Klotho beta, a divergent structural member of the glycosidase I superfamily, is expressed primarily in the liver and pancreas, with lower expression in adipose tissue. It is mapped to chromosome 4. The Klotho beta mediated interaction of human FGF19 (mouse FGF15) with FGF Receptor 4 in the liver negatively regulates bile acid synthesis by controlling the secretion of two key bile acid synthase genes, cholesterol 7-alpha hydroxylase (Cyp7a1) and sterol 12-alpha hydroxylase (Cyp8b1). Klotho beta is also an essential cofactor for FGF21 activity and the Klotho gene family may have evolved to confer tissue-specific bioactivity on FGF19 subfamily members. Sample Type: Cell lysates, cell culture supernates, serum, plasma (Heparin or EDTA). Intended Use: Sandwich High Sensitivity BioAssay(TM) ELISA kit for Quantitative Detection of Human Klotho beta. Sensitivity: <10pg/ml Range: 31.2pg/ml-2000pg/ml Specificity: Recognizes natural and recombinant Human Klotho beta. There is no detectable cross-reactivity with other relevant proteins. Test Principle: This Human Klotho beta BioAssay(TM) ELISA Kit was based on standard sandwich enzyme-linked immune- sorbent assay technology. A monoclonal antibody from mouse specific for Klotho beta has been precoated onto 96-well plates. Standards(Expression system for standard: NSO, Immunogen sequence: F53-L997) and test samples are added to the wells, a biotinylated detection polyclonal antibody from goat specific for Klotho beta is added subsequently and then followed by washing with PBS or TBS buffer. Avidin-Biotin-Peroxidase Complex was added and unbound conjugates were washed away with PBS or TBS buffer. HRP substrate TMB was used to visualize HRP enzymatic reaction. TMB was catalyzed by HRP to produce a blue color product that changed into yellow after adding acidic stop solution. The density of yellow is proportional to the Human Klotho beta amount of sample captured in plate. Kit Components: 96-well plate precoated with anti-Human KLB antibody, 1x plate Lyophilized recombinant Human KLB standard, 2x10ng/tube Biotinylated anti-Human KLB antibody, 1x130ul (dilution 1:100) Avidin-Biotin-Peroxidase Complex (ABC), 1x130ul (dilution 1:100) Sample diluent buffer, 1x30ml Antibody diluent buffer, 1x12ml ABC diluent buffer, 1x12ml TMB color developing agent, 1x10ml TMB stop solution, 1x10ml PBS washing buffer Powder for 1000ml, 1x buffer Storage and Stability: Store powder at 4C liquid at -20C. Store other components at 4C. Stable for at least 6 months For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
