Antigen depot is not required for alum adjuvanticity

• Published in: The FASEB journal Vol. 26; no. 3; pp. 1272 - 1279
• Main Authors: Hutchison, Sharon, Benson, Robert A., Gibson, Vivienne B., Pollock, Abigail H., Garside, Paul, Brewer, James M.
• Format: Journal Article
• Language: English
• Published: Bethesda, MD, USA Federation of American Societies for Experimental Biology 01.03.2012
• Subjects: Adjuvants, Immunologic - pharmacology; Alum Compounds - pharmacology; Animals; Antigen Presentation - drug effects; Antigen Presentation - immunology; Antigen-Presenting Cells - drug effects; Antigen-Presenting Cells - immunology; Antigen-Presenting Cells - metabolism; Antigens - administration & dosage; Antigens - immunology; Antigens - metabolism; B-Lymphocytes - drug effects; B-Lymphocytes - immunology; B-Lymphocytes - metabolism; Dendritic Cells - drug effects; Dendritic Cells - immunology; Dendritic Cells - metabolism; Female; Flow Cytometry; in vivo; Lymph Nodes - drug effects; Lymph Nodes - immunology; Lymph Nodes - metabolism; Lymphocyte Activation - drug effects; Lymphocyte Activation - immunology; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Transgenic; Oligodeoxyribonucleotides - pharmacology; Ovalbumin - administration & dosage; Ovalbumin - immunology; Ovalbumin - pharmacokinetics; T-Lymphocytes - drug effects; T-Lymphocytes - immunology; T-Lymphocytes - metabolism; Time Factors; vaccine
• ISSN: 0892-6638; 1530-6860
• DOI: 10.1096/fj.11-184556

Alum adjuvants have been in continuous clinical use for more than 80 yr. While the prevailing theory has been that depot formation and the associated slow release of antigen and/or inflammation are responsible for alum enhancement of antigen presentation and subsequent T‐ and B‐cell responses, this has never been formally proven. To examine antigen persistence, we used the chimeric fluorescent protein EαGFP, which allows assessment of antigen presentation in situ, using the Y‐Ae antibody. We demonstrate that alum and/or CpG adjuvants induced similar uptake of antigen, and in all cases, GFP signal did not persist beyond 24 h in draining lymph node antigen‐presenting cells. Antigen presentation was first detectable on B cells within 6‐12 h of antigen administration, followed by conventional dendritic cells (DCs) at 12‐24 h, then finally plasmacytoid DCs at 48 h or later. Again, alum and/or CpG adjuvants did not have an effect on the magnitude or sequence of this response; furthermore, they induced similar antigen‐specific T‐cell activation in vivo. Notably, removal of the injection site and associated alum depot, as early as 2 h after administration, had no appreciable effect on antigen‐specific T‐and B‐cell responses. This study clearly rules out a role for depot formation in alum adjuvant activity.—Hutchison, S., Benson, R. A., Gibson, V. B., Pollock, A. H., Garside, P., Brewer, J. M. Antigen depot is not required for alum adjuvanticity. FASEB J. 26, 1272‐1279 (2012). www.fasebj.org