H7N9 caused a serious outbreak in China in 2013. Since that time, scientists have been concerned about its high rate of lethality as well as its pandemic potential, making developing an H7N9 vaccine a top priority.
Unfortunately, none of the vaccine candidates has produced strong immune responses to counteract the virus. Researchers have discovered this is because the virus uses immune camouflage to remain undetected.
“The original observation of low H7N9 T-cell epitope content was made before any data were available on vaccine efficacy,” Anne De Groot, EpiVax Inc. CEO and senior author and director of the Institute for Immunology and Informatics at the University of Rhode Island, said. “It turns out that we were absolutely correct. By comparison with H1N1 and H3N1, H7N9 vaccines are far less immunogenic.”
This discovery could change the approach to developing vaccines for other diseases as well.
“It appears that this new mechanism of immune escape may be common to quite a few human pathogens,” De Groot said. “We are working on validating several other peptides, some from common seasonal strains of influenza and some from pathogens like HIV and M. tuberculosis that do live for a long time inside their hosts.”
Further details are available in Human Vaccines & Immunotherapeutics.
Source: Vaccine News daily