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Immunogenicity of recombinant LT-B delivered orally to humans in transgenic corn. Vaccine

Center for Vaccine Development, University of Maryland School of Medicine, 685 West Baltimore Street, Baltimore, MD 21201, USA.
Vaccine (Impact Factor: 3.49). 11/2004; 22(31-32):4385-9. DOI: 10.1016/j.vaccine.2004.01.073
Source: PubMed

ABSTRACT Previous clinical studies have demonstrated the feasibility of using edible transgenic plants to deliver protective antigens as new oral vaccines. Transgenic corn is particularly attractive for this purpose since the recombinant antigen is stable and homogeneous, and corn can be formulated in several edible forms without destroying the cloned antigen. Transgenic corn expressing 1 mg of LT-B of Escherichia coli without buffer was fed to adult volunteers in three doses, each consisting of 2.1 g of plant material. Seven (78%) of nine volunteers developed rises in both serum IgG anti-LT and numbers of specific antibody secreting cells after vaccination. Four (44%) of nine volunteers also developed stool IgA. Transgenic plants represent a new vector for oral vaccine antigens.

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    • "Intestinal mucosa represents an attractive target for oral delivery of immunogens and for mucosal vaccination. Several oral strategies, using biodegradable polymeric particles [6] [7], liposome [8], bacterial ghost [9], plant lectins [10] [11], adjuvanted vaccines [12] or transgenic plants [13] [14], have been adopted to protect the antigens in the gastrointestinal tract and to increase uptake by DCs, causing their maturation and their migration to the intrafollicular areas. PLA (poly(lactic acid)) or PLGA (poly(lactic-co-glycolic acid)) nanoparticles are suitable protein carriers offering antigen protection , increased penetration across mucosal surface and controlled release of encapsulated antigen [15]. "
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    Vaccine 03/2011; 29(20):3655-61. DOI:10.1016/j.vaccine.2011.03.012 · 3.49 Impact Factor
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    • "The expression level of both B subunits, measured by quantitative ELISA, varied between 0.5 and 2.7% of the total soluble protein (TSP), which represents about 1.3 mg/g seed recombinant protein. According to Tacket et al. (2004) this level of protein expression is sufficient to generate a sizeable amount of antigen after the consumption of a few milligrams of seeds, and the transgenic rice lines can be used for the production of rice seed-based edible vaccines. "
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    Acta Agronomica Hungarica 03/2010; 57(1):55-64. DOI:10.1556/AAgr.58.2010.1.7
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    • "In addition, the elicited antibody response is capable of partial protection against LT challenge, and results in an immunogenic response in human subjects (Tacket et al., 1998). Similar findings have been reported for maize-derived LTB (Chikwamba et al., 2002a,b; Tacket et al., 2004). Recently, our research group has reported on the expression of a synthetic LTB gene in carrots, resulting in LTB-containing tubers capable of inducing a mucosal immune response and providing protection against the cholera toxin in mice (Rosales-Mendoza et al., 2007, 2008). "
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