Review details potential of influenza vaccination to modulate inflammaging via trained tolerance

A newly published literature review suggests that inactivated influenza vaccines may modulate chronic inflammaging by inducing persistent epigenetic remodeling in myeloid cells, potentially conferring broad heterologous protection against age-related diseases.

Researchers published a review in Ageing Research Reviews analyzing multiomic, preclinical, and epidemiological evidence on the heterologous effects of influenza vaccination.

The paper notes that influenza vaccination is associated with clinical benefits extending beyond pathogen-specific protection, including reduced cardiovascular morbidity and mortality, lower dementia incidence, fewer cardio-renal complications, and improved survival in older cohorts.

The review highlights single-cell multiomic evidence showing that inactivated influenza vaccines induce persistent epigenetic remodeling in monocytes and myeloid dendritic cells lasting up to six months.

This process, characterized as 'trained tolerance,' represents a regulatory recalibration of innate reactivity that may counter the myeloid axis dysfunction central to inflammaging and frailty.

The authors emphasize that a direct effect on chronic low-grade inflammation remains unproven due to key epidemiological uncertainties, including healthy-vaccinee bias, a lack of frailty stratification, and sparse evidence in adults aged 75 to 80 years and older.

Inflammaging is a recognized systemic driver of diverse chronic diseases of aging, including vascular pathology and neurodegeneration.

Demonstrating that the innate immune system in older adults can undergo sustained epigenetic reprogramming opens new therapeutic pathways for actively modulating immune senescence.

The proposed framework of trained tolerance suggests that existing, highly scalable clinical tools could be optimized or mimicked to systematically lower chronic systemic inflammation.

The conceptual shift from simple pathogen prevention to active epigenetic modulation of the immune system may influence R&D pipelines focused on immunosenescence and age-related chronic inflammation.

The reliance on observational human data and mouse models highlights the persistent translational gap in establishing causal relationships for anti-inflammaging therapies.

The emphasis on healthy-vaccinee bias and the necessity of frailty stratification underscores the complex clinical trial design and regulatory pathways required to validate therapies targeting systemic aging markers.

Clinical and mechanistic trials specifically designed with frailty stratification to directly measure the vaccine's impact on chronic low-grade inflammatory profiles in cohorts aged 75 to 80 years and older.