Improved ELISA proliferation assay (EPA) for the detection of in vitro cell proliferation by a new Ki-67-antigen directed monoclonal antibody (Ki-S3)

• Published in: Journal of immunological methods 1998-02, Vol.211 (1), p.43-50
• Main Authors: Frahm, S.O., Zott, B., Dworeck, C., Steinmann, J., Neppert, J., Parwaresch, R.
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Monoclonal - immunology; Biological and medical sciences; Cell cycle, cell proliferation; Cell Division; Cell physiology; Cell proliferation; Cells, Cultured; ELISA; Enzyme-Linked Immunosorbent Assay - methods; Evaluation Studies as Topic; Female; Fundamental and applied biological sciences. Psychology; Humans; Isotope Labeling; Ki-67; Ki-67 Antigen - immunology; Ki-S3; Leukocytes, Mononuclear - drug effects; Leukocytes, Mononuclear - immunology; Male; Mice; Mitogens - pharmacology; Molecular and cellular biology; Phytohemagglutinins - pharmacology; Sensitivity and Specificity; Staining and Labeling - methods; Thymidine - metabolism; Tritium
• ISSN: 0022-1759; 1872-7905
• DOI: 10.1016/S0022-1759(97)00175-0

We describe a simplified and improved proliferation assay based on a conventional ELISA system for the in vitro measurement of cellular proliferation (ELISA proliferation assay=EPA). The assay is based on a new monoclonal antibody (Ki-S3) to the proliferation-specific Ki-67-antigen and is carried out in 96-well microtiter plates using conventional immunoenzymatic methods. Ki-S3 is an immunoprecipitating monoclonal mouse IgG1 antibody, which recognizes a formalin-resistant epitope of the Ki-67 antigen. It can be used to measure proliferating cells in the cell cycle phases G1, S, G2 and M. In phytohemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMC) the absorbance values obtained with the EPA show a statistically significant correlation to the number of Ki-S3 positive cells in simultaneously immunostained cytospin slides ( r=0.88). A direct comparison with [ 3 H ]thymidine labeling reveals the test to be an equally sensitive method for monitoring cellular proliferation ( r=0.91). This assay is an improved ELISA proliferation assay, which is easy to perform, does not require time-consuming pretreatments and avoids the hazards of radioactive isotopes.