TNFRI belongs to the TNFR superfamily of transmembrane proteins, and is expressed in most cell types. Binding of either TNF-α or TNF-β to TNFRI initiates a signal transduction pathway that results in the activation of the transduction factor NF-κB, whose target genes are involved in the regulation of inflammatory responses, and, in certain cells induce apoptosis. Soluble TNF Receptor I (sTNFRI) is capable of inhibiting TNF-α and TNF-β activities by acting as a decoy receptor that serves as a sink for the TNF ligands. The human TNFRI gene encodes for a 455 amino acid type I transmembrane protein, which contains a 21 amino acid signal sequence, a 190 amino acid extracellular domain, a 23 amino acid transmembrane domain, and a 221 amino acid cytoplasmic domain. Recombinant Human sTNF Receptor Type I is an 18.3 kDa protein (162 amino acid residues) comprising the cysteine-rich, ligand-binding portion of the extracellular domain of the TNFRI protein.
Amino Acid Sequence
Determined by its inhibitory effect of the TNF-α mediated cytotoxicity in murine L-929 cells. The ED50 for this effect in the presence of 0.25 ng/ml of recombinant human TNF-α is 0.05 µg/ml.
Endotoxin level is <0.1 ng/μg of protein (<1EU/μg).
Centrifuge the vial prior to opening. Reconstitute in water to a concentration of 0.1–1.0 mg/ml. Do not vortex. For extended storage, it is recommended to further dilute in a buffer containing a carrier protein (example 0.1% BSA) and store in working aliquots at –20°C to –80°C.