Human CD40 Ligand/TNFSF5 Quantikine ELISA Kit Summary

Product Summary

The Quantikine Human CD40 Ligand Immunoassay is a 4.5 hour solid-phase ELISA designed to measure human CD40 Ligand in cell culture supernates, serum, and plasma. It contains E. coli-expressed recombinant human CD40 Ligand and has been shown to accurately quantitate the recombinant factor. Results obtained using natural human CD40 Ligand 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 human CD40 Ligand.

Preparation and Storage

Background: CD40 Ligand/TNFSF5

CD40 Ligand, also known as TNFSF5, CD154, TRAP, and gp39, is a trimeric protein that is expressed in transmembrane and soluble forms. It is expressed by many immune cell types as well as by endothelial and smooth muscle cells of the vasculature. It binds to CD40 on antigen presenting cells, platelets, and endothelial and epithelial cells, leading to enhanced B cell activation and T cell dependent humoral immune responses. CD40 Ligand dysregulation contributes to immune pathology in AIDS, atherosclerosis, atherothrombosis, and restenosis.

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.