Purity: > 90% by SDS - PAGE Format: Liquid. In Phosphate Buffered Saline (pH 7.4) containing 10% glycerol.. SERPING1, also known as plasma protease C1 inhibitor, is a protease inhibitor belonging to the serpin superfamily. This protein is the physiological inhibitor of activated C1r and C1s, two serine proteases involved in the classical complement pathway. Also, it has a 2-domain structure, unlike most family members. The C-terminal serpin domain is similar to other serpins, and this part of this inhibitor provides the inhibitory activity. C1-inhibitor is highly glycosylated, bearing both N- and O-glycans. Deficiency of this protein results in hereditary angioedema, which is characterized by recurrent episodes of localized angioedema of the skin, gastrointestinal mucosa or upper respiratory mucosa. It is an attractive therapeutic protein to treat inflammatory diseases other than HAE. Recombinant human SERPING1, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.