sh-Pentapeptide-16 SP is a single chain human peptide produced synthetically to be identical to a portion of the protein, Immunoglobulin Heavy Chain Junction Region, and contains 5 amino acids consisting of consisting of aspartic acid, phenylalanine, tryptophan and tyrosine. The parent protein contains a maximum of 18 amino acids which may contain disulfide bonds and/or glycosylation.