title: Super-sensitive epithelial cell line and colorimetric assay to replace the conventional K562 target and chromium release assay for assessment of non-MHC-restricted cytotoxicity.
abstract: Using colorimetric MTT assay the susceptibility of a newly established bladder epithelial cell line, Fen cells was compared with conventional target cells, i.e., K562 and Daudi and other epithelial lines for investigation of non-specific killing activity (NK/LAK) of effector cells previously activated with interleukin-2 (IL-2). The results showed that Fen cell line was more sensitive than K562 and Daudi targets and this was seen whether the effector cells were IL-2-activated or not. The percent killing of effector cells from nine normal donors against Fen, K562 and Daudi targets at effector/target (E/T) ratio of 10/1 after IL-2 activation were 63.4 +/- 7.3, 42.6 +/- 4.3 (p = 0.0001) and 38.6 +/- 5.1 (p = 0.0001) respectively. The corresponding values for inactivated effector cells at 50/1, E/T ratio were 44.8 +/- 9.0, 25.1 +/- 8.3 (p = 0.0001) and 24.4 +/- 9.4 (p = 0.0001) indicating exquisite sensitivity of Fen cells to NK/LAK killing. The susceptibility of Fen cells was found to increase by pre-treatment of target cells with interferons (IFN). Thus the percent killing of untreated, IFN-alpha (1000 U/ml), beta (2000 U/ml) and gamma (100 U/ml) treated cells were 52%, 64% (p = 0.005), 70% (p = 0.001) and 67% (p = 0.001) respectively. These results indicated that Fen cells were more susceptible to NK/LAK killing than the conventional K562 and Daudi target cells. These results and the epithelial origin of Fen cells indicate that this cell line might prove to be a more realistic system to replace the conventional approach for assessment of NK/LAK activity in patients with cancer of epithelial origin.
authors.affiliation: Department of Medical Oncology, Royal London Hospital, UK.
authors.forename: A M
authors.initials: AM
authors.lastname: Nouri
authors.forename: M
authors.initials: M
authors.lastname: Mansouri
authors.forename: R F
authors.initials: RF
authors.lastname: Hussain
authors.forename: A V
authors.initials: AV
authors.lastname: Dos Santos
authors.forename: R T
authors.initials: RT
authors.lastname: Oliver
mesh_terms: D016923:Cell Death; D003124:Colorimetry / Q000379:methods*; D003601:Cytotoxicity Tests, Immunologic / Q000379:methods*; D003602:Cytotoxicity, Immunologic / Q000187:drug effects / Q000276:immunology*; D004848:Epithelium / Q000276:immunology / Q000473:pathology; D005260:Female; D006801:Humans; D007372:Interferons / Q000494:pharmacology; D007376:Interleukin-2 / Q000494:pharmacology; D015979:Killer Cells, Lymphokine-Activated / Q000276:immunology*; D007694:Killer Cells, Natural / Q000276:immunology*; D008297:Male; D012680:Sensitivity and Specificity; D013778:Tetrazolium Salts; D013844:Thiazoles; D014407:Tumor Cells, Cultured; D001749:Urinary Bladder Neoplasms / Q000276:immunology* / Q000473:pathology
chemical_list: D007376:Interleukin-2; D013778:Tetrazolium Salts; D013844:Thiazoles; D007372:Interferons; C022616:thiazolyl blue