Related Experiment Video
Updated: Apr 17, 2026
Subcutaneous Angiotensin II Infusion using Osmotic Pumps Induces Aortic Aneurysms in Mice
Published on: September 28, 2015
ApoB-100-related peptide vaccine protects against angiotensin II-induced aortic aneurysm formation and rupture
Tomoyuki Honjo1, Kuang-Yuh Chyu1, Paul C Dimayuga1
1Oppenheimer Atherosclerosis Research Center, Division of Cardiology, Cedars-Sinai Heart Institute, Los Angeles, California.
Background:
T cells and macrophages are implicated in the pathogenesis of aortic aneurysm (AA) and atherosclerosis. We recently demonstrated that a vaccine using an apoB-100-related peptide p210 reduces atherosclerosis with favorable modulation of CD8+ T cells in apolipoprotein E-deficient (apoE-/-) mice.
Objectives:
This study hypothesized that a p210 vaccine could reduce AA formation in the angiotensin II (Ang II)-induced AA model.
Methods:
Male apoE-/- mice were immunized with p210 vaccine and implanted with an Ang II-releasing pump for 4 weeks. Flow cytometry assessed T cell activation and phenotype. Interleukin-6 (IL-6) and monocyte chemotactic protein 1 (MCP-1) expression were assessed using reverse transcription polymerase chain reaction. We used ex vivo aortic explants to test monocyte adhesion and in vitro cocultures to evaluate CD8+ T cell function.
Results:
The p210 vaccine activated CD8+ T cells and reduced AA formation and mortality due to AA rupture, which was attenuated by CD8+ T cell depletion. Vaccination decreased expression of IL-6 and MCP-1 and reduced macrophage infiltration in the aorta. Cytotoxic T-lymphocyte assay showed that CD8+ T cells from p210-immunized mice had higher lytic activity against Ang II-stimulated macrophages. The p210 vaccine decreased splenic Th17 cells, and in vitro coculture of CD4+ and CD8+ T cells showed that CD8+ T cells from p210-immunized mice inhibited the polarization of CD4+ T cells into Th17 cells. IL-17A-/- mice infused with a higher dose of Ang II did not develop AA rupture.
Conclusions:
A p210 vaccine protected against Ang II-induced AA formation and mortality by reducing macrophage infiltration in the aorta and decreasing Th17 cell polarization. Our findings provide a potentially novel immunomodulating approach against AA.
