Oligomeric forms of natural and recombinant human Dkk-1
< 0.5% cross-reactivity observed with available related molecules.< 50% cross-species reactivity observed with species tested.
No significant interference observed with available related molecules.
The Quantikine Human Dkk-1 immunoassay is a 4.5 hour solid phase ELISA designed to measure human Dkk-1 in cell culture supernates, serum, and plasma. It contains Sf 21-expressed recombinant human Dkk-1 and has been shown to accurately quantitate the recombinant factor. Results obtained using natural human Dkk-1 showed dose-response curves that were parallel to the standard curves obtained using the Quantikine kit standards. These results indicate that this kit can be used to determine relative mass values of naturally occurring human Dkk-1.
Intra-Assay Precision (Precision within an assay) Three samples of known concentration were tested on one plate to assess intra-assay precision.
Inter-Assay Precision (Precision between assays) Three samples of known concentration were tested in separate assays to assess inter-assay precision.
The recovery of Dkk-1 spiked to various levels throughout the range of the assay was evaluated.
Average % Recovery
Cell Culture Media (n=4)
EDTA Plasma (n=4)
Heparin Plasma (n=4)
To assess the linearity of the assay, samples containing and/or spiked with high concentrations of natural Dkk-1 were serially diluted with the appropriate Calibrator Diluent to produce samples with values within the dynamic range of the assay.
Preparation and Storage
Store the unopened product at 2 - 8 °C. Do not use past expiration date.
Members of the dickkopf-related protein family (Dkk-1, -2, -3, and -4) are secreted proteins with two cysteine-rich domains separated by a linker region. Dkk-3 and -4 also have one prokineticin domain. Dkk-1, -2, and -4 function as antagonists of canonical Wnt signaling by binding to LRP5/6, preventing interaction of LRP5/6 with Wnt-Frizzled complexes. Dkk-1, -2, and -4 also bind cell surface Kremen-1 or -2 and promote the internalization of LRP5/6. Antagonistic activity of Dkk-3 has not been demonstrated. Dkk proteins have distinct patterns of expression in adult and embryonic tissues and have a wide range of effects on tissue development and morphogenesis. The Dkk family also includes Soggy, which is homologous to Dkk-3 but not to the other family members. Soggy has not been shown to inhibit Wnt signaling, and its role in the pathway is unclear.
Refer to the product for complete assay procedure.
Bring all reagents and samples to room temperature before use. It is recommended that all samples, standards, and controls be assayed in duplicate.
Prepare all reagents, standard dilutions, and samples as directed in the product insert.
Remove excess microplate strips from the plate frame, return them to the foil pouch containing the desiccant pack, and reseal.
100 µL Assay Diluent
Add 100 µL of Assay Diluent to each well.
100 µL Standard, Control, or Sample
Add 100 µL of Standard, control, or sample to each well. Cover with a plate sealer, and incubate at room temperature for 2 hours on a horizontal orbital microplate shaker.
Aspirate each well and wash, repeating the process 3 times for a total of 4 washes.
200 µL Conjugate
Add 200 µL of Conjugate to each well. Cover with a new plate sealer, and incubate at room temperature for 2 hours on the shaker.
Aspirate and wash 4 times.
200 µL Substrate Solution
Add 200 µL Substrate Solution to each well. Incubate at room temperature for 30 minutes on the benchtop. PROTECT FROM LIGHT.
50 µL Stop Solution
Add 50 µL of Stop Solution to each well. Read at 450 nm within 30 minutes. Set wavelength correction to 540 nm or 570 nm.
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