| PATENT NUMBER | This data is not available for free |
| PATENT GRANT DATE | 31.12.02 |
| PATENT TITLE |
Polypeptide fragments capable of competition with Streptococcus mutans antigen I/II |
| PATENT ABSTRACT | Defined peptide subunits of Streptococcus mutans antigen I/II (SAI/II) are useful as agents to prevent and treat dental caries either by eliciting an immunological response or by preventing adhesion of S. mutans to the tooth |
| PATENT INVENTORS | This data is not available for free |
| PATENT ASSIGNEE | This data is not available for free |
| PATENT FILE DATE | December 9, 1999 |
| PATENT FOREIGN APPLICATION PRIORITY DATA | This data is not available for free |
| PATENT REFERENCES CITED |
Bell et al. 1992. Definition of an immunodominant T cell epitope in the envelope gp41 sequence of HIV-1. Clin. Exp. Immunol. vol. 87, pp. 37-45.* Adorini et al., "Mechanisms Influencing the Immunodominance of T Cell Determinants," J EXP MED (1988) 168:2091-2104. Barnett et al., "The Immune Response of BALB/C Mice of Influenza Hemagglutinin: Commonality of the B Cell and T Cell Repertoires and their Relevance to Antigenic Drift," EUR J IMMUNOL (1989) 19:515-521. Brady et al., "Differentiation of Salivary Agglutinin-Mediated Adherence and Aggregation of Mutans Streptococci by Use of Monoclonal Antibodies Against the Major Surface Adhesion P1," Infection And Immunity (1992) 60(3):1008-1017. Burgess et al., "Possible Dissociation of the Heparin-Binding and Mitogenic Activities of Heparin-Binding Activities by Site-Directed Mutagenesis of a Single Lysine Residue," J Cell Biol (1990) 111:2129-2138. Charles et al., "Identification and Characterization of a Protective Immunodominant B Cell Epitope of Pertactin (P.69) from Bordetella pertussis," Eur J Immunol (1991) 21:1147-1153. Emsly et al., "Structure of Bordetella pertussis Virulence Factor P.69 Pertactin," Nature (1986) 4381:90-92. Greenstein et al., "A Universal T Cell Epitope-Containing Peptide from Hepatitis B Surface Antigen Can Enhance Antibody Specific for HIV gp120," J Immunol (1992) 148:3970-3977. Jacobs et al., "Molecular Mimicry by Mycoplasma pneumoniae to Evade the Induction of Adherence Inhibiting Antibodies," J Med Microbiol (1995) 43:422-429. Kelly et al., "Genetic and Immunological Analysis of Conserved Epitopes of Antigen I/II in Oral Streptococci," J Dent Res (IADR Abstracts, Abstract 17) (1992) 71:517. Kelly et al., "T-Cell, Adhesion, and B-Cell Epitopes of the Cell Surface Streptococcus mutans Protein Antigen I/II," Infection and Immunity (1995) 63(9):3649-3658. Kendal et al. (Abstract 234), Todryk et al. (Abstract 235), Ma et al. (Abstract 238), J Dent Res (1994) 73(4):816. Lazar et al., "Transforming Growth Factor .alpha.: Mutation of Aspartic Acid 47 and Leucine 48 Results in Different Biological Activities," Mol Cell Biol (1988) 8(3):1247-1252. Lehner et al., "T-Cell and B-Cell Epitope Mapping and Construction of Peptide Vaccines," Molecular Pathogenesis of Periodontal Disease (Genco et al. ed., American Society for Microbiology 1994) Chapter 24:279-292. Moisset et al., "Conservation of Salivary Glycoprotein-Interacting and Human Immunoglobulin G-Cross-Reactive Domains of Antigen I/II in Oral Streptococci," Infection and Immunity (1994) 62(1):184-193. Munro et al., "A Protein Fragment of Streptococcal Cell Surface Antigen I/II which Prevents Adhesion of Streptococcus mutans," Infection and Immunity (1993) 61(11):4590-4598. Munro et al., "Mapping of Adhesion Epitopes of Streptococcal Antigen I/II," J Dent Res (IADR Abstracts, Abstract 1753) (1992) 71:735. Neurath et al., "Identification and Chemical Synthesis of a Host Cell Receptor Binding Site on Heptitis B Virus," Cell (1986) 46:429-436. Neutath et al., "Search for Hepatitis B. Virus Cell Receptors Reveals Binding Sites for Interleukin 6 on the Virus Envelope Protein," J Exp Med (1992) 4175:461-469. Salgaller et al., "Generation of Specific Anti-Melanoma Reactivity by Stimulation of Human Tumor-Infiltrating Lymphocytes with MAGE-1 Synthetic Peptide," Cancer Immunol Immunother (1994) 105-116. Sheriff et al., "Three Dimensional Structure of an Antibody-Antigen Complex," Proc Natl Acad Sci USA (1987) 84:8075-8079. Simitsek et al., "Modulation of Antigen Processing by Bound Antibodies Can Boost or Suppress Class II Major Histocompatibility Complex Presentation of Different T Cell Determinants," J Exp Med (1995) 4181:1957-1963. Smith-Gill et al., "Mapping the Antigenic Epitope for a Monoclonal Antibody Against Lysozyme," J Immunol (1982)125(1):314-322. Steward et al., "Specificity of Antibodies Reactive with Hepatitis B Surface Antigen Following Immunization with Synthetic Peptides," Vaccine (1993) 11:1405-1414. Todryk et al., "Induction of Immune Responses to Functional Determinants of a Cell Surface Streptococcal Antigen," Immunology (1996) 87:55-63. Watts et al., "Suppressive Effect of Antibody on Processing of T Cell Epitopes," J Exp Med (1993) 4178:1459-1463. |
| PATENT PARENT CASE TEXT | This data is not available for free |
| PATENT CLAIMS |
What is claimed is: 1. A polypeptide selected from the group consisting of: a) a first polypeptide consisting of i) a sequence of no more than 100 consecutive amino acids of SAI/II (SEQ. ID. NO: 23) which said sequence comprises the amino acid sequence of residues 1025-1044 of SAI/II (residues 2-21 of SEQ ID NO: 9) or residues 1024-1044 (SEQ. ID. NO: 9); or ii) modified amino acid sequence which differs from the sequence of i) by up to and including 8 amino acid alterations wherein said alterations consist of the substitution and/or deletion and/or insertion of up to and including 8 amino acids wherein the polypeptide containing said modified amino acid sequence has the same immunological and adhesion properties as the polypeptide of i); and b) a second polypeptide which is an extended form of said first polypeptide of i) or ii), which second polypeptide comprises said first polypeptide extended at the N-terminus or the C-terminus of said first polypeptide, or both, with non-wild-type amino acid sequence to form said second polypeptide; wherein non-wildtype amino acid sequence is defined as an amino acid sequence which does not natively occur at the N-terminus or C-terminus of said first polypeptide in SAI/II (SEQ. ID. NO: 23); and wherein said first polypeptide or second polypeptide may be in the N-terminal acylated and/or C-terminal amidated form. 2. A first polypeptide or a second polypeptide according to claim 1 wherein said first polypeptide is no more than 50 amino acids in length. 3. A first polypeptide or second polypeptide according to claim 1 wherein said first polypeptide is from 20 to 50 amino acids in length. 4. A first polypeptide or second polypeptide according to claim 1 wherein said first polypeptide is from 50 to 100 amino acids in length. 5. The first polypeptide or second polypeptide of claim 1 wherein the first polypeptide consists of 20-100 consecutive amino acids of SAI/II (SEQ. ID. NO: 23). 6. A pharmaceutical composition comprising the first polypeptide or second polypeptide of claim 1 in a pharmaceutically acceptable carrier. 7. A pharmaceutical composition comprising the first polypeptide or second polypeptide of claim 2 in a pharmaceutically acceptable carrier. 8. A pharmaceutical composition comprising the first polypeptide or second polypeptide of claim 3 in a pharmaceutically acceptable carrier. 9. A pharmaceutical composition comprising the first polypeptide or second polypeptide of claim 4 in a pharmaceutically acceptable carrier. 10. A pharmaceutical composition comprising the first polypeptide or second polypeptide of claim 5 in a pharmaceutically acceptable carrier. 11. The composition of claim 6 which is formulated for topical application in the mouth. 12. The composition of claim 7 which is formulated for topical application in the mouth. 13. The composition of claim 8 which is formulated for topical application in the mouth. 14. The composition of claim 9 which is formulated for topical application in the mouth. 15. The composition of claim 10 which is formulated for topical application in the mouth. 16. A method to vaccinate or treat a mammalian host against dental caries which method comprises administering to said host an effective amount of the first polypeptide or second polypeptide of claim 1. 17. A method to vaccinate or treat a mammalian host against dental caries which method comprises administering to said host an effective amount of the first polypeptide or second polypeptide of claim 2. 18. A method to vaccinate or treat a mammalian host against dental caries which method comprises administering to said host an effective amount of the first polypeptide or second polypeptide of claim 3. 19. A method to vaccinate or treat a mammalian host against dental caries which method comprises administering to said host an effective amount of the first polypeptide or second polypeptide of claim 4. 20. A method to vaccinate or treat a mammalian host against dental caries which method comprises administering to said host an effective amount of the first polypeptide or second polypeptide of claim 5. 21. The method of claim 16 wherein said polypeptide or polypeptide is administered by topical application in the mouth. 22. The method of claim 17 wherein said polypeptide or polypeptide is administered by topical application in the mouth. 23. The method of claim 18 wherein said polypeptide or polypeptide is administered by topical application in the mouth. 24. The method of claim 19 wherein said polypeptide or polypeptide is administered by topical application in the mouth. 25. The method of claim 20 wherein said first polypeptide or second polypeptide is administered by topical application in the mouth. |
| PATENT DESCRIPTION |
This invention relates to polypeptide fragments of the Streptococcus mutans I/II antigen that are useful in treating and preventing dental caries. Streptococcus mutans is the main etiological agent of dental caries, a disease which affects mammals including humans. The S. mutans I/II antigen (SA I/II) is a cell surface protein with an M.sub.r of about 185 kDa. It is believed to comprise several antigenic epitopes and to be at least partly responsible for S. mutans adhesion to teeth. SA I/II is described in British Patent No. 2,060,647, as are number antibodies to it. A putative 3.5 to 4.5 kDa fragment of SA I/II, "antigen X", has also been described in European Patent No. 0 116 472. However, it has now become clear that "antigen X" is not a fragment of SA I/II at all. Rather, it is a separate protein that merely co-purifies with SA I/II. It is believed to be encoded by a separate gene. Two large fragments of SA I/II, an N-terminal fragment (residues 39 to 481) and a 40 kDa central fragment (residues 816 to 1213) are recognised by human serum antibodies. Within the central fragment, 80% of the sera tested recognise elements within a proline-rich region (residues 839-955) that comprises three tandem repeats. This suggests that this region includes one or more B-cell epitopes. The central fragment (residues 816-1213) is also believed to comprise one or more adhesion sites that mediate S. mutans' attachment to the tooth. The aim of the above-mentioned work has been the development of vaccines for immunisation against dental caries. However, precise identification of the antigenic epitopes within SA I/II is a prerequisite for designing synthetic vaccines based on it. Similarly, precise identification of adhesion sites is essential for the design of drugs against dental caries that rely on inhibiting S. mutans' adhesion to the tooth. No antigenic epitopes (T-cell or B-cell epitopes) or adhesion sites within SA I/II have been characterised, nor has the precise location of any such regions been suggested. Also, there has been no indication of the location of S. mutans' T-cell epitopes as the above-mentioned work has concentrated on S. mutans' ability to adhere to teeth and to generate a B-cell response. The inventors have identified a number of T-cell epitopes, B-cell epitopes and adhesion sites within residues 803 to 1114 of SA I/II. Some of the T-cell and B-cell epitopes overlap or are contiguous with each other and/or with one or more of the adhesion sites. The presence of a number of antigenic epitopes of both types and a number of adhesion sites within the same region of SA I/II could not have been predicted and the finding that some of the adhesion sites and epitopes overlap or are contiguous with each other is particularly surprising. These findings make it possible to design effective synthetic vaccines against dental caries as well as drugs that engender resistance against the disease or alleviate pre-existing cases of it by preventing S. mutans' adhesion to the tooth. Further, the surprising finding that some of the T-antigenic epitopes and the adhesion site are contiguous or overlapping makes it possible to design bifunctional drugs that effect immunisation against dental caries as well as preventing adhesion of S. mutans to the tooth. Accordingly, the present invention provides a nucleic acid sequence which codes upon expression in a prokaryoic or eukaryotic host cell for a polypeptide product having one or more properties selected from (i) the ability to adhere to a mammalian tooth in a competitive manner with naturally occurring Streptococcus mutans antigen I/II, thus preventing or diminishing the adhesion of S.mutans to the tooth; (ii) the ability to stimulate a T-cell response; and (iii) the ability to stimulate a B-cell response, said nucleic acid sequence being selected from: (a) the sequences shown in SEQ. ID. Nos. 12 to 22 or the complementary strands thereof; (b) nucleic acid sequences having a length of not more than 1000 base pairs which hybridise to the sequences defined in (a) over at least 70% of their length; (c) nucleic acid sequences having a length of not more than 1000 base pairs which, but for the degeneracy of the genetic code, would hybridise to the nucleic acid sequences defined in (a) or (b) over at least 70% of their length and which sequences code for polypeptides having the same amino acid sequence code, would hybridise to the nucleic acid sequences defined in (a) or (b) over at least 70% of their length and which sequences code for polypeptides having the same amino acid sequence |
| PATENT EXAMPLES | This data is not available for free |
| PATENT PHOTOCOPY | Available on request |
|
Want more information ? Interested in the hidden information ? Click here and do your request. |