April 1998 Volume 4 Number 4 p397
Enhanced immunogenicity for CD8+ T cell induction and complete protective efficacy of malaria DNA vaccination by boosting with modified vaccinia virus Ankara
Jörg Schneider1, Sarah C. Gilbert2, Tom J. Blanchard3, Tomas Hanke1, Kathryn J. Robson4, Carolyn M. Hannan1, Marion Becker3, Robert Sinden5, Geoffrey L. Smith3 & Adrian V.S. Hill1,2
Immunization with irradiated sporozoites can protect against malaria infection and intensive efforts are aimed at reproducing this effect with subunit vaccines. A particular sequence of subunit immunization with pre-erythrocytic antigens of Plasmodium berghei, consisting of single dose priming with plasmid DNA followed by a single boost with a recombinant modified vaccinia virus Ankara (MVA) expressing the same antigen, induced unprecedented complete protection against P. berghei sporozoite challenge in two strains of mice. Protection was associated with very high levels of splenic peptide-specific interferon-gamma-secreting CD8+ T cells and was abrogated when the order of immunization was reversed. DNA priming followed by MVA boosting may provide a general immunization regime for induction of high levels of CD8+ T cells.
1Molecular Immunology Group, Institute of Molecular Medicine, Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK.2Wellcome Trust Centre for Human Genetics, University of Oxford, Windmill Road, Headington, Oxford OX3 7BN, UK.3Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK.4MRC Molecular Haematology Unit, Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK.5Molecular and Cellular Parasitology Group, Department of Pure and Applied Biology, Imperial College, London, UK.Correspondence should be addressed to J.S.; e-mail: email@example.com