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bioRxiv · 10.1101/310680

Lymphoid origin of a lineage of intrinsically activated plasmacytoid dendritic cell in mice and humans

Dekker, J. D.·Rhee, C.·Hu, Z.·Lee, B.-K.·Lee, J.·Iyer, V. R.·Ehrlich, L. I. R.·Georgiou, G.·Tucker, H. O.·Ippolito, G. C.
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Abstract

We identified a novel mouse plasmacytoid dendritic cell (pDC) lineage derived from the common lymphoid progenitors (CLPs) that is dependent on expression of Bcl11a. These CLP-derived pDCs, which we refer to as "B-pDCs", have a unique gene expression profile that includes hallmark B cell genes, normally not expressed in conventional pDCs. Despite expressing most classical pDC markers such as SIGLEC-H and PDCA1, B-pDCs lack IFN- secretion, exhibiting a distinct inflammatory profile. Functionally, B-pDCs induce T cell proliferation more robustly than canonical pDCs following Toll-like receptor 9 (TLR9) engagement. B-pDCs, along with another homogeneous subpopulation of myeloid derived pDCs, display elevated levels of the cell-surface receptor tyrosine kinase AXL, mirroring human AXL+ transitional DCs in function and transcriptional profile. Murine B-pDCs therefore represent a phenotypically and functionally distinct CLP-derived DC lineage specialized in T cell activation and previously not described in mice.

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Dekker, J. D., Rhee, C., Hu, Z., Lee, B.-K., Lee, J., Iyer, V. R., Ehrlich, L. I. R., Georgiou, G., Tucker, H. O., Ippolito, G. C.. 2018-04-28. Lymphoid origin of a lineage of intrinsically activated plasmacytoid dendritic cell in mice and humans. https://doi.org/10.1101/310680

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