Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

In the search for effective vaccines against intracellular pathogens such as HIV, tuberculosis and malaria, recombinant viral vectors are increasingly being used to boost previously primed T cell responses. Published data have shown prime-boost vaccination with BCG-MVA85A (modified vaccinia virus Ankara expressing antigen 85A) to be highly immunogenic in humans as measured by ex vivo IFN-gamma ELISPOT. Here, we used polychromatic flow cytometry to investigate the phenotypic and functional profile of these vaccine-induced Mycobacterium tuberculosis (M.tb) antigen 85A-specific responses in greater detail. Promisingly, antigen 85A-specific CD4(+) T cells were found to be highly polyfunctional, producing IFN-gamma, TNF-alpha, IL-2 and MIP-1beta. Surface staining showed the responding CD4(+) T cells to be relatively immature (CD45RO(+) CD27(int)CD57(-)); this observation was supported by the robust proliferative responses observed following antigenic stimulation. Furthermore, these phenotypic and functional properties were independent of clonotypic composition and epitope specificity, which was maintained through the different phases of the vaccine-induced immune response. Overall, these data strongly support the use of MVA85A in humans as a boosting agent to expand polyfunctional M.tb-specific CD4(+) T cells capable of significant secondary responses.

Original publication

DOI

10.1002/eji.200737504

Type

Journal article

Journal

Eur J Immunol

Publication Date

11/2007

Volume

37

Pages

3089 - 3100

Keywords

Acyltransferases, Adolescent, Adult, Amino Acid Sequence, Antigens, Bacterial, BCG Vaccine, CD4-Positive T-Lymphocytes, Flow Cytometry, Gene Expression, Genes, T-Cell Receptor beta, Genetic Vectors, Humans, Immunologic Memory, Middle Aged, Molecular Sequence Data, Mycobacterium bovis, Mycobacterium tuberculosis, Phenotype, T-Lymphocyte Subsets, Tuberculosis, Vaccinia virus