Role of Trained Immunity in Heath and Disease.

Purpose of review: This review aims to explore the role of immune memory and trained immunity, focusing on how innate immune cells like monocytes, macrophages, and natural killer cells undergo long-term epigenetic and metabolic rewiring. Specifically, it examines the mechanisms by which trained immunity, often triggered by infection or vaccination, could impact cardiac processes and contribute to both protective and pathological responses within the cardiovascular system.

Recent findings: Recent research demonstrates that vaccination and infection not only activate immune responses in circulating monocytes and tissue macrophages but also affect immune progenitor cells within the bone marrow environment, conferring lasting protection against heterologous infections. These protective effects are attributed to epigenetic and metabolic reprogramming, which enable a heightened immune response upon subsequent encounters with pathogens. However, while trained immunity is beneficial in combating infections, it has been linked to exacerbated inflammation, which may increase susceptibility to cardiovascular diseases, including atherosclerosis and heart failure. Our review highlights the dual nature of trained immunity: while it offers protective advantages against infections, it also poses potential risks for cardiovascular health by promoting chronic inflammation. Understanding the molecular mechanisms underlying immune memory's impact on cardiac processes could lead to new therapeutic strategies to mitigate cardiovascular diseases, such as atherosclerosis, heart failure, and diabetes. These insights build the grounds for future research to balance the benefits of trained immunity with its potential risks in cardiovascular disease management.