Adherence to a Supplemented Mediterranean Diet Drives Changes in the Gut Microbiota of HIV-1-Infected Individuals.

OBJECTIVE: The health effects of a supplemented Mediterranean diet (SMD) with extra-virgin olive oil (EVOO) and nuts are well documented in non-HIV-infected individuals. We hypothesised that the benefits of an SMD could be mediated by changes in the gut microbiota, even in those with an altered intestinal microbiota such as people living with HIV. DESIGN: Individuals living with HIV (n = 102) were randomised to receive an SMD with 50 g/day of EVOO and 30 g/day of walnuts (SMD group) or continue with their regular diet (control group) for 12 weeks. METHODS: Adherence to the Mediterranean diet was assessed using the validated 14-item MD-Adherence-Screener (MEDAS) from the PREDIMED study. A sub-study classifying the participants according to their MEDAS scores was performed. RESULTS: The lipid profile was improved in the SMD group vs. that in the control group (delta-total cholesterol and delta-B-lipoprotein). The immune activation (CD4+HLADR+CD38+ and CD8+HLADR+CD38+ cells) and IFN-γ-producing T-cells significantly decreased at week 12 compared to the baseline in the SMD group but not in the control group. The gut microbiota in those from the high-adherence group presented significantly high diversity and richness at the end of the intervention. Succinivibrio and Bifidobacterium abundances were influenced by the adherence to the MD and significantly correlated with Treg cells. CONCLUSION: The Mediterranean diet improved metabolic parameters, immune activation, Treg function, and the gut microbiota composition in HIV-1-infected individuals. Further, Mediterranean diet increased the Bifidobacterium abundances after the intervention, and it was associated to a beneficial profile.

A safe, effective and affordable HIV vaccine--an urgent global need.

The need for a safe, effective and affordable HIV vaccine has never been greater. In 2004 almost five million people became infected with HIV. In addition, providing access to antiretrovirals in Africa remains a huge challenge. A successful vaccine against HIV will probably need to stimulate the innate immune system, generate high levels of neutralizing antibodies, induce strong cellular immune responses and mucosal immunity, and should induce broad-spectrum immunity able to cover all HIV subtypes. In this review, we describe the limitations and challenges of developing a safe and effective HIV vaccine. We also emphasize possible approaches for overcoming immune escape in HIV infection, the lessons learned from the clinical trials of HIV-1 candidate vaccines, and the most important scientific highlights of the Keystone 2005 Symposium. When an effective vaccine is eventually found, we will face the enormous task of making it accessible to those who need it most.