Science

Type 1 interferon augments murine response to DNA-based anti-HCV vaccine

Last Updated: 2005-02-03 16:49:41 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Mice treated with type 1 interferon have enhanced responses to DNA vaccination against hepatitis C virus core protein, according to a report in the February issue of the Journal of Medical Virology.

At Brown Medical School in Providence, Rhode Island, Dr. Stephan Gehring and colleagues treated mice with two types of recombinant type 1 interferon proteins: hybrid interferon alpha A/D (also referred to as universal type 1 interferon), and human pegylated interferon alpha-2a. In addition, the researchers tested the effect of administration of a plasmid expressing murine interferon-alpha.

According to the article, analysis of conventional cytotoxic T lymphocyte assays and an in vivo tumor challenge model showed that low doses of hybrid interferon alpha A/D and pegylated interferon "augmented three to fourfold the cellular immune response to DNA-based vaccination."

"Importantly," the investigators add, "augmentation occurred within a narrow concentration range." Whereas low doses of both of these types of interferon induced strong augmentation of vaccination, increasing the doses resulted in significantly decreased augmentation.

Administration of the plasmid expressing murine interferon-alpha "strongly suppressed the specific cytotoxic T lymphocyte activity" of the vaccine, the researchers report.

These findings, they conclude, "demonstrate that the immunomodulatory properties of interferon-alpha can be exploited to augment DNA based immunization, but it is important to consider the effects of dose on both cellular and humoral immune response for optimal augmentation."

J Med Virol 2005;75:249-257