摘要:
The present invention provides a novel composition which is a hybrid heat labile enterotoxin comprising the A-subunit of the heat labile toxin of Escherichia coli (LT-A) and the B-subunit of the cholera enterotoxin of Vibrio cholerae (CT-B). The hybrid toxin is designated LT-A/CT-B. The LT-A subunit, the CT-B subunit, or both subunits of the hybrid toxin may be mutant subunits, e.g., differing from wild-type subunits by amino acid substitutions, deletions or additions. Also provided are methods of using the novel LT-A/CT-B comprising compositions of the invention as adjuvants for vaccines, methods of making the LT-A/CT-B hybrid holotoxin, and kits.
摘要:
The oral antigens and adjuvants of the present invention are produced in transgenic plants and then administered through the consumption of the transgenic plant. DNA sequences both natural and synthetic encoding for the expression of immunogenic agents which are capable of causing an immune response in animals when fed in edible plants, plant tissues, or derived plant materials are constructed, and plants transformed for stable or transient expression in plant cells. The present invention provides the first known functional method for immunizing animals via transgenic plants, where the plants express bacterial antigens that act as both immunogen and adjuvants when the transgenic plant material expressing the antigens is fed to animals.
摘要:
The present invention is directed towards a novel composition which is a genetically distinct mutant of E. coli heat-labile enterotoxin (LT). Specifically, the mutant LT designated LT(R192G/L211A) is modified by two amino acid substitutions, i.e., the arginine at amino acid position 192 is replaced by glycine and the leucine at amino acid position 211 is replaced by alanine. The invention relates to compositions and methods for use of the novel double mutant of LT as an adjuvant.
摘要:
A conjugate, which is the reductive amination product of an immunogenic capsular polymer fragment, having a reducing end and derived from the capsular polymer of a bacterial pathogen, and the non-toxic polypeptide binding subunit of the heat-labile enterotoxin of Escherichia coli (LT-BNT). Also disclosed, are methods for the preparation of the conjugates and for the preparation of vaccines containing the conjugates which elicits an effective level of antibodies in humans. By administering an immunogenic amount of the conjugates, active immunization against systematic infection in young mammals caused by bacterial pathogens can be induced.
摘要:
Methods and compositions are provided herein for the use of a novel mutant form of E. coli heat-labile enterotoxin which has lost its toxicity but has retained its immunologic activity. This enterotoxin is used in combination with an unrelated antigen to achieve an increased immune response to said antigen when administered as part of a vaccine preparation.
摘要:
Methods and compositions are provided herein for the use of a novel mutant form of E. coli heat-labile enterotoxin which has lost its toxicity but has retained its immunologic activity. This enterotoxin is used in combination with an unrelated antigen to achieve an increased immune response to said antigen when administered as part of an oral vaccine preparation.
摘要:
Methods and compositions are provided for the cloning and expression of plasmids bearing genes coding for the non-toxic subunit of the heat-laible enterotoxin (LT-B) of E. coli. These plasmids may be cloned into stable avirulent strains of Salmonella typhi and used to make oral bivalent vaccines. Such vaccines may be used to prevent typhoid fever and cholera-like enterotoxin-induced diarrheal disease.
摘要:
There is disclosed a novel immunogen which can be used for immunological protection against acute diarrheal disease caused by enterotoxigenic strains of Escherichia coli. The novel immunogen is provided by cross-linking the E. coli heat-stable enterotoxin with the E. coli heat-labile enterotoxin (either the complete holotoxin or just the B subunit of this toxin) by a conjugation process in the presence of a conjugating agent, typically the water soluble carbodiimide, 1-ethyl-3-(3-diamethylaminopropyl) carbodiimide. This results in a unique new molecule in that the toxic properties of each individual toxin are greatly reduced, the heat-labile toxin (or its B subunit) retains its antigenicity, and the heat-stable toxin acquires immunogenicity as a function of the reaction. Immunization with the cross-linked immunogen provides immunological protection in mammals against water secretion induced by strains of E. coli which produce the heat-labile or heat-stable enterotoxins, either singly or together.
摘要:
Methods and compositions are provided herein for the se of a novel mutant form of E. coli heat-labile enterotoxin which has lost its toxicity but has retained its immunologic activity. This enterotoxin is used in combination with an unrelated antigen to achieve an increased immune response to said antigen when administered as part of an oral vaccine preparation.
摘要:
Methods and compositions are provided for the cloning and expression of genes coding for the non-toxic subunit of the heat-labile enterotoxin (LT-B) of E. coli. The LT-B thus produced may be formulated for use as an immunogen in vaccines. Specific antibodies produced by this invention may be used in diagnostic tests for the detection of Vibrio cholerae or LT positive enterotoxigenic E. coli. The antibodies of this invention may further be formulated into passive vaccines for the prophylactic or therapeutic protection of human beings or other mammalian species against diarrheal diseases caused by Vibrio cholerae or by the LT positive enterotoxigenic E. coli or other bacteria.