Cucumber mosaic virus as the expression system for a potential vaccine against Alzheimer's disease.

A primary therapeutic goal in Alzheimer's disease (AD) is to reduce the quantity of amyloid ß protein (Aß) present in the brain. To develop an effective, safe system for vaccination against Alzheimer's disease, the plant virus Cucumber mosaic virus (CMV) was engineered genetically to express Aß-derived fragments that stimulate mainly humoral immune responses. Six chimeric constructs, bearing the Aß1-15 or the Aß4-15 sequence in positions 248, 392 or 529 of the CMV coat protein (CP) gene, were created. Viral products proved to be able to replicate in their natural host. However, only chimeric Aß1-15-CMVs were detected by Aß1-42 antiserum in Western blot analysis. Experimental evidence of Immunoelectron microscopy revealed a complete decoration of Aß1-15-CMV(248) and Aß1-15-CMV(392) following incubation with either anti-Aß1-15 or anti-Aß1-42 polyclonal antibodies. These two chimeric CMVs appear to be endowed with features making them possible candidates for vaccination against Alzheimer's disease.

In vitro stability of Cucumber mosaic virus nanoparticles carrying a Hepatitis C virus-derived epitope under simulated gastrointestinal conditions and in vivo efficacy of an edible vaccine.

The Cucumber mosaic virus (CMV) is an isodiametric plant virus with an extremely wide host range, present worldwide. CMV chimeric particles (R9-CMV), engineered to express a 27-aa synthetic peptide derived from Hepatitis C virus (HCV), were demonstrated to be stable under simulated gastric and intestinal conditions. Then the possibility of inducing a humoral immune response in rabbits fed with R9-CMV infected lettuce plants was demonstrated, suggesting that this system could function as a confirming tool of a bioreactor for the production of a stable edible vaccine against HCV.