View the slide viewer

Have questions about this assay kit?

Human FGFR/α-Klotho Reporter Assay Kit

1 x-96 well format assays
1 x-384 well format assays
1 x-384 well format assays
1 x-96 well format assays

Product Description and Product Data

This is an all-inclusive cell-based luciferase reporter assay kit targeting the Human Fibroblast Growth Factor Receptor 1c and α-Klotho (FGFR/α-Klotho). INDIGO’s FGFR/α-Klotho reporter assay utilizes proprietary mammalian cells that have been engineered to provide constitutive expression of the Human Fibroblast Growth Factor Receptor 1c and α-Klotho. In addition to FGFR/α-Klotho Reporter Cells, this kit provides two optimized media for use during cell culture and in diluting the user’s test samples, a reference agonist, Luciferase Detection Reagent, and a cell culture-ready assay plate. The principal application of this assay is in the screening of test samples to quantify any functional activity, either agonist or antagonist, that they may exert against human FGFR/α-Klotho. This kit provides researchers with clear, reproducible results, exceptional cell viability post-thaw, and consistent results lot to lot. Kits must be stored at -80C. Do not store in liquid nitrogen. Note: reporter cells cannot be refrozen or maintained in extended culture.


  • Ready to Use Upon Receipt

  • Includes All Needed Components
  • Contains Transfected Reporter Cells
  • Eliminates Cell Licensing Fees
  • Clear, Reproducible Results
  • Consistent Results Lot to Lot

Product Specifications

Target TypeGrowth Factor Receptor
Receptor FormHybrid
Assay ModeAgonist, Antagonist
Kit Components
  • FGFR/α-Klotho Reporter Cells
  • Cell Recovery Medium (CRM)
  • Compound Screening Medium (CSM)
  • FGF-23, (ref. activator; in PBS/0.1% BSA )
  • Detection Substrate
  • Detection Buffer
  • White, sterile, cell-culture ready assay plate
Shelf Life6 months
Shipping RequirementsDry Ice
Storage temperature-80C


Activation of FGFR1c/α-Klotho. Activation assays were performed using the reference activator FGF-23 (Prospecbio; provided). The absence of activity by the β-Klotho-dependent endocrine activators FGF-19 and FGF-21 (Peprotech) demonstrates assay specificity.
Inhibition of FGFR1c/α-Klotho. FGFR1c/α-Klotho cells were treated with an EC80 concentration of the reference activator FGF-23 and varying concentrations of the FGFR inhibitors JNJ-4275293, FIIN-3, BGJ398, PD173074, and CH5183284 (all compounds obtained from Cayman Chemical). Live Cell Multiplex (LCM) Assay confirmed that no treatment concentrations were cytotoxic (data not shown).

Target Background

The family of Fibroblast Growth Factors (FGFs) comprise approximately 23 members that are related by core sequence and structure conservation, with the majority of FGFs being secreted signaling proteins. Secreted FGFs are predominantly autocrine and paracrine factors, with only three members evolved to function as endocrine factors. Paracrine FGFs show high affinity towards the extracellular matrix (ECM) component heparin sulfate (HS) and are thus retained in the ECM and function locally. In contrast, the atypical endocrine subfamily of FGFs, that comprise FGF-19, FGF-21, and FGF-23, have reduced affinity for HS and can therefore escape from the ECM into the circulation to distant reach target distant organs.

FGFs bind and activate FGF Receptors (FGFRs) which, themselves, are members of the family of high-affinity tyrosine kinase receptors. The endocrine FGF-23 activates the receptor complex FGFR1c and its co-receptor α-Klotho (FGFR1c/α-Klotho). FGF-23 is a principal regulator in the maintenance of serum phosphorus concentration by inhibiting renal tubular phosphate reabsorption. Unfortunately, various FGF-23-mediated disorders exist. The most common of these is X-linked hypophosphoatemia (XLH). Additional disorders of FGF-23 signaling include autosomal dominant and recessive hypophosphophatemic rickets, fibrous dysplasia, and tumor-induced osteomalacia. Consequently, FGF-23 and FGFR1c/α-Klotho command considerable interest as therapeutic targets in drug development and drug safety screening.

Also available as a service

Fibroblast Growth Factor Receptor 1c and α-Klotho (FGFR/α-Klotho)

Have questions about this assay kit?