases the TG (triglyceride) level at 12 h in serum in C57BL/6J male mice^[3].
IL-1 alpha (1, 10, 100 ng/mL; 8 days) inhibits differentiation of preadipocytes and lipid accumulation in a dose-dependent manner in 3T3-L1 cells^[3].

1.The ED₅₀ is <1.0 pg/mL as measured by murine D10S cells, corresponding to a specific activity of >1.0 × 10⁹ units/mg.
2.Measured in a cell proliferation assay using CTLL-2 cells. The ED₅₀ for this effect is 10.95 pg/mL, corresponding to a specific activity is 91.32×10⁶ units/mg.
3.Measured by its ability to down regulate the expression of CCN2 in NIH-3T3 mouse embryonic fibroblast cells. The ED₅₀ for this effect is 20.03-24.05 pg/mL, corresponding to a specific activity is 4.158-4.992×10⁷ U/mg.

• 
  Measured in a cell proliferation assay using CTLL-2 cells. The ED₅₀ for this effect is 10.95 pg/mL，corresponding to a specific activity is 91.32×10⁶ units/mg.

Human

E. coli

Tag Free

P01583 (S113-A271)

3552  [NCBI]

SAPFSFLSNVKYNFMRIIKYEFILNDALNQSIIRANDQYLTAAALHNLDEAVKFDMGAYKSSKDDAKITVILRISKTQLYVTAQDEDQPVLLKEMPEIPKTITGSETNLLFFWETHGTKNYFTSVAHPNLFIATKQDYWVCLAGGPPSITDFQILENQA

Approximately 20 kDa

• 
  Greater than 95% as determined by reducing SDS-PAGE.

Lyophilized powder

Lyophilized after extensive dialysis against PBS, pH 7.4 or 20 mM Tris-HCl, 150 mM NaCl, pH 7.5 or 50 mM Tris-HCL, 300 mM NaCL, 200 mM arginine, pH 8.0 or PBS, pH 7.4, 8% trehalose.

<1 EU/μg, determined by LAL method.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O. For long term storage it is recommended to add a carrier protein (0.1% BSA, 5% HSA, 10% FBS or 5% Trehalose).

Stored at -20°C for 2 years. After reconstitution, it is stable at 4°C for 1 week or -20°C for longer (with carrier protein). It is recommended to freeze aliquots at -20°C or -80°C for extended storage.

Room temperature in continental US; may vary elsewhere.

• [1]. Cavalli G, et al. Interleukin 1α: a comprehensive review on the role of IL-1α in the pathogenesis and treatment of autoimmune and inflammatory diseases. Autoimmun Rev. 2021 Mar;20(3):102763.  [Content Brief]

  [2]. Wu T, et al. Involvement of p38 and p42/44 MAP kinases and protein kinase C in the interferon-gamma and interleukin-1alpha-induced phosphorylation of 85-kDa cytosolic phospholipase A(2) in primary human bronchial epithelial cells. Cytokine. 2004 Jan 7;25(1):11-20.  [Content Brief]

  [3]. Um JY, et al. Functional polymorphism of IL-1 alpha and its potential role in obesity in humans and mice. PLoS One. 2011;6(12):e29524.  [Content Brief]

  [4]. Guo C, et al. IL-1α induces apoptosis and inhibits the osteoblast differentiation of MC3T3-E1 cells through the JNK and p38 MAPK pathways. Int J Mol Med. 2016 Jul;38(1):319-27.  [Content Brief]

  [5]. Malik A,et al. Function and regulation of IL-1α in inflammatory diseases and cancer. Immunol Rev. 2018 Jan;281(1):124-137.  [Content Brief]