Combination antiretroviral therapy has led to a dramatic improvement in life expectancy for people with HIV infection. However, co-infection with HCV remains a significant challenge. HCV is a major cause of chronic liver disease and cancer worldwide and is a leading cause of death in HIV co-infected individuals. To address this health issue, scientists on the EU-funded PEACHI project are developing vaccines to prevent HCV, HIV-1 and co-infection. They are employing simian adenovirus and modified vaccinia virus Ankara vector technology to stimulate potent immune responses to HIV-1 and HCV. The vaccines have been designed to focus the immune response towards conserved regions within HIV-1 and epitope-rich regions within HCV non-structural proteins. They will evaluate the safety and efficacy of these vaccines in healthy individuals without HIV-1 or HCV infections first, followed by HIV-1 positive HCV-uninfected adults who receive ART. Single-cell analyses will be performed to assess the quality of vaccine-induced T cell responses. The PEACHI consortium is also working on a novel vaccine technology that aims to improve the immunogenicity of existing vaccines. Their approach involves the use of a vaccine-encoded adjuvant, the human leukocyte antigen (HLA) class II-associated invariant chain, which is fused to the HCV proteins, and enhances HCV antigen presentation to immune cells. PEACHI scientists have focused initially on vaccine development and optimisation of the clinical trial protocols, together with training in good clinical practice, laboratory techniques and standard operating procedures. Efforts are ongoing to develop and optimise new immunology assays for analysis of the clinical trial samples. These should contribute significantly to the project objectives and may open new avenues for research into immune control of HIV-1 and HCV infections.
HIV, HCV, co-infection, vaccines, vector technology, T cell responses