Anti-OTK4 antibodies are protein reagents that detect specific antigens. The OTK4 antigen is another term for the human protein FKBP prolyl isomerase 1B, encoded by the FKBP1B gene. The protein is known to have the potential to contribute to the immunosuppressive and toxic effects of FK506 and rapamycin. Canonically, it has an amino acid length of 108 residues and a mass of 11.8 kilodaltons. Its subcellular localization is in the cytoplasm and it is notably expressed in the heart muscle. The OTK4 protein is a member of the FKBP-type PPIase protein family. Other alias names for OTK4 include FKBP12.6 and FKBP1L. Indicated applications for OTK4 antibodies listed below include ELISA, Western Blot, Immunofluorescence, and Immunohistochemistry.