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Assessing the impact of mRNA vaccination in chronic inflammatory murine model
Seonghyun Lee1,2, Jisun Lee1, Sun-Hee Cho3
1Department of Medical and Biological Sciences, The Catholic University of Korea, Gyeonggi-do, Bucheon, Republic of Korea.
Abstract:
The implications of administration of mRNA vaccines to individuals with chronic inflammatory diseases, including myocarditis, rheumatoid arthritis (RA), and inflammatory bowel disease (IBD), are unclear. We investigated mRNA vaccine effects in a chronic inflammation mouse model implanted with an LPS pump, focusing on toxicity and immunogenicity. Under chronic inflammation, mRNA vaccines exacerbated cardiac damage and myocarditis, inducing mild heart inflammation with heightened pro-inflammatory cytokine production and inflammatory cell infiltration in the heart. Concurrently, significant muscle damage occurred, with disturbances in mitochondrial fusion and fission factors signaling impaired muscle repair. However, chronic inflammation did not adversely affect muscles at the vaccination site or humoral immune responses; nevertheless, it partially reduced the cell-mediated immune response, particularly T-cell activation. These findings underscore the importance of addressing mRNA vaccine toxicity and immunogenicity in the context of chronic inflammation, ensuring their safe and effective utilization, particularly among vulnerable populations with immune-mediated inflammatory diseases.
Insights
mRNA vaccines may worsen heart and muscle damage in individuals with chronic inflammatory diseases. Further research is needed to ensure safe vaccine use in these vulnerable populations.
Area of Science:
- Immunology
- Toxicology
- Cardiology
Background:
- The safety of mRNA vaccines in individuals with chronic inflammatory diseases like myocarditis, rheumatoid arthritis (RA), and inflammatory bowel disease (IBD) remains unclear.
- Chronic inflammatory conditions can alter immune responses and potentially impact vaccine efficacy and safety.
Purpose of the Study:
- To investigate the toxicity and immunogenicity of mRNA vaccines in a mouse model of chronic inflammation.
- To assess the effects of mRNA vaccination on cardiac and muscle tissue, as well as immune responses in an inflamed state.
Main Methods:
- A chronic inflammation mouse model was established using an LPS pump.
- Mice received mRNA vaccines, and subsequent cardiac and muscle damage, pro-inflammatory cytokine levels, inflammatory cell infiltration, mitochondrial dynamics, and immune responses (humoral and cell-mediated) were analyzed.
Main Results:
- mRNA vaccination exacerbated cardiac damage and myocarditis, characterized by increased pro-inflammatory cytokines and inflammatory cell infiltration in the heart.
- Significant muscle damage was observed, linked to disruptions in mitochondrial fusion and fission signaling, impairing muscle repair.
- While vaccination site muscles and humoral immunity were unaffected, cell-mediated immunity, particularly T-cell activation, was partially reduced.
Conclusions:
- mRNA vaccines can increase cardiac and muscle toxicity in the context of chronic inflammation.
- These findings highlight the need to evaluate mRNA vaccine safety and immunogenicity in patients with immune-mediated inflammatory diseases.
- Further research is crucial for the safe and effective deployment of mRNA vaccines in vulnerable populations with chronic inflammatory conditions.
