Merck, SAE0198-50UG, Calprotectin, human recombinant

General description
This recombinant human calprotectin is a heterodimer composed of tagged versions of both S100A8 and S100A9, where a 6xHis Sumo tag is added to the N-terminus of S100A8 and, a 6XHis tag is added to the N-terminus of S100A9. This tagged version was found to have enhanced stability as compared to untagged versions of this protein. Removal of the tags can be achieved using HRV-3C protease (SAE0045 or SAE0110).
Application
Fecal Calprotectin is often used as a biomarker to identify inflammation in gastrointestinal disease¹. This product is a recombinant version of the human protein found endogenously.
Biochem/physiol Actions
Calprotectin is a calcium and zinc binding protein that belongs to the S100 family. It is a heterodimer protein composed of S100A8 and S100A9.¹ The protein is expressed in myeloid cells and in circulating monocytes and neutrophils, where it accounts for 60% of the cytosolic protein content. Calprotectin was found to play major roles in inflammation and the immune response by activation of NF-kB pathway via TLR4 and AGER,² and its antimicrobial activity possibly through chelating of Zn.³ High concentrations of calprotectin are found and serve as a biomarker in rheumatoid, cystic fibrosis, inflammatory bowel disease and in Crohn′s disease.⁴ A meta-analysis also identified calprotectin as a potential biomarker for COVID-19.⁵
Physical form
The product is lyophilized from a sterile 0.2 µm filtered solution containing 12.5 mM Tris-Cl (pH 8.0), 150 mM NaCl, and 1 mM DTT.
Preparation Note
Reconstitute lyophilized vial in DMEM or in PBS to a concentration up to 500 µg/mL. Spin down to collect material. Reconstituted product should be stored in working aliquots at –20 °C. Do not store in a frost-free freezer. Avoid freeze-thaw cycles.