Delivery of subunit vaccines in maize seed

Abstract

The use of recombinant gene technologies by the vaccine industry has revolutionized the way antigens are generated, and has provided safer, more effective means of protecting animals and humans against bacterial and viral pathogens. Viral and bacterial antigens for recombinant subunit vaccines have been produced in a variety of organisms. Transgenic plants are now recognized as legitimate sources for these proteins, especially in the developing area of oral vaccines, because antigens have been shown to be correctly processed in plants into forms that elicit immune responses when fed to animals or humans. Antigens expressed in maize (Zea mays) are particularly attractive since they can be deposited in the natural storage vessel, the corn seed, and can be conveniently delivered to any organism that consumes grain. We have previously demonstrated high level expression of the B-subunit of Escherichia coli heat-labile enterotoxin and the spike protein of swine transmissible gastroenteritis in corn, and have demonstrated that these antigens delivered in the seed elicit protective immune responses. Here we provide additional data to support the potency, efficacy, and stability of recombinant subunit vaccines delivered in maize seed.

Plant Bioreactors for the Antigenic Hook-Associated flgK Protein Expression

“…Nevertheless, the average amount of flgK was estimated to be about 0.6 mg per gram of seeds, corresponding to 0.33% of the total soluble protein in tobacco seeds. The obtained number of antigens (per gram of seeds), according to other authors, is sufficient for subsequent trials focusing on the in vivo evaluation of the oral administration of tobacco seeds transformed for flgK seedexpression (Lamphear et al, 2002;Streatfield et al, 2001). No cross-reacting proteins were identified in any of the wild-type seed extracts.…”

“…Plant systems represent a relatively inexpensive way for the expression and large-scale production of proteins rather than using industrial methods (fermentation of bacteria, yeast, cultured animal or human cell lines) and have the ability to carry out post-translational modifications similar to naturally-occurring systems (Streatfield, 2006). Several studies have shown that plants that have been engineered with genes encoding for antigenic proteins of various microorganisms correctly express the proteins that elicit the production of antibodies in mammalian hosts (Lamphear et al, 2002;Rossi et al, 2003aRossi et al, , 2003bPinotti et al, 2003). Plant-based vaccines offer different advantages (SalazarGonzales et al, 2013).…”

Comparison of Serum Humoral Responses Induced by Oral Immunization with the Hepatitis B Virus Core Antigen and the Cholera Toxin B Subunit

“…It has been shown that after freeze or air drying of Norwalk VLPs expressed in tomato fruits, specific IgG and IgA responses could still be induced in mice fed with these preparations (25,72). Moreover, the corn-expressed B subunit of heat-labile toxin, the S glycoprotein of transmissible gastroenteritis, and the lettuce-expressed measles virus hemagglutinin protein have all been shown to be stable for at least 1 year, even when stored at ambient temperatures (34,69). This suggests the potential for accessibility and use of these vaccines in developing countries, as cold chains are not required for antigen preservation.…”

Uso de vacinas no controle da coccidiose aviária

“…Porém este tipo de vacina tem o inconveniente da possibilidade de manifestação clínica da doença (LILLEHOJ et al, 2000a). Assim, com o advento da biologia molecular, diversos estudos têm sido desenvolvidos nesta área, visando a estimulação específica de células promotoras de imunidade consistente (LAMPHEAR, et al, 2002).…”