< 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 Mouse/Rat SOST immunoassay is a 4.5 hour solid-phase ELISA designed to measure SOST in mouse or rat cell culture supernates, serum, and plasma. It contains NS0-expressed recombinant mouse SOST and antibodies raised against the recombinant factor. This immunoassay has been shown to accurately quantitate the recombinant mouse SOST. Results obtained using natural mouse or rat SOST 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 for natural SOST.
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 SOST spiked to levels throughout the range of the assay in various matrices was evaluated.
Average % Recovery
Cell Culture Samples (n=4)
Mouse EDTA Plasma (n=4)
Mouse Heparin Plasma (n=4)
Mouse Serum (n=4)
Rat EDTA Plasma (n=2)
Rat Heparin Plasma (n=2)
Rat Serum (n=4)
To assess the linearity of the assay, samples containing and/or spiked with high concentrations of SOST in each matrix were diluted with Calibrator Diluent and assayed.
Preparation and Storage
Store the unopened product at 2 - 8 °C. Do not use past expiration date.
SOST, also known as Sclerostin, is a Cerberus/DAN family BMP antagonist and is an important regulator of bone homeostasis. Inactivating mutations in the SOST gene can cause sclerosteosis and van Buchem disease. SOST is expressed by terminally differentiated cells embedded in mineralized matrix including osteocytes, hypertrophic and prehypertrophic chondrocytes, and tooth cementocytes. Its expression is induced by BMP-2, -4, and -6 and is inhibited by parathyroid hormone (PTH). Its downregulation in osteocytes by physical loading of bone contributes to the mechanical sensor function of osteocytes and the subsequent increase in bone growth. SOST binds to BMP-2, -4, -5, -6, and -7 and inhibits the osteogenic differentiation induced by these BMPs. It inhibits canonical Wnt signaling by binding to LRP-5 and LRP-6 and inhibiting their association with Frizzled receptors. SOST reduces the proliferation of mesenchymal stem cells (MSC) and induces MSC apoptosis. Circulating levels of SOST are elevated in pathologies with bone involvement including low bone mineral density, Paget’s disease, multiple myeloma, and prostate cancer with bone metastases. It is also elevated in advanced chronic kidney disease, alcoholic liver disease, type 2 diabetes, and patients with increased abdominal and gynoid fat.
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, control, 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.
50 µL Assay Diluent
Add 50 µL of Assay Diluent to each well.
50 µL Standard, Control, or Sample
Add 50 µL of Standard, control, or sample to each well. Cover with a plate sealer, and incubate at room temperature for 3 hours.
Aspirate each well and wash, repeating the process 4 times for a total of 5 washes.
100 µL Conjugate
Add 100 µL of Conjugate to each well. Cover with a new plate sealer, and incubate at room temperature for 1 hour.
Aspirate and wash 5 times.
100 µL Substrate Solution
Add 100 µL Substrate Solution to each well. Incubate at room temperature for 30 minutes. PROTECT FROM LIGHT.
100 µL Stop Solution
Add 100 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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but also provides information about sample types, species, and experimental conditions.