GKN1 (gastrokine 1) specific antibody, and use thereof
View Patent ↗The present invention relates to a novel antibody specifically binding to a specific epitope of GKN1 (gastrokine 1) protein, and a gastric cancer diagnostic use thereof. An antibody specific to GKN1 according to the present invention specifically binds to a new epitope, and can be used to confirm the level of GKN1 protein in serum and thereby detect (diagnose) gastric cancer with 100% sensitivity and specificity. Thus, the antibody can be useful for screening and diagnosing gastric cancer.
1 . An isolated antibody specifically binding to a single epitope located in a BRICHOS domain of gastrokine 1 (GKN1) protein or an immunologically active fragment thereof, comprising:
a light chain variable domain (VL) including a complementarity determining region light chain (CDRL) 1 including the amino acid sequence represented by SEQ ID NO: 2, a CDRL2 including the amino acid sequence represented by SEQ ID NO: 3, and a CDRL3 including the amino acid sequence represented by SEQ ID NO: 4; and
a heavy chain variable domain (VH) including a complementarity determining region heavy chain (CDRH) 1 including the amino acid sequence represented by SEQ ID NO: 5, a CDRH2 including the amino acid sequence represented by SEQ ID NO: 6, and a CDRH3 including the amino acid sequence represented by SEQ ID NO: 7.
2 . The isolated antibody or the immunologically active fragment thereof of claim 1 , wherein the epitope includes an amino acid sequence represented by SEQ ID NO: 1.
3 . The isolated antibody or the immunologically active fragment thereof of claim 1 , comprising: a VL domain including framework region (FR) 1 including the amino acid sequence represented by SEQ ID NO: 8, FR2 including the amino acid sequence represented by SEQ ID NO: 9, FR3 including the amino acid sequence represented by SEQ ID NO: 10, and FR4 including the amino acid sequence represented by SEQ ID NO: 11.
4 . The isolated antibody or the immunologically active fragment thereof of claim 1 , comprising: a VH domain including framework region (FR) 1 including the amino acid sequence represented by SEQ ID NO: 12, FR2 including the amino acid sequence represented by SEQ ID NO: 13, FR3 including the amino acid sequence represented by SEQ ID NO: 14, and FR4 including the amino acid sequence represented by SEQ ID NO: 15.
5 . The isolated antibody or the immunologically active fragment thereof of claim 1 , comprising a VL domain including the amino acid sequence represented by SEQ ID NO: 16.
6 . The isolated antibody or the immunologically active fragment thereof of claim 1 , comprising a VH domain including the amino acid sequence represented by SEQ ID NO: 17.
7 . The isolated antibody or the immunologically active fragment thereof of claim 1 , comprising the amino acid sequence represented by SEQ ID NO: 18.
8 . A composition for screening and diagnosing gastric cancer comprising the isolated antibody or the immunologically active fragment thereof of claim 1 .
9 . A kit for screening and diagnosing gastric cancer comprising the composition of claim 8 .
10 . An isolated nucleic acid molecule encoding the isolated antibody or the immunologically active fragment thereof of claim 1 .
11 . The isolated nucleic acid molecule of claim 10 , comprising any one selected from the group consisting of nucleotide sequences represented by SEQ ID NOs: 19 to 35.
12 . A vector comprising the isolated nucleic acid molecule of claim 10 .
13 . A host cell transformed with the vector of claim 12 .
14 . A method for producing an antibody specific to GKN1 or an immunologically active fragment thereof comprising: a) culturing a host cell transformed with a vector including an isolated nucleic acid molecule encoding the isolated antibody or the immunologically active fragment thereof of claim 1 ; and
b) recovering the antibody or the immunologically active fragment thereof from the host cell culture.