Anti-peregrin antibodies enable researchers to detect and measure the peregrin antigen in biological samples. This target is a reported synonym of the BRPF1 gene, which encodes bromodomain and PHD finger containing 1. This protein is known to function in chromatin remodeling and the regulation of transcription, among other biological roles. The human version of peregrin has a canonical amino acid length of 1214 residues and a protein mass of 137.5 kilodaltons, although 4 isoforms have been identified. It is reported to be localized in the nucleus and cytoplasm of cells and widely expressed in many tissue types. Other names for this target antigen include BR140 and IDDDFP.