bstract
Murine monoclonal antibodies are prepared and characterized which bind selectively to human breast cancer cells, are IgGs or IgMs, and when conjugated to ricin A chain, exhibit a TCID 50% against at least one of MCF-7, CAMA-1, SKBR-3, or BT-20 cells of less than about 10 nM. Methods for diagnosing, monitoring, and treating human breast cancer with the antibodies or immunotoxins made therefrom are described.
Patent number: 4753894
Filing date: Jan 11, 1985
Issue date: Jun 28, 1988
Inventors: Arthur E. Frankel, David B. Ring, Michael J. Bjorn
Assignee: Cetus Corporation
What is claimed is:
1. A murine monoclonal antibody that:
- (a) binds selectively to human breast cancer cells;
- (b) has a G or M isotype;
- (c) when conjugated to ricin A chain, exhibits a TCID 50% of less than about 10 nM against at least one of MCF-7, CAMA-1, SKBR-3, or BT-20 cells; and
- (d) binds a human breast cancer antigen that is also bound by a reference antibody selected from the group consisting of 260F9, 113F1, 266B2, 454C11, 33F8, 317G5, 520C9, and 260F-9-1C9, as determined by immunoprecipitation or sandwich immunoassay.
2. The monoclonal antibody of claim 1 wherein said reference antibody is selected from the group consisting of 260F9, 266B2, 113F1, 454C11 and 317G5.
3. A murine x murine hybridoma cell line that produces the monoclonal antibody of claim 2.
4. An immunotoxin comprising a conjugate of (a) the monoclonal antibody of claim 2; and (b) a cytotoxic moiety.
5. The monoclonal antibody of claim 2, wherein said antibody is labeled with a detectable label.
6. A method of diagnosing whether a human cell is a breast cancer cell comprising
- (a) incubating a human cell with the antibody of claim 5; and
- (b) determining the presence of labeled binary immune complexes on the human cell.
7. A method of diagnosing whether a human cell is a breast cancer cell comprising:
- (a) incubating said human cell with the monoclonal antibody of claim 2;
- (b) incubating the human cell with a labeled antibody against said monoclonal antibody;
- (c) determining the presence of labeled ternary immune complexes on the human cell.
8. The monoclonal antibody of claim 1 wherein said reference antibody is 260F9 or 266B2.
9. The monoclonal antibody of claim 1 wherein said reference antibody is 454C11.
10. The monoclonal antibody of claim 9 wherein said antibody is labeled with a detectable label.
11. A method of diagnosing whether a human cell is a breast cancer cell comprising
- (a) incubating a human cell with the antibody of claim 10; and
- (b) determining the presence of labeled binary immune complexes on the human cell.
12. A method of diagnosing whether a human cell is a breast cancer cell comprising:
- (a) incubating said human cell with the monoclonal antibody of claim 9;
- (b) incubating the human cell with a labeled antibody against said monoclonal antibody;
- (c) determining the presence of labeled ternary immune complexes on the human cell.
13. The monoclonal antibody of claim 1 wherein said reference antibody is 317G5.
14. The monoclonal antibody of claim 1 wherein said reference antibody is 113F1.
15. The monoclonal antibody of claim 1 wherein said reference antibody is 33F8.
16. The monoclonal antibody of claim 1 that binds the same epitope as the reference antibody.
17. The monoclonal antibody of claim 1 that is 260F9.
18. The cell line of claim 17 selected from the group consisting of 260F9, 113F1, 266B2, 454C11, 33F8, 317G5, 520C9, and 260F91C9.
19. The monoclonal antibody of claim 1 that is 260F9-1C9.
20. The monoclonal antibody of claim 1 wherein the exhibited TCID 50% is less than about 1 nM.
21. A murine x murine hybridoma cell line that produces the monoclonal antibody of claim 1.
22. An immunotoxin comprising a conjugate of
- (a) the monoclonal antibody of claim 1 and
- (b) a cytotoxic moiety.
23. The immunotoxin of claim 22 wherein the cytotoxic moiety is ricin A chain, PAPII, abrin A chain or a nonbinding, active fragment of diphtheria toxin.
24. A method of killing human breast cancer cells comprising contacting said cells with a cytocidally effective amount of the immunotoxin of claim 23.
25. The immunotoxin of claim 22 wherein the cytotoxic moiety is ricin A chain.
26. A method of killing human breast cancer cells comprising contacting said cells with a cytocidally effective amount of the immunotoxin of claim 22.
27. The monoclonal antibody of claim 1 wherein said antibody is labeled with a detectable label.
28. A method of diagnosing whether a human cell is a breast cancer cell comprising
- (a) incubating a human cell with the antibody of claim 27 and
- (b) determining the presence of labeled binary immune complexes on the human cell.
29. A method of diagnosing whether a human cell is a breast cancer cell comprising:
- (a) incubating said human cell with the monoclonal antibody of claim 1;
- (b) incubating the human cell with a labeled antibody against said monoclonal antibody;
- (c) determining the presence of labeled ternary immune complexes on the human cell.