IL-13 Protein, Human

IL-13 is a multifunctional cytokine. IL-13 activates the JAK-STAT6 signaling pathway and regulates gene expression by binding to the type II IL-4 receptor complex (IL-4Rα/IL-13Rα1) on the cell surface. IL-13 can induce monocyte CD23 expression, B cell IgE synthesis, fibroblast eotaxin secretion, and enhanced calcium flux in airway smooth muscle cells. IL-13 promotes airway inflammation in mice. IL-13 Protein, Human is a recombinant IL-13 protein expressed by E. coli without a tag.

IL-13 belongs to the interleukin (IL) family^[1]. IL-13 is a multifunctional cytokine^[1][2][5]. IL-13 binds to the type II IL-4 receptor complex (IL-4Rα/IL-13Rα1) on the cell surface, activates the JAK-STAT6 signaling pathway, and regulates gene expression. Its effects are cell type specific (e.g., dependent on the γc chain in hematopoietic cells and dependent on IL-13Rα1 in non-hematopoietic cells)^[1][5]. IL-13 can induce monocyte CD23 expression, B cell IgE synthesis, fibroblast eotaxin secretion, and enhanced calcium flux in airway smooth muscle cells. IL-13 can promote airway eosinophil infiltration, AHR, and liver fibrosis in mice^[1][3][5]. IL-13 is expressed in a variety of tissues and cells, including immune cells (such as macrophages, monocytes, B cells) and structural cells (such as fibroblasts, airway smooth muscle cells) in the lung, liver, esophagus, etc^[1][3][5]. IL-13, Human has approximately 60% homology with mouse IL-13 in amino acid sequence, but there are species differences in function (such as human IL-13 does not activate mouse IL-13 receptor)^[5]. IL-13, Human is a non-glycosylated protein composed of 132 amino acids with a molecular weight of approximately 10 kDa^[4].

IL-13 Protein, Human (0.8 nM) induces eotaxin-1 production in normal human lung fibroblasts (NHLF)^[5].

IL-13 Protein, Human (2 μg) induces inflammation in the mouse air pouch model, resulting in infiltration of leukocytes and eosinophils^[5].

The cell proliferation assay using human TF-1 cells has an ED₅₀ value of less than 5 ng/mL.

• 
  Measured in a cell proliferation assay using TF-1 human erythroleukemic cells. The ED₅₀ for this effect is 1.195 ng/mL, corresponding to a specific activity is 8.37×10⁵ U/mg.

Human

E. coli

Tag Free

P35225 (G35-N146)

3596  [NCBI]

Partial

GPVPPSTALRELIEELVNITQNQKAPLCNGSMVWSINLTAGMYCAALESLINVSGCSAIEKTQRMLSGFCPHKVSAGQFSSLHVRDTKIEVAQFVKDLLLHLKKLFREGRFN

Approximately 12.3 kDa

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

Lyophilized powder

Lyophilized from a 0.2 μm filtered solution of PBS, pH 7.2, with 5% or 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 from date of receipt. 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]. Junttila IS, et al. Tuning sensitivity to IL-4 and IL-13: differential expression of IL-4Ralpha, IL-13Ralpha1, and gammac regulates relative cytokine sensitivity. J Exp Med. 2008 Oct 27;205(11):2595-608.  [Content Brief]

  [2]. Shimamura T, et al. Novel role of IL-13 in fibrosis induced by nonalcoholic steatohepatitis and its amelioration by IL-13R-directed cytotoxin in a rat model. J Immunol. 2008 Oct 1;181(7):4656-65.  [Content Brief]

  [3]. Blanchard C, et al. Inhibition of human interleukin-13-induced respiratory and oesophageal inflammation by anti-human-interleukin-13 antibody (CAT-354). Clin Exp Allergy. 2005 Aug;35(8):1096-103.  [Content Brief]

  [4]. de Waal Malefyt R, et al. Effects of IL-13 on phenotype, cytokine production, and cytotoxic function of human monocytes. Comparison with IL-4 and modulation by IFN-gamma or IL-10. J Immunol. 1993 Dec 1;151(11):6370-81.  [Content Brief]

  [5]. May RD, et al. Preclinical development of CAT-354, an IL-13 neutralizing antibody, for the treatment of severe uncontrolled asthma. Br J Pharmacol. 2012 May;166(1):177-93.  [Content Brief]