HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Radcliffe, J. N. Articles by Thirdborough, S. M. Search for Related Content PubMed PubMed Citation Articles by Radcliffe, J. N. Articles by Thirdborough, S. M.

Prime-Boost with Alternating DNA Vaccines Designed to Engage Different Antigen Presentation Pathways Generates High Frequencies of Peptide-Specific CD8⁺ T Cells¹

Joanna N. Radcliffe^*, Joanne S. Roddick^*, Peter S. Friedmann, Freda K. Stevenson^* and Stephen M. Thirdborough^2,*

^* Cancer Sciences and Infection, Inflammation, and Repair Divisions, University of Southampton School of Medicine, Southampton General Hospital, Southampton, United Kingdom

The route for presentation of Ag to CD8⁺ or CD4⁺ T cells following DNA vaccination is critical for determining outcome, but the pathways involved are unclear. In this study, we compare two different DNA vaccine designs aimed to elicit CD8⁺ T cell responses against a specific peptide-epitope either by direct- or cross-presentation. Each carries sequences from tetanus toxin (TT) to provide essential CD4⁺ T cell help. In the first already proven design, the peptide-epitope is fused to the N-terminal domain of fragment C from TT. This appears to act mainly by cross-presentation. In the second design, the peptide-epitope is encoded by a minigene, with induction of Th responses mediated by coexpression of a hybrid invariant chain molecule, incorporating a single determinant from TT (p30) in exchange for class II-associated invariant chain peptide. This design appears to act mainly via direct presentation from transfected APCs. Both vaccines mediated Th-dependent priming of CD8⁺ T cells in mice, but the kinetics and level of the responses differed markedly, consistent with engagement of distinct pathways of Ag presentation. Importantly, the vaccines could be combined in an alternating prime-boost regime, in either order, generating substantially expanded memory CD8⁺ T cells, with potent effector function. Taken together, these results demonstrate that vaccination protocols involving different modes of Ag presentation at prime and boost can significantly improve the effectiveness of immunization.

The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

¹ This work was supported by the Leukaemia Research Fund United Kingdom.

² Address correspondence and reprint requests to Dr. Stephen M. Thirdborough, Somers Cancer Research Building, Mailpoint 824, Southampton General Hospital, Southampton SO16 6YD, U.K. E-mail address: S.M.Thirdborough{at}soton.ac.uk

³ Abbreviations used in this paper: DC, dendritic cell; N.FrC, N-terminal domain of tetanus toxin fragment C; THd, Th determinant; Ii, invariant chain; CLIP, class II-associated Ii peptide; ER, endoplasmic reticulum.

This article has been cited by other articles:

				A.-H. Hovav, M. W. Panas, C. E. Osuna, M. J. Cayabyab, P. Autissier, and N. L. Letvin The Impact of a Boosting Immunogen on the Differentiation of Secondary Memory CD8+ T Cells J. Virol., December 1, 2007; 81(23): 12793 - 12802. [Abstract] [Full Text] [PDF]