Claims
- 1. A non-naturally occurring variant of a C-terminal fragment of a Plasmodium merozoite surface protein-1 (MSP-1) wherein said variant has (i) a reduced affinity, compared with a naturally occurring Plasmodium MSP-119, for at least one first antibody capable of blocking the binding of a second antibody, which second antibody inhibits the proteolytic cleavage of Plasmodium MSP-142 and (ii) substantially the same affinity for at least one third antibody compared with said naturally occurring Plasmodium MSP-119. which third antibody inhibits the proteolytic cleavage of Plasmodium MSP-142.
- 2. A variant according to claim 1 wherein said Plasmodium MSP-119 and MSP-142 are Plasmodium falciparum MSP-119 and MSP-142.
- 3. A variant according to claim 1 wherein the first antibody is selected from mAbs 1E1, 2.2, 7.5, 9C8 and 111.4.
- 4. A variant according to claim 1 wherein the second and/or third antibody is selected from mAbs 12.8, 12.10 and 5B1.
- 5. A non-naturally occurring variant of a C-terminal fragment of a Plasmodium merozoite surface protein-1 (MSP-1) comprising an amino acid modification at any one of amino acid residues 14, 15, 27, 31, 34, 43, 48 and 53 of the Plasmodium falciparum MSP-1 19 amino acid sequence shown as SEQ I.D. No. 1 or their equivalent positions in other Plasmodium MSP-119 polypeptides.
- 6. A variant according to claim 5 wherein said modifications are selected from Gln14→Arg, Gln14→Gly, Asn15→Arg, Glu27→Tyr, Leu31→Arg, Tyr34→Ser, Tyr34→Ile, Glu43→Leu, Thr48→Lys and Asn53→Arg and their equivalents in other Plasmodium MSP-119 polypeptides.
- 7. A variant according to claim 6 wherein said substitutions are selected from [Glu27→Tyr, Leu31→Arg and Glu43→Leu], [Glu27→Tyr, Leu31→Arg, Tyr34→Ser and Glu43→Leu], [Asn15→Arg, Glu27→Tyr, Leu31→Arg and Glu43→Leu] and their equivalents in other Plasmodium MSP-119 polypeptides.
- 8. A variant according to claim 1 comprising a mutation at Cys12 and/or Cys28 of the Plasmodium falciparum MSP-119 amino acid sequence shown as SEQ I.D. No. 1.
- 9. A variant according to claim 8 in which the mutation is a substitution selected from Cys12□Ile and Cys28□Trp, and Cys12□Ala and Cys28□Phe.
- 10. A variant according to claim 8 in which the mutation is the deletion of Cys12 and/or Cys28 of the Plasmodium falciparum MSP-119 amino acid sequence shown as SEQ ID No. 1.
- 11. A variant according to claim 9, in which the substitutions are selected from [Cys 12□Ile, Asn 15□Arg, Glu27□Tyr, Cys28□Trp, Leu31□Arg, Glu43→Leu], [Cys12□Ile, Asn 15□Arg, Glu27□Tyr, Cys28□Trp, Leu31□Arg, Glu43□Leu, Asn53□Arg], [Cys12□Ile, Asn 15□Arg, Glu27□Tyr, Cys28□Trp, Leu31□Arg, Tyr34□Ser, Glu43□Leu, Asn53□Arg] and their equivalents in other PlasmodiumMSP-119 polypeptides.
- 12. A method for producing a Plasmodium MSP-1 variant for use in preparing a vaccine composition which method comprises modifying one or more amino acid residues of a Plasmodium MSP-1 C-terminal fragment such that the resulting derivative has (i) a reduced affinity, compared with a naturally occurring Plasmodium MSP-119, for at least one first antibody capable of blocking the binding of a second antibody, which second antibody inhibits the proteolytic cleavage of Plasmodium MSP-142 and (ii) substantially the same affinity for at least one third antibody compared with said naturally occurring Plasmodium MSP-119, which third antibody inhibits the proteolytic cleavage of Plasmodium MSP-142.
- 13. A non-naturally occurring Plasmodium MSP-1 variant obtained by the method of claim 12.
- 14. A polynucleotide encoding a variant according to claim 1 or 5 operably linked to a regulatory sequence capable of directing the expression of said nucleotide in a host cell.
- 15. A polynucleotide according to claim 14 having a sequence optimised for expression in said host cell.
- 16. A polynucleotide according to claim 14, in which the host cell is a Pichia pastoris cell.
- 17. A nucleic acid vector comprising a polynucleotide according to claim 14.
- 18. A host cell comprising a vector according to claim 17.
- 19. A pharmaceutical composition comprising a variant according to claim 1 together with a pharmaceutically acceptable carrier or diluent.
- 20. A composition according to claim 19 further comprising an immunogenic Plasmodium polypeptide or fragment or derivative thereof.
- 21. A method for producing anti-MSP-l antibodies which method comprises administering a polypeptide according to claim 1 to a mammal.
- 22. A method for producing polyclonal anti-MSP-1 antibodies which method comprises administering a polypeptide according to claim 1 to a mammal and extracting the serum from said mammal.
- 23. An antibody produced by the method of claim 21.
- 24. A method of inducing immunity against malaria induced by Plasmodium falciparum which comprises administering to a person in need of such immunity an effective amount of the variant of claim 1.
- 25. A method of immunizing a mammal, said method comprising administering an effective amount the polypeptide of claim 1.
- 26. The method of claim 25, wherein said mammal is immunized against malaria.
- 27. A method of treating a malaria infection in a human patient which comprises administering to the patient an effective amount of the pharmaceutical composition of claim 19.
- 28. A computer readable medium having stored thereon a model of the MSP-119 NMR structure.
- 29. A nucleic acid encoding a Plasmodium MSP-1 polypeptide, in which the nucleic acid is optimised for expression in a heterologous host cell.
- 30. A nucleic acid according to claim 29, in which the heterologous host is a Pischia pastoris cell.
- 31. A nucleic acid according to claim 29, in which the polypeptide is selected from an MSP-142 polypeptide comprising a sequence shown in FIGS. 15C and 15E an MSP-119 polypeptide comprising a sequence shown in FIG. 15C, and an MSP-133 polypeptide comprising a sequence shown in FIG. 15E.
- 32. A nucleic acid according to claim 29, in which the nucleic acid comprises a sequence selected from the sequences of FIG. 15A, FIG. 15B and FIG. 15D.
- 33. A nucleic acid vector comprising a nucleic acid according to claim 29.
- 34. A host cell comprising a vector according to claim 33.
- 35. A pharmaceutical composition comprising a nucleic acid according to claim 29 together with a pharmaceutically acceptable carrier or diluent.
- 36. A composition according to claim 35 further comprising an immunogenic Plasmodium polypeptide or fragment or derivative thereof.
Priority Claims (2)
Number |
Date |
Country |
Kind |
GB9909072.2 |
Apr 1999 |
GB |
|
CA2271451 |
May 1999 |
CA |
|
PRIORITY
[0001] This application is a continuation of application serial number PCT/GB00/01558, filed Apr. 20, 2000, which claims priority to application numbers GB9909072.2, filed Apr. 20, 1999, U.S. Ser. No. 09/311,817, filed May 13, 1999, and CA2,271,451, filed May 25, 1999, all of which are incorporated herein by reference in their entirety.
Continuations (1)
|
Number |
Date |
Country |
Parent |
PCT/GB00/01558 |
Apr 2000 |
US |
Child |
09978756 |
Oct 2001 |
US |