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Organ-dependent in vivo priming of naive CD4+, but not CD8+, T cells by plasmacytoid dendritic cells.

ABSTRACT: Plasmacytoid dendritic cells (PDCs) play a pivotal role as cytokine-secreting accessory cells in the antimicrobial immune defense. In contrast, the capacity of PDCs to act as antigen-presenting cells in naive T cell priming remains unclear. By studying T cell responses in mice that lack conventional DCs (cDCs), and by the use of a PDC-specific antigen-targeting strategy, we show that PDCs can initiate productive naive CD4(+) T cell responses in lymph nodes, but not in the spleen. PDC-triggered CD4(+) T cell responses differed from cDC-driven responses in that they were not associated with concomitant CD8(+) T cell priming. Our results establish PDCs as a bona fide DC subset that initiates unique CD4(+) Th cell-dominated primary immune responses.

SUBMITTER: Sapoznikov A

PROVIDER: S-EPMC2118686 | biostudies-literature | 2007 Aug

REPOSITORIES: biostudies-literature

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Organ-dependent in vivo priming of naive CD4+, but not CD8+, T cells by plasmacytoid dendritic cells.

Sapoznikov Anita A Fischer Jens A A JA Zaft Tami T Krauthgamer Rita R Dzionek Andrzej A Jung Steffen S

The Journal of experimental medicine 20070723 8

Plasmacytoid dendritic cells (PDCs) play a pivotal role as cytokine-secreting accessory cells in the antimicrobial immune defense. In contrast, the capacity of PDCs to act as antigen-presenting cells in naive T cell priming remains unclear. By studying T cell responses in mice that lack conventional DCs (cDCs), and by the use of a PDC-specific antigen-targeting strategy, we show that PDCs can initiate productive naive CD4(+) T cell responses in lymph nodes, but not in the spleen. PDC-triggered C ...[more]

PMID: 17646404

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