Torque teno virus in liver diseases: On the way towards unity of view

Core Tip

Core tip: The review is dedicated to torque teno virus (TTV) discovered in the late 20th century. It presents data on the morphofunctional properties of the virus, its immunobiology, prevalence, transmission routes, possible replication sites, methods for diagnosis and co-infection in liver diseases. The authors tried to analyze the information accumulated in the literature on these issues and to show the evolution of views on the importance of the virus to humans: From its hepatotropism to virome and a marker for the human immune status. Along with this, the review gives data suggesting that there are biochemical and histological changes in the liver and bile duct epithelium during TTV monoinfection. On the one hand, this information points to the possible replication of the virus in the cells of the liver and the epithelium of the bile ducts. On the other hand, the high prevalence of TTV in the population indicates its persistence in the body as a virome and a non-pathogenic virus. Moreover, the fortunately rare identification of the damaging effect of the virus on the cells of the liver and the epithelium of the bile ducts may be indirect evidence of its conditionally pathogenic properties.