CD8+ T-cells can differentiate into subpopulations that are characterized by a specific cytokine profile, such as the Tc17 population that produces IL-17. The role of this CD8+ T-cell subset in... Show moreCD8+ T-cells can differentiate into subpopulations that are characterized by a specific cytokine profile, such as the Tc17 population that produces IL-17. The role of this CD8+ T-cell subset in atherosclerosis remains elusive. In this study, we therefore investigated the contribution of Tc17 cells to the development of atherosclerosis.\nFlow cytometry analysis of atherosclerotic lesions from apoE-/- mice revealed a pronounced increase in RORγt+CD8+ T-cells compared to the spleen, indicating a lesion-specific increase in Tc17 cells. To study whether and how the Tc17 subset affects atherosclerosis, we performed an adoptive transfer of Tc17 cells or undifferentiated Tc0 cells into CD8-/-LDLr-/- mice fed a Western-type diet. Using flow cytometry, we showed that Tc17 cells retained a high level of IL-17A production in vivo. Moreover, Tc17 cells produced lower levels of IFN-γ than their Tc0 counterparts. Analysis of the aortic root revealed that the transfer of Tc17 cells did not increase atherosclerotic lesion size, in contrast to Tc0-treated mice.\nThese findings demonstrate a lesion-localized increase in Tc17 cells in an atherosclerotic mouse model. Tc17 cells appeared to be non-atherogenic, in contrast to their Tc0 counterpart.\nCD8+ T-cells are present in high numbers in human atherosclerotic plaques, however their role in inflammation and the pathogenesis of atherosclerosis remains elusive. Our results indicate that the majority of CD8+ T-cells in atherosclerotic plaques of mice have lost their ability to produce the pro-inflammatory cytokine IFN-γ and gain traits of IL-17-producing CD8+ T-cells (Tc17 cells). We show that this subset of CD8+ T-cells is less atherogenic then IFN-γ producing Tc1 cells. Show less
Benne, N.; Duijn, J. van; Lozano Vigario, F.L.; Leboux, R.J.T.; Veelen, P. van; Kuiper, J.; ... ; Slütter, B. 2018
Atherosclerosis is the predominant underlying pathology of many types of cardiovascular disease and is one of the leading causes of death worldwide. It is characterized by the retention of oxidized... Show moreAtherosclerosis is the predominant underlying pathology of many types of cardiovascular disease and is one of the leading causes of death worldwide. It is characterized by the retention of oxidized low-density lipoprotein (ox-LDL) in lipid-rich macrophages (foam cells) in the intima of arteries. Autoantigens derived from oxLDL can be used to vaccinate against atherosclerosis. However, a major challenge is the induction of antigen-specific Tregs in a safe and effective way. Here we report that liposomes containing the anionic phospholipid 1,2distearoyl-sn-glycero-3-phosphoglycerol (DSPG) induce Tregs that are specific for the liposomes' cargo. Mechanistically, we show a crucial role for the protein corona that forms on the liposomes in the circulation, as uptake of DSPG-liposomes by antigen-presenting cells is mediated via complement component lq (Clq) and scavenger receptors (SRs). Vaccination of atherosclerotic mice on a western-type diet with DSPG-liposomes encapsulating an LDL-derived peptide antigen significantly reduced plaque formation by 50% and stabilized the plaques, and reduced serum cholesterol concentrations. These results indicate that DSPG-liposomes have potential as a delivery system in vaccination against atherosclerosis. Show less
Benne, N.; Duijn, J. van; Vigario, F.L.; Leboux, R.J.T.; Veelen, P. van; Kuiper, J.; ... ; Stutter, B. 2018
