title: Cytotoxicity assays using cryopreserved target cells pre-labeled with the fluorescent marker europium.
abstract: We describe a method for standardizing cytotoxicity assays by the use of cryopreserved, fluorescently labeled target cells. The cells are labeled in batches with the fluorogenic element europium (Eu) and frozen in multiple aliquots. Replicate aliquots can be thawed on different days and used for cytotoxicity assays. Thawed pre-labeled cells from the same batch are killed reproducibly, allowing cytotoxicity assays to be standardized. The target cells need only be thawed, washed, counted for viability and used. The availability of pre-labeled, cryopreserved targets facilitates the assessment of cytotoxic activity of individual donors at different times. The method also simplifies the use of large panels of target cell types. By using this procedure it is not necessary to maintain active cultures of target cells, nor is it necessary to use and dispose of radioisotopes. These pre-labeled target cells can be used in various assays where the result is a destroyed target cell such as cell-mediated cytotoxicity, complement mediated cytotoxicity, or antibody-dependent cellular cytotoxicity.
authors.affiliation: Medical Products Department, E.I. DuPont de Nemours, Inc., Glenolden, PA 19036.
authors.forename: D T
authors.initials: DT
authors.lastname: Maley
authors.forename: P
authors.initials: P
authors.lastname: Simon
mesh_terms: D002470:Cell Survival; D015938:Complement Membrane Attack Complex / Q000276:immunology; D015925:Cryopreservation; D003601:Cytotoxicity Tests, Immunologic / Q000379:methods*; D005063:Europium; D005456:Fluorescent Dyes; D006801:Humans; D015979:Killer Cells, Lymphokine-Activated / Q000276:immunology; D015203:Reproducibility of Results; D014407:Tumor Cells, Cultured / Q000276:immunology
chemical_list: D015938:Complement Membrane Attack Complex; D005456:Fluorescent Dyes; D005063:Europium