Influenza vaccination promotes stable atherosclerotic plaques in apoE knockout mice

Effect of Influenza Vaccination on Risk of Stroke: A Systematic Review and Meta-Analysis

“…The influenza-induced systemic inflammatory response precipitates vulnerable plaque rupture via altered concentrations of reactant proteins and cytokines, accelerates endothelial injury by impairing vasodilatation via metabolic derangements, and enhances thrombotic tendencies through altered clotting factors and platelet dysfunction [33]. In a study with apoE knockout mice, influenza vaccination resulted in atherosclerotic regions with lower lipid content and higher concentrations of smooth muscle cells and collagen [9]. …”

“…Of late, there is growing interest in the use of influenza vaccines for preventing CVD, primarily coronary artery disease In mouse models, influenza vaccination protects against acute myocardial infarction, with reduced atherosclerotic plaque size, increased plaque stability, and decreased pro-inflammatory markers [9]. An increasing body of evidence suggests that influenza vaccines protect against heart disease in terms of both primary prevention and secondary prevention [6,10].…”

Mechanistic links between acute respiratory tract infections and acute coronary syndromes

“…In a recent study, ApoE À/À mice receiving influenza vaccination had smaller atherosclerotic plaques compared to controls. 140 Plaques in vaccinated animals had lower lipid content and increased collagen deposition, features which correlate with a more stable plaque phenotype. Influenza vaccination also resulted in an antiinflammatory plasma cytokine pattern.…”

“…However, a study using ApoE À/À mice found no significant effect on atherosclerosis burden or plaque morphology following exposure to the polysaccharide pneumococcal vaccine. 140 Furthermore, studies in humans have so far been unable to demonstrate that pneumococcal vaccination elicits anti-oxLDL antibody production. 147,148 Potential pharmacological intervention strategies Preventing infection episodes by improving the uptake of pneumococcal and influenza vaccination in patients with established cardiovascular risk factors could play an important role in reducing infection-associated ACS.…”

Infection and Atherosclerosis Development

“…Alternatively, others have suggested that the protective effect of vaccination occurs by preventing influenza infection, which is known to promote a procoagulant state (152). Interestingly, a study designed to assess the effect of vaccination on atherosclerotic plaque development in hyperlipidemic mice demonstrated that mice receiving influenza vaccine developed smaller lesions with lower lipid content but had increased smooth muscle cells and collagen deposition in comparison to animals receiving a pneumococcus vaccine or no vaccine (153). Additionally, decreased levels of pro-inflammatory cytokines (IFN-γ, TNF-α, IL10) and higher levels of the anti-inflammatory cytokine IL-4 were noted in the influenza vaccinated group (153).…”