Expression of Amyloid-β1–40 and 1–42 Peptides in Capsicum annum var. angulosum for Oral Immunization

Abstract

Alzheimer’s disease (AD), the leading cause of dementia in the elderly population, still remains without an effective treatment. The accumulation and deposition of the amyloid-β peptide(Aβ) in the brain is thought to be a key event in the pathogenesis of AD. Recently, a novel exciting technology has been investigated to combat AD: new immunotherapeutic approaches have been described that are based on vaccination with the Aβ peptide itself, and this has been shown to induce functionally beneficial anti-Aβ antibody responses in different transgenic animal models of AD. Here we report the high level expression of GFP-Aβ1–40 and 1–42 peptides in Capsicum annum var. angulosum (green pepper) using a new tomato mosaic tobamovirus-based hybrid replication vector. After preinoculation of Nicotiana benthamiana plants with the in vitro transcript of the vector, the isolated virions were used to inoculate green pepper, which accumulated the GFPAβ1–40 or 1–42 fusion proteins to a level of 100 μg/g of leaves 7 days after inoculation. These results make it possible to test whether oral immunization by feeding plant samples could stimulate antibody production against Aβ peptides.