Cyclophilin B

Patent Granted Cyclophilins are a family of proteins from vertebrates and other organisms that bind to cyclosporine, an immunosuppressant which is usually used to suppress rejection after internal organ transplants.[1] These proteins have peptidyl prolyl isomerase activity, which catalyzes the isomerization of peptide bonds from trans form to cis form at proline residues and facilitates protein folding. Cyclophilin A is a cytosolic and highly abundant protein. The protein belongs to a family of isozymes, including cyclophilins B and C, and natural killer cell cyclophilin-related protein.[2][3][4] Major isoforms have been found throughout the cell, including the ER, and some are even secreted.