Western Blot: Complement C3a Antibody (2B5) [NBP3-17997] - Western blot analysis of Complement C3a antibody (2B5) on human serum samples. 0.1ug human C3 protein (lane 1), 10ug normal human serum proteins (lane 2) was blotted with Complement C3a antibody (2B5) at a concentration 1:3000. The Complement C3a antibody (2B5) binds strongly and cleanly to a band at about 115 kDa which represents the intact alpha subunit of C3 and a weaker proteolytic band at approximately 45kDa which is the C-terminal of the alpha subunit including the netrin domain. Bands at 190kDa and above are likely the pro-C3 and its glycosylated form.