sh-Nonapeptide-10 SP is a single chain human peptide, produced synthetically to be identical to a portion of the protein, Complement C3, and contains 9 amino acids consisting of arginine, glutamic acid, glutamine, isoleucine, leucine, serine and threonine. Complement C3 contains a maximum of 1663 amino acids which may contain disulfide bonds and/or glycosylation. The protein consists of the proper sequence from the 20 standard amino acids.