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

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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