Semiquantitative in vitro binding assay of indium-111-labeled monoclonal antibodies to human cancer and normal tissues.

We have developed a simple in vitro method for the semiquantitative assessment of the radiolabeled antibody binding to cancer and normal tissues. Indium-111-labeled F(ab')2 fragments of 17-1A and 19-9 monoclonal antibodies with well-characterized specificity for gastrointestinal cancer demonstrated similar binding properties between cultured cancer cells and membrane fractions of homogenates prepared from tumor tissues. All of the 17 colon cancer specimens and seven (64%) of 11 gastric cancer specimens obtained by surgery showed positive binding with 17-1A. Specific binding of 19-9 was observed in 9 (53%) colon cancers and 4 (36%) gastric cancers. However, some normal colon tissues were also positive with 111In-labeled 17-1A. Relative levels of CA 19-9 antigen expression, determined by the binding with radiolabeled antibodies, correlated with percent positive cells determined by the immunohistochemical assays. Furthermore, membrane fractions could be cryopreserved without losing antibody-binding activity. These results indicate that this assay can be used for testing the immunoreactivity of radiolabeled anti-tumor antibodies and in vitro binding properties to cancer and normal tissues.

[1]  J. Douillard,et al.  Immunohistochemical antigenic expression and in vivo tumor uptake of monoclonal antibodies with specificity for tumors of the gastrointestinal tract. , 1986, Cancer research.

[2]  J. Douillard,et al.  Monoclonal antibodies specific immunotherapy of gastrointestinal tumors. , 1986, Hybridoma.

[3]  J. Johnson,et al.  Biochemical and epitope analysis of the 17-1A membrane antigen. , 1986, Hybridoma.

[4]  H. Sakahara,et al.  Effect of DTPA conjugation on the antigen binding activity and biodistribution of monoclonal antibodies against alpha-fetoprotein. , 1985, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[5]  R. Dillman,et al.  Radioimmunodetection of melanoma utilizing In-111 96.5 monoclonal antibody: a preliminary report. , 1985, Radiology.

[6]  P. Doherty,et al.  A simple in vitro method of screening panels of monoclonal antibodies for tumor binding. , 1985, Journal of immunological methods.

[7]  P. Bunn,et al.  Determination of the immunoreactive fraction of radiolabeled monoclonal antibodies by linear extrapolation to binding at infinite antigen excess. , 1984, Journal of immunological methods.

[8]  M. Herlyn,et al.  Tumor localization in patients by radiolabeled monoclonal antibodies against colon carcinoma. , 1983, Cancer research.

[9]  R. L. Childs,et al.  Radioactive labeling of antibody: a simple and efficient method. , 1983, Science.

[10]  M. Herlyn,et al.  Gastrointestinal cancer-associated antigen in immunoperoxidase assay. , 1982, Cancer research.

[11]  M. Herlyn,et al.  Colorectal carcinoma antigens detected by hybridoma antibodies , 1979, Somatic cell genetics.

[12]  M. Herlyn,et al.  Colorectal carcinoma-specific antigen: detection by means of monoclonal antibodies. , 1979, Proceedings of the National Academy of Sciences of the United States of America.

[13]  J. Brown,et al.  Quantitative analysis of melanoma-associated antigen p97 in normal and neoplastic tissues. , 1981, Proceedings of the National Academy of Sciences of the United States of America.