Publication

MHC Class II-restricted antigen presentation by plasmacytoid dendritic cells drives proatherogenic T cell immunity

Journal Paper/Review - Sep 15, 2014

Units
PubMed
Doi

Citation
Sage A, Hugues S, Reizis B, Hansson G, Reith W, Ludewig B, Harrison J, Grassia G, Ait-Oufella H, Finigan A, Cambrook H, Baker L, Sabir S, Masters L, Maffia P, Murphy D, Mallat Z. MHC Class II-restricted antigen presentation by plasmacytoid dendritic cells drives proatherogenic T cell immunity. Circulation 2014; 130:1363-73.
Type
Journal Paper/Review (English)
Journal
Circulation 2014; 130
Publication Date
Sep 15, 2014
Issn Electronic
1524-4539
Pages
1363-73
Brief description/objective

BACKGROUND
Plasmacytoid dendritic cells (pDCs) bridge innate and adaptive immune responses and are important regulators of immuno-inflammatory diseases. However, their role in atherosclerosis remains elusive.

METHODS AND RESULTS
Here, we used genetic approaches to investigate the role of pDCs in atherosclerosis. Selective pDC deficiency in vivo was achieved using CD11c-Cre × Tcf4(-/flox) bone marrow transplanted into Ldlr(-/-) mice. Compared with control Ldlr(-/-) chimeric mice, CD11c-Cre × Tcf4(-/flox) mice had reduced atherosclerosis levels. To begin to understand the mechanisms by which pDCs regulate atherosclerosis, we studied chimeric Ldlr(-/-) mice with selective MHCII deficiency on pDCs. Significantly, these mice also developed reduced atherosclerosis compared with controls without reductions in pDC numbers or changes in conventional DCs. MHCII-deficient pDCs showed defective stimulation of apolipoprotein B100-specific CD4(+) T cells in response to native low-density lipoprotein, whereas production of interferon-α was not affected. Finally, the atheroprotective effect of selective MHCII deficiency in pDCs was associated with significant reductions of proatherogenic T cell-derived interferon-γ and lesional T cell infiltration, and was abrogated in CD4(+) T cell-depleted animals.

CONCLUSIONS
This study supports a proatherogenic role for pDCs in murine atherosclerosis and identifies a critical role for MHCII-restricted antigen presentation by pDCs in driving proatherogenic T cell immunity.