New antibody halts Hepatitis C infection

A human monoclonal antibody developed by researchers has neutralised the Hepatitis C virus (HCV) and prevented infection in a pre-clinical animal model of the disease.

Monoclonal antibody is any of a class of antibodies produced in the lab by a single clone of cells or a cell line and consisting of identical antibody molecules.

"This antibody shows significant efficacy against the virus," said Donna Ambrosino, executive director of the University of Massachusetts Biologic Laboratories (MBL) and professor of paediatrics at its medical school (UMMS).

MBL scientists injected transgenic (genetically modified) mice with elements of HCV and then sought individual human antibodies produced in the mice that would recognise and bind to the HCV's outer coat, known as the glycoprotein.

Once they found human antibodies that looked promising, they evaluated in vitro (lab) the ability of those antibodies to neutralise the virus and selected an antibody for further characterisation.

Collaborative work with clinical researchers from the department of medicine at the UMMS Worcester campus demonstrated that this antibody, now known as MBL-HCV1, was able to bind tightly with all genotypes (group of organisms sharing a specific genetic constitution) of HCV tested from infected patient samples.

MBL-HCV1 was then tested off-site on three primates. In that study, one animal received no antibody, one a low dose of the new antibody, and one a higher dose.

Then all three animals were exposed to HCV. The animals with low or no antibody dosages developed HCV infections, but the animal with the higher dose was protected.

Subsequently, researchers gave the high dose to the animal that received no antibody, and in that case the HCV was cleared from that animal's system.

"These results are encouraging as a possible treatment for HCV infected patients, but more work needs to be done before we know how effective it will be in people," Ambrosino noted.

HCV attacks the liver and can eventually lead to liver failure. Globally, as many as 170 million people are estimated to suffer from HCV infection. For the most serious cases of HCV that do not respond to antiviral drugs, liver transplantation is the only option, said an UMMS release.

Details of the research were presented at the 44th Annual Meeting of the European Association for the Study of the Liver (EASL) in Denmark.