Specific detection tool for mesenchymal and epithelial-mesenchymal transformed circulating tumor cells
The present invention includes the discovery of cell-surface vimentin as a novel biomarker to detect and isolate mesenchymal and epithelial-mesenchymal transformed circulating tumor cells from blood of cancer patients. In addition, an antibody specific for the detection of cell-surface vimentin on circulating tumor cells and the use the antibody to detect, enumerate, and isolate CTC are provided.
1. An isolated antibody-cell complex comprising an isolated and captured complex of a monoclonal antibody or an antigen binding fragment thereof bound to vimentin on the cell surface of a non-permeabilized metastatic tumor cell, wherein the metastatic tumor cell is a circulating metastatic tumor cell of a solid tumor, wherein the antibody or antigen binding fragment comprises:
(a) a first VH CDR identical to SEQ ID NO: 3;
(b) a second VH CDR identical to SEQ ID NO: 4;
(c) a third VH CDR identical to SEQ ID NO: 5;
(d) a first VL CDR identical to SEQ ID NO: 6;
(e) a second VL CDR identical to SEQ ID NO: 7; and
(f) a third VL CDR identical to SEQ ID NO: 8.
2. The complex of claim 1 , wherein the antibody or antigen binding fragment comprises a V H domain at least 95% identical to the V H domain of 84-1 (SEQ ID NO: 1) and a V L domain at least 95% identical to the V L domain of 84-1 (SEQ ID NO: 2).
3. The complex of claim 1 , wherein the antibody or antigen binding fragment comprises a V H domain identical to the V H domain of 84-1 (SEQ ID NO: 1) and a V L domain identical to the V L domain of 84-1 (SEQ ID NO: 2).
4. The complex of claim 1 , in a composition further comprising a protein tyrosine phosphatase inhibitor to stabilize the complex.
5. The complex of claim 4 , wherein the protein tyrosine phosphatase inhibitor is sodium orthovanadate, dephostatin, mpV(pic), phenylarsine oxide, sodium stibogluconate, BAY U6751, a tyrosine phosphatase inhibitor cocktail (including sodium vanadate, sodium molybdate, sodium tartrate, and imidazole), and RK-682.
6. The complex of claim 1 , wherein the tumor cell is an epithelial tumor or a mesenchymal tumor.
7. The complex of claim 1 , bound to a surface.
8. The complex of claim 7 , wherein the surface is the surface of test tube, a microtiter well, a slide or a chip.
9. The complex of claim 7 , in a composition further comprising an enzyme and a substrate for the enzyme.
10. The complex of claim 9 , wherein the enzyme is horseradish peroxidase (HRP) or alkaline phosphatase (AP).
11. The complex of claim 1 , wherein a reporter or effector molecule is bound to the complex.
12. The complex of claim 9 , wherein the substrate is 3,3′,5,5′-Tetramethylbenzidine or 3,3′-Diaminobenzidine.
13. The complex of claim 1 , wherein the antigen binding fragment is an Fab′, a F(ab′)2, a F(ab′) 3, a monovalent scFv, or a bivalent scFV.
14. The complex of claim 9 , wherein the substrate is 3,3′,5,5′-Tetramethylbenzidine or 3,3′-Diaminobenzidine.
15. The antibody-cell complex of claim 1 , wherein the complex is formed ex vivo or in vitro.
16. The complex of claim 11 , wherein the reporter or effector molecule is an enzyme, a florescence-linked CSV binding antibody, or an anti-mouse IgG-linked enzyme.