Binding parameters of monoclonal antibodies reacting with ovarian carcinoma ascites cells

Abstract

Binding parameters were determined for four mouse monoclonal antibodies reacting with three antigens on the surface of fresh human ovarian carcinoma ascites cells, under nearly physiological conditions. The object of these experiments was to aid in the selection of the optimal monoclonal antibodies for intraperitoneal immunotherapy. The number of antigenic sites per cell, the effective equilibrium association constant (affinity) and the half-life for dissociation were: for Ab MH99, 1.2 x 10(6) sites/cell, (1.9-4.1) x 10(8) M-1, and 4 h; for Ab MX35, (3.2-4.1) x 10(5) sites/cell, (3.4-4.8) x 10(8) M-1, and greater than 10 h; and for Ab MW207, 1.3 x 10(5) sites/cell, (3.6-4.1) x 10(9) M-1, and 3.1 h, respectively. One of the antigens, MH99, is recognized by five different monoclonal antibodies, and competitive inhibition experiments demonstrated that two distinct determinants are present; this antigen is also recognized by the previously described Ab 17-1A. These binding data will aid the rational design of immunotherapy strategies.

Rebmab200, a Humanized Monoclonal Antibody Targeting the Sodium Phosphate Transporter NaPi2b Displays Strong Immune Mediated Cytotoxicity against Cancer: A Novel Reagent for Targeted Antibody Therapy of Cancer

“…While MX35 presented a half-life for dissociation greater than 10 h [26], Rebmab200 forms a similar complex with the epitope as shown by its slightly lower equilibrium dissociation constant.…”

Molecular Identification of a Human Carcinoma‐associated Glycoprotein Antigen Recognized by Mouse Monoclonal Antibody FU‐MK‐1

“…31,32) Antibodies MJ37 and MP75 31,32) are directed against the same epitope, and RS11-51, 33) GA733, 11) and 17-1A 4) are all directed against another epitope. Antibodies MH99, 31,34) KS1/4, 8) AUAI, 35) MM121, 31,32) and Trop-1 6) block the binding of both groups of antibodies, indicating that the antigenic structure recognized by these antibodies partially overlaps both of the epitopes detected by the other groups of anti-GA733-2 antibodies. Recently, we have cloned the variable region genes of FU-MK-1 2) and compared them with those of MAbs GA733 and CO17-1A.…”

Normal tissue reactivity of four anti‐tumor monoclonal antibodies of clinical interest

“…This assay was described in detail by Mattes et al (1989 MOv19 reacted in the pancreas strongly with ducts, with weaker staining of acinar cells (Fig. 2); in the cervix and uterus with only the luminal edge and secretions of glandular cells; in the bronchus with glandular cells; in the lung with epithelial cells and/or secretions (Fig.…”