Eliminating the hepatitis C virus without treatment can lead to an increase in complications

A team from the Carlos III Health Institute (ISCIII) has analyzed how people who clear hepatitis C virus (HCV) infection without treatment could be at higher risk of suffering from liver disease and other types of pathologies. Approximately 25% of patients with acute HCV infection experience spontaneous healing within the first six months.

The research, published in the journal Immunity and agingtried to confirm the risk that these individuals, after spontaneous healing, are more likely to develop inflammatory processes and cellular aging that would lead to hepatic and extrahepatic complications.

To this end, the group from the National Center for Microbiology evaluated the plasma levels of biomarkers related to the so-called immune checkpoints, molecules that help prevent excessive immune reactions against an infection.

They also verified markers of the senescence-associated secretory phenotype (SASP), a process in which cells release pro-inflammatory factors associated with cell death (apoptosis). Both analyzes were carried out on 56 people: 32 had a spontaneously resolved HCV infection and 24 had not suffered an infection.

The results suggest that patients called spontaneous HCV clearers have elevated levels of proteins related to senescence and immune system activation even two years after clearing the infection, which could have implications for higher risk to suffer from various diseases in the future. This risk appears to be greater in men than in women.

The authors explain that this study is particularly valuable because studies of this type are very rare, as many of the people who have cleared the disease without treatment are asymptomatic and do not know that they had the infection, resulting in a lack of infections provides scientific knowledge on this topic.

Path to a future vaccine against the virus

They add that the results could be particularly useful for considering the possible design of a controlled human infection model that would facilitate the development of a vaccine against the hepatitis C virus, an option for which further evidence is still needed.

Controlled human infection involves intentionally infecting healthy volunteers to test the effectiveness of potential vaccines or treatments.

This could alleviate the shortage of immunocompetent animal models for research, which would speed up research, reduce costs and improve the process of developing vaccines or treatments. However, experts recall that there is still little data on the possible effects of acute HCV infection in the general population.

However, this study suggests that deregulation at the immune level occurs not only after chronic infection with this specific virus, but also occurs in people who have had and survived an acute infection.

These data, together with the lack of further evidence, could complicate the possibility of controlled infection in humans due to possible associated risks. Therefore, the authors insist on the need to further research this matter to assess these possible risks.