Novel Hepatitis C Vaccine Induces T Cell Responses
HealthDay News—Adenovirus-based vaccines can generate strong, broad, long-lasting, and functional T cell responses against hepatitis C virus (HCV) in healthy people, according to a study published in the Jan. 4 issue of Science Translational Medicine.
Eleanor Barnes, MD, of the University of Oxford in the United Kingdom, and colleagues used a recombinant adenoviral vector strategy in a Phase 1 trial of an HCV vaccine in healthy human volunteers. Two adenoviral vectors expressing NS proteins from HCV genotype 1B were constructed based on rare serotypes (human adenovirus 6 and chimpanzee adenovirus 3).
The researchers found that both of the vectors primed T cell responses against HCV proteins. The T cell responses targeted multiple proteins and were capable of recognizing heterologous strains (genotypes 1A and 3A). HCV-specific T cells included both CD4+ and CD8+ T cell subsets and secreted interleukin-2, interferon-gamma, and tumor necrosis factor-alpha. The T cell response could be sustained for at least a year after boosting with the heterologous adenoviral vector. Examination using major histocompatibility complex peptide tetramers revealed T cells (central and effector) that retained polyfunctionality and proliferative capacity.
"These data indicate that an adenoviral vector strategy can induce sustained T cell responses of a magnitude and quality associated with protective immunity and open the way for studies of prophylactic and therapeutic vaccines for HCV," the authors write.
Several authors disclosed financial ties to pharmaceutical companies.