An oil-in-water adjuvant appears to make the swine- and avian-flu vaccines more effective in humans, reports a new study. Oil-in-water adjuvants are literally a mix of oil and water. Immunologists think that the emulsion attracts competent immune cells to the site of injection and creates a local environment that facilitates the immune response so that the antigen works better.
Hana Golding, Surrender Khorana, and colleagues conducted studies on the effectiveness of oil-in-water adjuvant when combined with pandemic influenza vaccines. They measured the strength of human antibodies against the flu vaccine in the presence of MF59, looking at cohorts of different age groups (toddlers, children, and adults) vaccinated with the swine origin-H1N1 vaccine, and in a separate study, adults vaccinated with avian-H5N1 vaccine. In both studies, subjects received either unadjuvanted or MF59 -adjuvanted inactivated subunit vaccines. The researchers showed that the adjuvant increased the magnitude, diversity, and most importantly, the binding avidity of the antibodies, potentially a crucial factor when antibodies in limiting quantities encounter virus. Specifically, antibodies—with the help of the MF59 adjuvant—are able to latch strongly onto receptor binding domains on the virus key surface protein (hemagglutinin) and prevent infection. These findings demonstrated for the first time that oil-in-water adjuvants can improve antibody quality in a manner that is predicted to improve protection against pathogenic influenza strains.
Adjuvants may allow vaccine manufacturers to boost recipient’s immune response while using lower doses of antigen, which are usually expensive and in limited supply.
"MF Adjuvant Enhances Diversity and Affinity of Antibody-Mediated Immune Response to Pandemic Influenza Vaccines."
Science Translational Medicine
3, 85ra48 (2011)
Surender Khurana,1 Nitin Verma,1 Jonathan W. Yewdell,2 Anne Katrin Hilbert,3 Flora Castellino,4 Maria Lattanzi,44 Giuseppe Del Giudice,4 Rino Rappuoli,4 Hana Golding1
1Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892, USA. 2Laboratory of Viral Diseases, National Institutes of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD 20892, USA, 3Novartis Vaccines and Diagnostics GmbH, Marburg 35041, Germany, 4Novartis Vaccines and Diagnostics Research Center, Siena 53100, Italy