IgA-binding peptide and purification of IgA using the same

Patent metadata

Field	Value
Publication number	US-9593147-B2
Application number	US-201113699579-A
Country	US
Kind code	B2
Filing date	May 24, 2011
Priority date	May 24, 2010
Publication date	Mar 14, 2017
Grant date	Mar 14, 2017

Abstract

This invention relates to: a peptide which comprises an amino acid sequence consisting of 12 to 18 amino acid residues represented by (X 1-3 )—C—(X 8-10 )—C—(X 1-3 ) wherein each X independently represents an arbitrary amino acid residue other than cysteine, and C represents a cysteine residue, and is capable of binding to human IgA; and to a method for analyzing or purifying human IgA using the peptide.

First claim

The invention claimed is:

1. A peptide which consists of any of the following amino acid sequences 1) to 7):
1) QMRCLSYKGRRVCLWL (SEQ ID NO: 2),
2) KRLCLQYKGSKVCFRL (SEQ ID NO: 4),
3) RMRCLTYRGRRVCLEL (SEQ ID NO: 5),
4) SMRCLQYRGSRVCLTL (SEQ ID NO: 6),
5) HLRCLRYKGTRVCFSL (SEQ ID NO: 8),
6) HVRCLSYKGREVCVQL (SEQ ID NO: 9), and
7) PRMCLHYKGRRVCIPY (SEQ ID NO: 10),

wherein the peptide is capable of binding to human IgA, and
wherein said peptide is optionally labeled, linked to a protein as part of a fusion protein, or bound to a solid phase.

2. The peptide according to claim 1 , wherein the peptide has a disulfide bond between its two cysteine (C) residues.

3. The peptide according to claim 1 , wherein the peptide is capable of binding to serum (monomeric) IgA and secretory (dimeric) IgA.

4. The peptide according to claim 1 , wherein the peptide is labeled.

5. A fusion protein comprising a protein linked to a peptide according to claim 1 .

6. An immobilized peptide comprising a peptide according to claim 1 bound to a solid phase.

7. A nucleic acid encoding a peptide according to claim 1 .

8. A method for purifying IgA comprising binding IgA to
A) a peptide which consists of any of the following amino acid sequences 1) to 7):
1) QMRCLSYKGRRVCLWL (SEQ ID NO: 2),
2) KRLCLQYKGSKVCFRL (SEQ ID NO: 4),
3) RMRCLTYRGRRVCLEL (SEQ ID NO: 5),
4) SMRCLQYRGSRVCLTL (SEQ ID NO: 6),
5) HLRCLRYKGTRVCFSL (SEQ ID NO: 8),
6) HVRCLSYKGREVCVQL (SEQ ID NO: 9), and
7) PRMCLHYKGRRVCIPY (SEQ ID NO: 10),

wherein the peptide is capable of binding to human IgA, or
(B) an immobilized peptide according to claim 6 ; and
releasing the bound IgA to collect the purified IgA.

9. A method for detecting IgA comprising binding IgA in a sample to
A) a peptide that consists of any of the following amino acid sequences 1) to 7):
1) QMRCLSYKGRRVCLWL (SEQ ID NO: 2),
2) KRLCLQYKGSKVCFRL (SEQ ID NO: 4),
3) RMRCLTYRGRRVCLEL (SEQ ID NO: 5),
4) SMRCLQYRGSRVCLTL (SEQ ID NO: 6),
5) HLRCLRYKGTRVCFSL (SEQ ID NO: 8),
6) HVRCLSYKGREVCVQL (SEQ ID NO: 9), and
7) PRMCLHYKGRRVCIPY (SEQ ID NO: 10),

wherein the peptide is capable of binding to human IgA, or
(B) an immobilized peptide according to claim 6 ; and
detecting bound IgA.

10. A kit for analysis or purification of human IgA comprising
(A) at least one peptide that consists of any of the following amino acid sequences 1) to 7):
1) QMRCLSYKGRRVCLWL (SEQ ID NO: 2),
2) KRLCLQYKGSKVCFRL (SEQ ID NO: 4),
3) RMRCLTYRGRRVCLEL (SEQ ID NO: 5),
4) SMRCLQYRGSRVCLTL (SEQ ID NO: 6),
5) HLRCLRYKGTRVCFSL (HQ ID NO: 8),
6) HVRCLSYKGREVCVQL (HQ ID NO: 9), and
7) PRMCLHYKGRRVCIPY (HQ ID NO: 10),

wherein the peptide is capable of binding to human IgA, or
(B) an immobilized peptide according to claim 6 .

11. A column for IgA separation, comprising an immobilized peptide according to claim 6 .

12. A peptide consisting of any of the following amino acid sequences 1) to 7):
1) QMRCLSYKGRRVCLWL (SEQ ID NO: 2),
2) KRLCLQYKGSKVCFRL (SEQ ID NO: 4),
3) RMRCLTYRGRRVCLEL (SEQ ID NO: 5),
4) SMRCLQYRGSRVCLTL (SEQ ID NO: 6),
5) HLRCLRYKGTRVCFSL (SEQ ID NO: 8),
6) HVRCLSYKGREVCVQL (SEQ ID NO: 9), and
7) PRMCLHYKGRRVCIPY (SEQ ID NO: 10),

wherein the peptide is capable of binding to human IgA.

Assignees

• Ito Yuji
• Univ Kagoshima
• Otsuka Chemical Co Ltd

Inventors

• Ito Yuji

Classifications

• G01N2030/8831

  involving peptides or proteins · CPC title

• C07K2317/21

  from primates, e.g. man · CPC title

• C07K16/065

  Purification, fragmentation · CPC title

• B01D15/3809

  of the antigen-antibody type, e.g. protein A, G or L chromatography · CPC title

• G01N33/6854

  Immunoglobulins · CPC title