Vaccination against T-cell epitopes of native ApoB100 reduces vascular inflammation and disease in a humanized mouse model of atherosclerosis
- Autores: A. Gisterå, A. Hermansson, D. Strodthoff, M. L. Klement, U. Hedin, G.N. Fredrikson, J. Nilsson, Göran K. Hansson , D. F. J. Ketelhuth
- Localización: Journal of Internal Medicine, ISSN-e 1365-2796, Vol. 281, Nº. 4, 2017, págs. 383-397
- Idioma: inglés
- Texto completo no disponible (Saber más ...)
-
Resumen
Background and Objectives The T-cell response to low-density lipoprotein (LDL) in the vessel wall plays a critical role in atherosclerotic plaque formation and stability. In this study, we used a new translational approach to investigate epitopes from human apolipoprotein B100 (ApoB100), the protein component of LDL, which triggers T-cell activation. We also evaluated the potential of two selected native ApoB100 epitopes to modulate atherosclerosis in human ApoB100-transgenic Ldlr−/− (HuBL) mice.
Methods and Results HuBL mice were immunized with human atherosclerotic plaque homogenate to boost cellular autoimmune response to tissue-derived ApoB100 epitopes. In vitro challenge of splenocytes from immunized mice with a library of overlapping native peptides covering human ApoB100 revealed several sequences eliciting T-cell proliferation. Of these sequences, peptide (P) 265 and P295 were predicted to bind several human leucocyte antigen (HLA) haplotypes and induced high levels of interferon (IFN)-γ. Vaccination of HuBL mice with these peptides mounted a strong adaptive immune response to native ApoB100, including high levels of epitope-specific plasma IgGs. Interestingly, P265 and P295 vaccines significantly decreased plaque size, reduced macrophage infiltration and increased IgG1 deposition in the plaques. Purified IgGs from vaccinated mice displayed anti-inflammatory properties against macrophages in vitro, reducing their response to LPS in a dose-dependent manner.
Conclusion We identified two specific epitopes from human native ApoB100 that trigger T-cell activation and protect HuBL mice against atherosclerosis when used in a vaccine. Our data suggest that vaccination-induced protective mechanisms may be mediated at least in part through specific antibody responses to LDL that inhibit macrophage activation.
