Monoclonal antibody a-bC-lobe, anti bovine Lactoferrin (Lf) is highly specific for bovine Lactoferrin. This protein is a member of the transferrin family of metal-binding proteins found in milk and other secretory fluids and also in blood. It shows multifunctional properties of which the bacteriostatic and bactericidal effects are the best known. The molecule is constructed with a N-terminal half molecule (N-lobe) and a C-terminal half molecule (C-lobe), each of which is composed of two domains. The biologically important functions have been found mainly in the N-lobe. The lactoferrin determinants responsible for binding to Ca2+-dependent receptor on hepatocytes are present within the C-lobe. The monoclonal antibody a-bC-lobe shows strong reactivities with both native and denatured forms of bovine lactoferrin and C-lobe. The "WNIPMGL" sequence (467-473 of bovine lactoferrin) is the antigenic determinant or epitopic site of the anti C-lobe antibody a-bC-lobe.The antibody shows weak reactivity with human lactoferrin and korean goat lactoferrin, slight cross reactivity is seen with bovine transferrin, whereas no cross reactivity is seen with human transferrin and chicken ovotransferrin.