Abstract |
A20 is a zinc finger protein with ubiquitin-modifying activity. A20 has been described as negatively regulating signaling induced by the TNF receptor and TLR family in a number of cell types, including mouse bone marrow-derived dendritic cells (DCs). However, the expression and effect of A20 in activated human monocyte-derived DCs have not been previously evaluated. We report that DCs activated with the TLR3 ligand poly(I:C) up-regulate A20. Down-regulating A20 demonstrated its role in the functional activation of DCs. A20 down-regulated DCs showed higher activation of the transcription factors NF-kappaB and activator protein-1, which resulted in increased and sustained production of IL-6, IL-10, and IL-12p70. We additionally silenced the immunosuppressive cytokine IL-10 and demonstrated that IL-10 inhibits T cell proliferation. We further demonstrated that A20 down-regulated DCs skew naive CD4+ T cells toward IFN-gamma producing Th1 cells, a process which is dependent on IL-12p70 and which is unaffected by IL-10. Furthermore, A20 and/or IL-10 down-regulated DCs had an enhanced capacity to prime Melan-A/MART-1 specific CD8+ T cells. Finally, we demonstrated that potent T cell stimulatory DCs are generated by the simultaneous delivery of poly(I:C12U), A20, or A20/IL-10 small interfering RNA and Ag-encoding mRNA, introducing a one step approach to improve DC-based vaccines. Together these findings demonstrate that A20 negatively regulates NF-kappaB and activator protein-1 in DCs and that down-regulation of A20 results in DCs with enhanced T cell stimulatory capacity.
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Authors | Karine Breckpot, Cindy Aerts-Toegaert, Carlo Heirman, Uschi Peeters, Rudi Beyaert, Joeri L Aerts, Kris Thielemans |
Journal | Journal of immunology (Baltimore, Md. : 1950)
(J Immunol)
Vol. 182
Issue 2
Pg. 860-70
(Jan 15 2009)
ISSN: 1550-6606 [Electronic] United States |
PMID | 19124729
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Adjuvants, Immunologic
- Cancer Vaccines
- DNA-Binding Proteins
- Interleukin-6
- Intracellular Signaling Peptides and Proteins
- NF-kappa B
- Nuclear Proteins
- RNA, Double-Stranded
- RNA, Small Interfering
- Transcription Factor AP-1
- Interleukin-10
- Interleukin-12
- TNFAIP3 protein, human
- Tumor Necrosis Factor alpha-Induced Protein 3
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Topics |
- Adjuvants, Immunologic
(biosynthesis, genetics, physiology)
- CD4-Positive T-Lymphocytes
(immunology)
- Cancer Vaccines
(genetics, immunology)
- Cells, Cultured
- Coculture Techniques
- DNA-Binding Proteins
- Dendritic Cells
(immunology, metabolism, transplantation)
- Down-Regulation
(genetics, immunology)
- Humans
- Interleukin-10
(biosynthesis)
- Interleukin-12
(biosynthesis)
- Interleukin-6
(biosynthesis)
- Intracellular Signaling Peptides and Proteins
(antagonists & inhibitors, genetics)
- Lymphocyte Activation
(genetics, immunology)
- Monocytes
(immunology, metabolism)
- NF-kappa B
(antagonists & inhibitors, biosynthesis)
- Nuclear Proteins
(antagonists & inhibitors, biosynthesis, genetics)
- RNA Interference
(immunology)
- RNA, Double-Stranded
(physiology)
- RNA, Small Interfering
(physiology)
- Transcription Factor AP-1
(antagonists & inhibitors, biosynthesis)
- Tumor Necrosis Factor alpha-Induced Protein 3
- Up-Regulation
(genetics, immunology)
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