Modified carboxypeptidase enzymes and their use
AssigneeCancer Research Technology Limited
InventorsRichard H. J. Begent, Kerry Chester, Nigel P. Minton, Anthony R. Rees, Surinder K. Sharma, Daniel I. R. Spencer
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Abstract
The invention relates to improvements relating to cancer therapy based on the identification of a number of regions of CPG2 which contain epitopes which appear to be involved in the production of a host immune response and which may be modified to alter the immunogenicity in patients. Production of fusions of CPG2 with an antibody, where the CPG2 protein has been tagged provides a CPG2 protein which has reduced immunogenicity. By using partially glycosylated enzyme obtainable by P. pastoris expression, the efficacy of antibody-CPG2 fusions is enhanced.
Claims10
An isolated carboxypeptidase enzyme, CPG2, in which an immunogenic region is modified to reduce immunogenicity to a mammalian immune system whilst retaining CPG2 activity, wherein the immunogenic region is selected from the group consisting of:
- (i) KIKGRGGK (SEQ ID NO:1) comprising residues 98-105 of SEQ ID NO:7, (ii) KEYGVRD (SEQ ID NO:2) comprising residues 157-163 of SEQ ID NO:7, (iii) YGVRD (SEQ ID NO:6) comprising residues 159-163 of SEQ ID NO:7, (iv) KLADY (SEQ ID NO:3), comprising residues 191-195 of SEQ ID NO:7, (v) GAGK (SEQ ID NO:4), comprising residues 412 to the C-terminal residue 415 of SEQ ID NO:7, (vi) AG comprising residues 413-414 of SEQ ID NO:7, and (vii) EGGKKLVDK (SEQ ID NO:5) comprising residues 331-339 of SEQ ID NO:7, wherein said enzyme is fused to an anti-CEA antibody.
An isolated or purified Pseudomonas carboxypeptidase CPG2 enzyme wherein the C-terminus of the enzyme comprises an extension selected from the group consisting of a histidine tag, a myc tag, and a myc-his tag and wherein said CPG2 enzyme is fused to an anti-CEA antibody.
An isolated carboxypeptidase enzyme, CPG2, in which an immunogenic region is modified to reduce immunogenicity to a mammalian immune system whilst retaining CPG2 activity, wherein the immunogenic region is selected from the group consisting of:
- KIKGRGGK (SEQ ID NO:1) comprising residues 98-105 of SEQ ID NO:7);
- (ii) KEYGVRD (SEQ ID NO:2) comprising residues 157-163 of SEQ ID NO:7;
- (iii) YGVRD (SEQ ID NO:6) comprising residues 159-163 of SEQ ID NO:7;
- (iv) KLADY (SEQ ID NO:3) comprising residues 191-195 of SEQ ID NO:7;
- (v) GAGK (SEQ ID NO:4) comprising residues 412 to the C-terminal residue 415 of SEQ ID NO:7;
- (vi) AG comprising residues 413-414 of SEQ ID NO:7;
- and
- (vii) EGGKKLVDK (SEQ ID NO:5) comprising residues 331-339 of SEQ ID NO:7;
- wherein said enzyme is fused to an anti-CEA antibody;
- and wherein the C-terminus of the enzyme comprises an extension selected from the group consisting of a histidine tag, a myc tag and a myc-his tag.
Dependencies are inferred from the claim text.