< 0.5% cross-reactivity observed with available related molecules.Cross-species reactivity not tested.
No significant interference observed with available related molecules.
The Quantikine Human PAPP-A Immunoassay is a 5.5 hour sandwich-type solid phase ELISA designed to measure human PAPP-A in cell culture supernates, serum, and plasma. It contains NS0-expressed recombinant human PAPP-A and has been shown to accurately quantitate the recombinant factor. Results obtained using natural human PAPP-A showed linear 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 naturally occurring PAPP-A.
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 PAPP-A spiked to 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 PAPP-A were serially diluted in 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.
Pappalysins comprise one of the five families of Metzincins (other families include ADAMs/ADAMTSs, MMPs, Astacins, and Serralysins). Pappalysin-1 (PAPP-A) is an important pregnancy protein and increases in plasma by a factor of about 150 during pregnancy. Reduced maternal serum PAPP-A is a major marker of Down syndrome in the first trimester of pregnancy. PAPP-A cleaves IGFBP-4 and -5 (insulin-like growth factor-binding protein-4 and 5) at a single site, resulting in the release of bioactive IGF. Pappalysin-2 (PAPP-A2; also called PAPP-E) shares 45% amino acid identity with PAPP-A and cleaves IGFBP-2.
Pregnancy-associated Plasma Protein 1
Entrez Gene IDs
ASBABP2; DIPLA1; EC 184.108.40.206; IGFBP-4ase; IGFBP-4aseaspecific BCL2 ARE-binding protein 2; IGF-dependent IGFBP-4 protease; insulin-like growth factor-dependent IGF binding protein-4 protease; Insulin-like growth factor-dependent IGF-binding protein 4 protease; PAPA; PAPPA; PAPPA1; PAPP-A1; PAPP-Adifferentially placenta 1 expressed protein; Pappalysin1; pappalysin-1; pregnacy-associated plasma protein A; Pregnancy-associated plasma protein A; pregnancy-associated plasma protein A, pappalysin 1;
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.
50 µL Standard, Control, or Sample
Add 50 µL of Standard, control, or sample to each well within 15 minutes. Cover with a plate sealer, and incubate at room temperature for 3 hours.
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.
Aspirate and wash 4 times.
200 µL Substrate Solution
Add 200 µL Substrate Solution to each well. Incubate at room temperature for 30 minutes. 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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but also provides information about sample types, species, and experimental conditions.