Structural and Immunochemical Studies on Bovine Lactoferrin Fragments

Abstract

Lactoferrin (Lt) is a metal-binding protein found in milk and other secretory fluids and also in blood. It shows multifunctional properties but the mechanism of developing its function in living systems has not been resolved yet. It is known to exert bacteriostatic effects due to its ability to bind environmental iron. Moreover, apo-lactoferrin has been shown to bind to microbial membranes and causes the direct destruction of microorganisms. Other biological functions attributed to lactoferrin include roles in modulation of the inflammatory response, activation of the immune system, and control of myelopoiesis or cell growth. This molecule is constructed with N- and C-lobes, each of which is composed of 3 domains¹. The function of each lobe has been studying and there are certain differences. The biologically significant function has been found mainly in N-lobe. For the aids of resolving their functional analysis, the authors prepared the monoclonal antibodies (mAb) against N-lobe and C-lobe of bovine lactoferrin. To prepare the mAb specific to N-lobe, we used lactoferricin^® B (bLfcin, an anti-microbial peptide isolated from N-lobe²) as an antigen³. In this paper, the characterization of the mAb against lactoferrin fragments has been examined and the structure of the mAb-recognition site on lactoferrin molecule was identified.