Posted on March 11, 2015
Source: Health Canal
Using a specially selected library of different hepatitis C viruses, a team of researchers led by Johns Hopkins scientists has identified tiny differences in the pathogens’ outer shell proteins that underpin their resistance to antibodies. The findings, reported in the January issue of the Journal of Clinical Investigation, suggest a reason why some patients’ immune systems can’t fend off hepatitis C infections, and they reveal distinct challenges for those trying to craft a successful vaccine to prevent them. Due to concerns about the rising costs of newly available hepatitis C drugs, researchers are looking to a vaccine as a more viable and less costly option.
The systems of some people who become infected with the liver-ravaging hepatitis C virus launch a robust immune attack, producing antibodies that attach to a broad array of the germs with different genetic makeups. About one-third of these individuals successfully clear the pathogen from their bodies. However, says Justin Bailey, M.D., Ph.D., assistant professor of medicine in the Division of Infectious Diseases in the Johns Hopkins University School of Medicine, no single antibody has been found that can neutralize all strains of hepatitis C virus.
To better understand how hepatitis C viruses avoid even the most broadly neutralizing antibodies, Bailey, along with Stuart C. Ray, M.D., professor of medicine in the Division of Infectious Diseases in the Johns Hopkins University School of Medicine, and their colleagues tested the power of 18 antibodies known to broadly attack the virus against a library of 19 viral strains that make up about 94 percent of the genetic variability of hepatitis C viruses in the most common genetic group, called genotype 1.