title: Transport of iron bound to recombinant human lactoferrin from rice and iron citrate across Caco-2 cell monolayers.
abstract: The possibility of using recombinant human lactoferrin from rice (rhLF) makes it necessary to study its differences from the protein of milk. In this work, the binding of different iron-saturated forms of rhLF to Caco-2 cells was studied. Iron-saturated rhLF bound in higher proportion than the apo-form, but, the data obtained for specific binding were not compatible with receptor-mediated binding. Competition assays showed the same binding capacity for human milk lactoferrin as for rhLF to Caco-2 cells. Another basic protein of milk, lactoperoxidase, was found to compete with rhLF for binding to Caco-2 cell membranes, suggesting an electrostatic interaction. The transport of iron ((59)Fe) bound to rhLF and to citrate and the transport of rhLF ((125)I-labeled) were studied on Caco-2 monolayers. Transport of iron was found to be significantly greater when bound to citrate than to rhLF. The amount of intact lactoferrin that traversed the Caco-2 monolayers was very low, suggesting degradation of it across these cells.
authors: Department of Animal Production and Food Science, Food Technology Unit, Veterinary Faculty, University of Zaragoza, Spain.
authors: Celia
authors: C
authors: Conesa
authors: Coloma
authors: C
authors: Pocoví
authors: María-Dolores
authors: MD
authors: Pérez
authors: Miguel
authors: M
authors: Calvo
authors: Lourdes
authors: L
authors: Sánchez
mesh_terms: D000818:Animals; D001692:Biological Transport; D018938:Caco-2 Cells; D002417:Cattle; D002462:Cell Membrane / Q000378:metabolism; D005290:Ferric Compounds / Q000378:metabolism*; D006801:Humans; D007501:Iron / Q000378:metabolism*; D007781:Lactoferrin / Q000378:metabolism*; D012275:Oryza; D010940:Plant Proteins / Q000378:metabolism*; D011485:Protein Binding; D011994:Recombinant Proteins / Q000378:metabolism*
chemical_list: D005290:Ferric Compounds; D010940:Plant Proteins; D011994:Recombinant Proteins; C025314:ferric citrate; D007501:Iron; D007781:Lactoferrin