The Adjuvant Effect of Powdered Ferric Oxide: Enhancement of Response to Mycoplasma Pneumoniae and Respiratory Syncytial Virus Vaccines

Abstract

The ability of powdered magnetic oxide to adsorb respiratory syncytial virus and M. pneumoniae, and methods for simple elution of these agents have been described. When formaldehyde-inactivated vaccines incorporating iron oxide were tested in experimental animals, the metallic salt was found to act as an adjuvant and increased the antibody response. In a comparison with mineral oil-Arlacel adjuvant, it was found that the oil adjuvant was superior, but the Fe2O3 preparations were definitely superior to non-adjuvanted controls. Histologic examination of the site of inoculation revealed a mild, non-inflammatory response consisting of prolonged accumulation of tissue macrophages accompanied by slow dissolution and adsorption of the iron oxide. It is suggested that antigens adsorbed to iron oxide may be directed to various sites by the appropriate application of magnetic force.