Mammalian milk osteopontin for enhancing immune responsiveness

The disclosed invention provides mammalian milk osteopontin and/or an active truncation or active peptide thereof for improving immune responsiveness to an infectious disease in a human subject, as well as enhancing the efficacy of vaccination for the prophylactic or therapeutic treatment of an infectious disease in humans. The invention further provides a vaccine system, for use in the prophylactic or therapeutic treatment of an infectious disease in a human, comprising a vaccine and a mammalian milk osteopontin and/or an active truncation or active peptide thereof for oral administration to a human, as well as methods of enhancing immune resistance to an infectious disease in a human by administration of a vaccine and a mammalian milk osteopontin and/or an active truncation thereof.