Immunogenic properties of colloidal gold

We studied the capacity of colloidal gold for enhancing specific and nonspecific immune response in laboratory animals (rabbits, rats, and mice) immunized with antigens of various nature. The antibody titers obtained with colloidal gold as a carrier were higher as compared to the standard immunization techniques (free antigen or its combination with Freund's adjuvant). Application of colloidal gold also enhanced nonspecific immune responses, such as lysozyme concentration in the blood, activity of the complement system proteins, as well as phagocytic and bactericidal activities. The antibodies were tested by immunodot assay using gold markers. Immunization of the animals with colloidal gold conjugates with haptens or complete antigens (without other adjuvants) was shown to induce the production of highly active antibodies. In addition, the amount of antigen used for animal immunization with colloidal gold was an order of magnitude lower, compared to immunization with complete Freund's adjuvant. This fact can be evidence for adjuvant properties of colloidal gold proper.