Murine plasmacytoid dendritic cells induce effector/memory CD8+ T-cell responses in vivo after viral stimulation.

Unité de Biologie des Régulations Immunitaires, Institut National de la Santé et de la Recherche Médicale, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris cedex 15, France.
Blood (Impact Factor: 9.78). 10/2004; 104(6):1808-15. DOI: 10.1182/blood-2004-02-0426
Source: PubMed

ABSTRACT Like their human counterparts, mouse plasmacytoid dendritic cells (pDCs) play a central role in innate immunity against viral infections, but their capacity to prime T cells in vivo remains unknown. We show here that virus-activated pDCs differentiate into antigen-presenting cells able to induce effector/memory CD8(+) T-cell responses in vivo against both epitopic peptides and endogenous antigen, whereas pDCs activated by synthetic oligodeoxynucleotides containing unmethylated cytosine-guanine motifs (CpG) acquire only the ability to recall antigen-experienced T-cell responses. We also show that immature pDCs are unable to induce effector or regulatory CD8(+) T-cell responses. Thus, murine pDCs take part in both innate and adaptive immune responses by directly priming naive CD8(+) T cells during viral infection.

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