Plasmacytoid dendritic cells activate lymphoid-specific genetic programs irrespective of their cellular origin.

Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.
Immunity (Impact Factor: 19.8). 08/2004; 21(1):43-53. DOI: 10.1016/j.immuni.2004.06.011
Source: PubMed

ABSTRACT The developmental origin of type I interferon (IFN)-producing plasmacytoid dendritic cells (PDCs) is controversial. In particular, the rearrangement of immunoglobulin heavy chain (IgH) genes in murine PDCs and the expression of pre-T cell receptor alpha (pTalpha) gene by human PDCs were proposed as evidence for their "lymphoid" origin. Here we demonstrate that PDCs capable of IFN production develop efficiently from both myeloid- and lymphoid-committed progenitors. Rearranged IgH genes as well as RAG transcripts were found in both myeloid- and lymphoid-derived PDCs. The human pTalpha transgenic reporter was activated in both myeloid- and lymphoid-derived PDCs at a level comparable to pre-T cells. PDCs were the only cell population that activated murine RAG1 knockin and human pTalpha transgenic reporters outside the lymphoid lineage. These results highlight a unique developmental program of PDCs that distinguishes them from other cell types including conventional dendritic cells.

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