Abstract: Peptide antagonists of zonulin are disclosed, as well as methods for the use of the same. The peptide antagonists bind to the zonula occludens receptor, yet do not physiologically modulate the opening of mammalian tight junctions.

Abstract: “Black holes” in the genomes of bacterial pathogens represent deletions of “anti-virulence” genes, i.e. genes that are detrimental to a pathogenic lifestyle. Identification of the missing genetic loci in the “black hole” identifies genes that are incompatible with the bacteria's pathogenicity. These genes, their gene products, and compounds generated by the enzymatic action of these gene products represent potential new compounds that are inhibitory to the bacterial pathogen and thus useful as pharmaceuticals. The utility of this concept is demonstrated in the missing gene for lysine decarboxylase, and the resulting inhibitory activity of cadaverine (the diaminoalkyl reaction product of lysine decarboxylase) on the Shigella enterotoxins. Diaminoalkyl compounds are therefore potent inhibitors of E. coli and Shigella spp. enterotoxins Lysine decarboxylase generated from the gene cadA results in attenuation of the enterotoxic effects.

Abstract: Peptide antagonists of zonulin are disclosed, as well as methods for the use of the same. The peptide antagonists bind to the zonula occludens receptor, yet do not physiologically modulate the opening of mammalian tight junctions.

Abstract: Peptide antagonists of zonulin are disclosed, as well as methods for the use of the same. The peptide antagonists bind to the zonula occludens receptor, yet do not physiologically modulate the opening of mammalian tight junctions.

Abstract: “Black holes” in the genomes of bacterial pathogens represent deletions of “anti-virulence” genes, i.e. genes that are detrimental to a pathogenic lifestyle. Identification of the missing genetic loci in the “black hole” identifies genes that are incompatible with the bacteria's pathogenicity. These genes, their gene products, and compounds generated by the enzymatic action of these gene products represent potential new compounds that are inhibitory to the bacterial pathogen and thus useful as pharmaceuticals. The utility of this concept is demonstrated in the missing gene for lysine decarboxylase, and the resulting inhibitory activity of cadaverine (the diaminoalkyl reaction product of lysine decarboxylase) on the Shigella enterotoxins. Diaminoalkyl compounds are therefore potent inhibitors of E. coli and Shigella spp. enterotoxins. Lysine decarboxylase generated from the gene cadA results in attenuation of the enterotoxic effects.

Abstract: Receptors for the zonula occludens toxin of Vibrio cholera, as well as methods involving the use of the same are disclosed.

Abstract: A substantially pure mammalian protein, hereinafter "zonulin", that is a physiological modulator of mammalian tight junctions is disclosed, as well as methods for the use of the same.

Abstract: Receptors for the zonula occludens toxin of Vibrio cholera, as well as methods involving the use of the same are disclosed.

Abstract: A nasal dosage composition for nasal delivery comprising (A) a therapeutic agent; and (B) zonula occludens toxin, as well as a method for the use of the same.

Abstract: A membrane-associate protein which is present on the surface of, inter alia, intestinal epithelia cells, is disclosed. The protein acts as a receptor for the zonula occludens toxin of Vibrio cholera, and is related to the modulation of intestinal tight junctions. Also disclosed are methods for the use of the same to screen for analogs of Vibrio cholera zonula occludens toxin.

Abstract: An oral dosage composition for intestinal delivery of a therapeutic agent comprising:(A) a therapeutic agent selected from the group consisting of a drug compound, a biologically active peptide and a vaccine; and(B) an intestinal absorption enhancing effective amount of purified Vibrio cholera zonula occludens toxin.

Abstract: Substantially pure enterotoxins of Shigella flexneri 2a are described, along with a method for obtaining the same, antibodies having binding specificity to the enterotoxins and a method for use of the enterotoxins to develop a non-reactogenic Shigella flexneri 2a vaccine candidate.

Abstract: An oral dosage composition for intestinal delivery comprising (A) a biologically active ingredient; and (B) zonula occludens toxin, as well as a method for the use of the same.

Abstract: Substantially pure enterotoxins of Shigella flexneri 2a are described, along with a method for obtaining the same, antibodies having binding specificity to the enterotoxins and a method for use of the enterotoxins to develop a non-reactogenic Shigella flexneri 2a vaccine candidate.

Abstract: Methods of isolating deletion mutants of Vibrio cholerae. In one method, the deletion is predetermined by digestion with restriction endonucleases of known specificity. The deletions are inserted into the Vibrio cholerae chromosome by in vivo recombination between a plasmid carrying the desired deletion, with adjacent flanking sequences, and the Vibrio cholerae chromosome. In another method, an initial in vivo recombination event of homologous sequences from the recombinant plasmid into the chromosome provides a selectable marker at this site. A second in vivo recombination event between homologous flanking sequences results in excision of proficient genes from the chromosome with the end product being a deletion mutation. Also provided are methods for the isolation and characterization of a new Vibrio cholerae strain having a deletion in the ctx gene, as defined by Acc I, Xba I, Cla I and/or restriction endonuclease sites and further having a deletion in the gene encoding zonula occludens toxin (zot).

Abstract: Substantially pure enterotoxins of Shigella flexneri 2a are described, along with a method for obtaining the same, antibodies having binding specificity to the enterotoxins and a method for use of the enterotoxins to develop a non-reactogenic Shigella flexneri 2a vaccine candidate.