Earlier Hepatitis B Treatment In Young Patients May Yield Better Results

Scientists in Singapore have found that young patients with Hepatitis B are not immune tolerant as previously thought.

AsianScientist (Sep. 17, 2012) – Scientists in Singapore have found that young patients with Hepatitis B are not immune tolerant as previously thought, and that earlier treatment might yield a better response in this group.

Hepatitis B (HBV) is a viral infection that affects 400 million people worldwide, 75 percent of whom reside in Asia. In Singapore, it is estimated that one in 35 adults are carriers of the virus. The disease is spread by direct contact with the blood or body fluids of an infected person. While not all carriers are symptomatic, lifelong chronic infection carries the risk of serious health complications including liver cirrhosis (scarring of the liver), hepatocellular carcinoma, and liver failure.

Scientists from A*STAR’s Singapore Institute for Clinical Sciences (SICS), together with clinical collaborators from London, discovered for the first time that children and young patients with chronic Hepatitis B Virus infection (HBV carriers) do have a protective immune response, contrary to current belief, and hence can be more suitable treatment candidates than previously considered.

The findings, published in the journal Gastroenterology this month, were made by a team of scientists led by Professor Antonio Bertoletti, program director and research director of the infection and immunity programme at SICS, and could lead to a paradigm shift in the treatment of patients with chronic HBV.

Currently, international liver associations recommend delaying therapy until HBV carriers show clear signs of active liver disease, which generally appear after the age of 30. This is based on two assumptions – that young patients are unable to react to treatment because they do not mount a protective immune response to rid themselves of the virus, and that HBV infection is largely harmless in HBV carriers until they develop active liver disease.

However, Professor Bertoletti and his team showed that young patients are not immune tolerant as they possess HBV-specific T cells with the ability to produce distinct antiviral cytokines that help the body fight against HBV.

They also showed that the longer a patient is left untreated, the less effective their immune system becomes against HBV. This is due to repeated activation of T cells which induces a progressive state of T cell exhaustion, a state of immune system dysfunction that prevents optimal control of the infection and clearance of the virus from the body.

“Young patients infected with HBV are most at risk of developing chronic HBV but current guidelines mean that they are also the least likely to be treated. However, our findings suggest that it might be better to start treatment early as young people with their stronger immune system, respond better to treatment and are more able to clear the virus,” said Bertoletti.

The article can be found at: Kennedy PTF et al. (2012) Preserved T-Cell Function in Children and Young Adults With Immune-Tolerant Chronic Hepatitis B.

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Source: A*STAR.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Rebecca Lim is a Singaporean-born medical doctor practising in Melbourne, Austraia. She earned her MBBS degree from Monash University, Australia.

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