Aluminium compounds for use in vaccines
Aluminium adjuvants are the most widely used adjuvants in both human and veterinary vaccines. These adjuvants have been used in practical vaccination for more than 60 years and are generally recognized as safe and as stimulators of Th2 immunity. The present review gives a short introduction to the pioneering research at the start of the use of aluminium compounds as adjuvants, including references on the chemistry of these compounds. Analytical methods for identifying the most commonly used aluminium compounds, such as boehmite and aluminium hydroxyphosphate, are mentioned. Emphasis is placed on the important factors for antigen adsorption and on the latest work using gene-deficient mice in the research of the mechanism of aluminium adjuvants in terms of cytokine and T-cell subset stimulation. Key references on the ability of aluminium adjuvants to stimulate IgE and also in vivo clearing of aluminium adjuvants are discussed. Furthermore, the review addresses the issue of local reactions in the context of injection route and local tissue disturbance. Possible new applications of aluminium adjuvants in, for example, combined aluminium-adsorbed protein and DNA oligonucleotide vaccines as well as the possible use of aluminium adjuvants in combination with IL-12 to stimulate Th1-type immune responses are mentioned.