Human DPPIV/CD26 Quantikine ELISA Kit Summary

Product Summary

The Quantikine® Human DPPIV/CD26 Immunoassay is a 4.5 hour solid-phase ELISA designed to measure human DPPIV in cell culture supernates, serum, plasma, saliva, and urine. It contains NS0-expressed recombinant human DPPIV, and antibodies raised against the recombinant factor. Results obtained using natural human DPPIV 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 human DPPIV.

Preparation and Storage

Background: DPPIV/CD26

DPPIV/CD26 is a serine exopeptidase that is expressed as a noncovalent homodimer on the surface of epithelial cells, endothelial cells, and activated lymphocytes. It regulates multiple aspects of immune and endocrine function by cleaving Xaa-Pro or Xaa-Ala dipeptides from the N-terminus of a wide variety of chemokines (CCL4 and 5, CXCL6, 9, 10, 11, and 12), growth factors (GM-CSF, IL-3), and peptide hormones (Glucagon, Glucagon-like Peptides 1 and 2, GIP, GHRH, Procalcitonin, Neuropeptide Y, and Substance P). DPPIV interacts in cis with Adenosine Deaminase on T cells, in trans with Caveolin-1 on antigen presenting cells, and it serves as a cell entry coreceptor for HIV and coronavirus. It provides costimulatory proliferation and activation signals to both CD4+ and CD8+ T cells. A soluble form of DPPIV can be proteolytically shed from adipocytes, leading to insulin resistance in adipocytes and skeletal muscle.

Assay Procedure

Refer to the product datasheet for the 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.

1.     Prepare all reagents, standard dilutions, and samples as directed in the product insert.

2.     Remove excess microplate strips from the plate frame, return them to the foil pouch containing the desiccant pack, and reseal.

3.     Add 50 μL of Assay Diluent to each well.

4.     Add 50 μL of Standard, control, or sample to each well. Cover with a plate sealer, and incubate at room temperature for 2 hours.

5.     Aspirate each well and wash, repeating the process 4 times for a total of 5 washes.

6.     Add 100 μL of Conjugate to each well. Cover with a new plate sealer, and incubate at room temperature for 2 hours.

7.     Aspirate and wash 5 times.

8.     Add 100 μL Substrate Solution to each well.

9.     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.