Complement factor D, also known as adipsin, is a member of the chymotrypsin family of serine proteases, which plays an essential role in host defense as the rate-limiting enzyme in the alternative pathway of complement activation. Complement factor D activates a convertase (C3bBb) responsible for cleavage of the complement protein C3, which leads to the activation of terminal complement component C5-9 to form the membrane attack complex on microbial or cellular surfaces. It also functions in the regulation of systemic energy balance and physiologic and pathologic processes, including immunity and inflammation.
Lyophilized protein should be stored at -20˚C, though stable at room temperature for 3 weeks. Reconstituted protein solution can be stored at 4-7˚C for 2-7 days. Aliquots of reconstituted samples are stable at -20˚C for 3 months.