Drug – bio-affecting and body treating compositions – Immunoglobulin – antiserum – antibody – or antibody fragment,... – Monoclonal antibody or fragment thereof
Reexamination Certificate
1995-06-07
2001-04-17
Johnson, Nancy A. (Department: 1642)
Drug, bio-affecting and body treating compositions
Immunoglobulin, antiserum, antibody, or antibody fragment,...
Monoclonal antibody or fragment thereof
C424S130100, C424S138100, C424S141100, C424S152100, C424S155100, C424S156100, C530S388100, C530S388200, C530S388220, C530S388800, C530S388850
Reexamination Certificate
active
06217866
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to new hybrid cell lines and in particular to hybrid cell lines for production of monoclonal antibodies specific to a human receptor for epidermal growth factor (EGF) which can inhibit the growth of human tumor cells that express human EGF receptors, to the antibodies so produced, to therapeutic methods employing the antibodies, and to therapeutic methods employing the antibodies in combination with anti-neoplastic agents.
Control of cell growth is regulated by the interaction of soluble growth factors and cell membrane receptors.
The first step in the mitogenic stimulation of epidermal cells is the specific binding of epidermal growth factor (EGF) to a membrane glycoprotein known as the epidermal growth factor receptor (EGF receptor). (Carpenter, et al., Epidermal Growth Factor,
Annual Review Biochem.,
Vol. 48, 193-216 (1979)). The EGF receptor is composed of 1,186 amino acids which are divided into an extracellular portion of 621 residues and a cytoplasmic portion of 542 residues connected by a single hydrophobic transmembrane segment of 23 residues. (Ullrich et al., Human Epidermal Growth Factor cDNA Sequence and Aberrant Expression of the Amplified Gene in A-431 Epidermoid Carcinoma Cells,
Nature,
Vol. 309, 418-25 (1986)). The external portion of the EGF receptor can be subdivided into four domains. Recently, it has been demonstrated that domain III, residues 333 to 460, which is flanked by two cysteine domains is likely to contain the EGF binding site of the receptor. (Lax, et al., Localization of a Major Receptor-Binding Domain for Epidermal Growth Factor by Affinity Labeling,
Mol. and Cell Biol.,
Vol. 8, 1831-1834 (1988)). The binding of EGF to domain III leads to the initiation of pleiotropic responses leading to DNA synthesis and cell proliferation.
It has been found in various types of human tumor cells that those cells overexpress EGF receptors. For example, the cancerous cells of bladder tumors have been shown to have a relatively large population of EGF receptors. (Neal et al., Epidermal Growth Factor Receptor in Human Bladder Cancer: Comparison of Invasive and Superficial Tumors,
Lancet,
Vol. 1, 366-367 (1985)). Breast cancer cells exhibit a positive correlation between EGF receptor density and tumor size and a negative correlation with the extent of differentiation. (Sainsbury et al., Epidermal Growth Factor Receptors and Oestrogen Receptors in Human Breast Cancer.
Lancet,
Vol. 1, 364-366 (1985); Presence of Epidermal Growth Factor Receptor as an Indicator of Poor Prognosis In Patients With Breast Cancer.
J. Clin. Path.,
Vol. 38, 1225-1228; Epidermal-Growth-Factor Receptor Status as Predictor of Early Recurrence and Death From Breast Cancer.
Lancet,
Vol.1, 1398-1400 (1987). The tumorigenicity of a series of human vulval epidermoid carcinoma (A431) clonal variants implanted into athymic mice having different levels of EGF receptors was found to correlate directly with the level of expression of the EGY receptor (Santon et al., Effects of Epidermal Growth Factor Receptor Concentration on Tumorigenicity of A431 cells in nude mice.
Cancer Res.,
Vol. 46, 4701-4700 (1986)). Thus, it has been proposed that overexpression of EGF receptors play a role in the origin or tumorigenesis of cancer cells.
The influence of EGF receptor density on the biological behavior of cancer cells may be mediated by the interaction of the receptor with its ligands—namely, EGF or transforming growth factor (TGF). In the majority of cells, when EGF binds to a specific region of the EGF receptor, the cell is mitogenically stimulated. Other tumor cells, such as A431 cells are not mitogenically stimulated by the binding of EGF to its receptors.
Two groups have reported in vivo growth inhibition of tumor A431 cell xenografts in nude mice by binding monoclonal antibodies to the epidermal growth factor receptor of the tumorous cells. Masui et al. demonstrated that treatment with anti-EGF receptor monoclonal antibodies of the IgG2a and IgGI isotype completely prevented tumor formation in athymic mice by subcutaneously implanted A431 cells when treatment was started on the day of tumor cell inoculation. (Masui et al., Growth Inhibition of Human Tumor Cells in Athymic Mice by Anti Epidermal Growth Factor Receptor Monoclonal Antibodies.
Cancer Res.,
Vol. 44 1002-1007 (1984); Mechanism of Antitumor Activity in Mice for Anti Epidermal Growth Factor Receptor Monoclonal Antibodies With Different Isotypes.
Cancer Res.
Vol. 46 5592-5598 (1986)). Rodeck et al. used a different monoclonal antibody than Masui of the IgG2a isotype which also binds to the EGF receptor of A431 cells to completely inhibit tumor growth of A431 cells xenotransplanted in mice. (Rodeck et al. Tumor Growth Modulation by a Monoclonal Antibody to the Epidermal Growth Factor Receptor: Immunologically Mediated and Effector Cell—Independent Effects.
Cancer Res.,
Vol. 47, 3692-3696 (1987)).
To date, no one, however, has inhibited the in vitro or in vivo growth of human oral epidermoid carcinoma (KB) or human mammary epithelial (184AIN4 and 184AIN4-T—collectively “184”) cells. KB and 184 cells are commonly used in studies relating to the EGF-receptor.
KB and 184 cells are substantially different from A431 cells, especially in terms of their growth response to epidermal growth factor. KB and 184 cells are growth stimulated by high concentrations of epidermal growth factor whereas A431 cells are growth inhibited by high concentrations of epidermal growth factor.
Those differences as well as the lack of complete understanding of the mechanism by which the anti-EGF-receptor antibodies inhibit the growth of tumor cells in vivo, prohibit one from accurately determining whether monoclonal antibodies which bind to EGF receptor of A431 cells and demonstrate anti-tumoral activity on A431 cell xenografts in nude mice will also demonstrate antitumoral activity on KB or 184 cell xenografts in nude mice.
Additionally, because human tumor cells are also growth stimulated by epidermal growth factor, KB and 184 cells provide a more representative pattern of responding to EGF than A431 cells, and, in fact, are used as a model for human tumor cells expressing EGF receptors. (Willington et al.
J Cell Biol.,
Vol. 94, 207-212 (1982).
The primary goal in treating tumors is to kill all the cells of the tumor. A therapeutic agent that kills the cell is defined as cytotoxic. A therapeutic agent that merely prevents the cells from replicating, rather than killing the cells, is defined as cytostatic.
Treatment solely with monoclonal antibodies which bind to the EGF receptor merely prevent the cells from replicating, and thus, the monoclonal antibodies act as a cytostatic agent. In order to overcome the monoclonal antibody's cytostatic limitations, monoclonal antibodies specific to the extracellular domain of human epidermal growth factor receptors have been combined with macrophage or mouse complement to yield a cytotoxic response against A431 cells. (Masui et al., Mechanism of Antitumor Activity in Mice for Anti-Epidermal Growth Factor Receptor Monoclonal Antibodies with Different Isotopes,
Cancer Research,
Vol. 46, 5592-5598 (1986)).
Anti-neoplastic or chemotheropeutic agents administered by themselves, are effective cytotoxic agents. The use of anti-neoplastic agents such as doxorubicin (adriamycin) and cisplatin, for example, are well known in the art. Use of those reagents by themselves, however, are only effective at levels which are toxic or subtoxic to the patient. Cisplatin is intravenously administered as a 100 mg/m
2
dose once every four weeks and adriamycin is intravenously administered as a 60-75 mg/m
2
dose one every 21 days.
Bacterial Expression of Antibodies: The prototypical immunoglobulin structure consists of a 150,000 dalton heterodimer composed of two heavy (50,000 daltons each) and two light (25,000 daltons each) chains. Each heavy and light chain pair are covalently attached by a disulfide bond located between the first and second constant domains that joins the ca
Bellot Francoise
Cheadle Christopher
Givol David
Kris Richard
Ricca George A.
Feit Irving N.
Hoffmann & Baron , LLP
Johnson Nancy A.
Rhone-Poulenc Rorer International (Holdings) Inc.
LandOfFree
Monoclonal antibodies specific to human epidermal growth... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Monoclonal antibodies specific to human epidermal growth..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Monoclonal antibodies specific to human epidermal growth... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2517381