Human IL-1 RII Quantikine ELISA Kit Summary

Product Summary

The Quantikine Human IL-1 sRII Immunoassay is a 3.5 hour solid phase ELISA designed to measure IL-1 sRII in serum, plasma, and cell culture supernates. It contains insect cell-expressed recombinant human IL-1 sRII and has been shown to quantitate the recombinant factor accurately. Results obtained using natural IL-1 sRII showed linear curves that were parallel to the standard curves obtained using the kit standards. These results indicate that this kit can be used to determine relative mass values for natural IL-1 sRII. The presence of high levels of IL-1 beta (> 7.5 ng/mL) in samples has been found to produce some interference (> 10% change) when assaying samples containing IL-1 sRII in the mid-level range.

Preparation and Storage

Background: IL-1 RII

Two distinct types of receptors that bind the pleiotropic cytokines IL-1 alpha and IL-1 beta have been described. The IL-1 receptor Type I is an 80 kDa transmembrane protein that is expressed predominantly by T cells, fibroblasts, and endothelial cells. IL-1 receptor Type II is a 68 kDa transmembrane protein found on B lymphocytes, neutrophils, monocytes, large granular leukocytes and, endothelial cells. Both receptors are members of the immunoglobulin superfamily and show approximately 28% sequence similarity in their extracellular domains. The two receptor types do not heterodimerize in a receptor complex.

IL-1 RII has a short cytoplasmic domain and does not transduce IL-1 signals. In addition to the membrane-bound form of IL-1 RII, a naturally-occurring soluble form of IL-1 RII has been described. It has been suggested that the Type II receptor, either as the membrane-bound or as the soluble form, serves as a decoy for IL-1 and inhibits IL-1 action by blocking the binding of IL-1 to the signaling Type I receptor complex. Recombinant IL-1 soluble receptor type II is a potent antagonist of IL-1 action.

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.