LAUSR

BACKGROUND The virome is a network of viruses normally inhabiting humans. It forms a conspicuous portion of the so-called microbiome, once generically referred to as resident flora. Indeed, viruses infecting humans without leading to clinical disease are increasingly recognized as part of the microbiome and have an impact on the development of our immune system. In addition, they activate inflammasomes, multiprotein complexes that assemble in cells and that are responsible for the downstream effects of sensing pathogens. OBJECTIVE This review aims at summarizing the evidence on the role of the virome in modulating inflammation and emphasizes evidence for Anelloviruses as useful molecular markers to monitor inflammatory processes and immune system competence. METHOD We carried out a review of the literature published in the last 5 years and summarized older literature to take into account ground-breaking discoveries concerning inflammasome assembly and virome. RESULTS A massive amount of data recently emerging demonstrate that the microbiome closely reflects what we eat, and many other unexpected variables. Composition, location, and amount of the microbiome have an impact on innate and adaptive immune defences. Viruses making up the virome contribute to shaping the immune system. Anelloviruses, the best known of such viruses, are present in most human beings, persistently without causing apparent disease. Depending on their interplay with such viruses, inflammasomes instruct host defences to tolerate or forfeit a specific microorganism. CONCLUSION The virome plays an important role in shaping human immune defences and contributes to inflammatory processes by quenching or increasing them.