title: A non-radioisotopic human natural killer cell assay using rhodamine-123 fluorescent dye as labelling probe.
abstract: A non-radioisotopic method for assessment of human natural killer (NK) cell activity in peripheral blood mononuclear cells (PBMC) was established by labelling K562 erythroleukemia target cells with a fluorescent dye, rhodamine-123 (Rh-123). The labelling and assay conditions were determined for minimizing spontaneous release (SR). In order to investigate whether NK activity assessed by measuring Rh-123 release agrees with the activity determined by a 51Cr release assay, the NK activity of PBMC was measured simultaneously by both assay methods. Statistical analysis demonstrates that NK activities determined by Rh-123 release correlate well with those measured by 51Cr release. The Rh-123 release assay under the conditions determined was found to be applicable to measurement of the enhanced NK activity resulting from pretreatment of effector leukocytes with interferon-alpha. It is concluded that the Rh-123 release assay with use of K-562 labelled target cells is practical for the assessment of human NK activity in laboratories where use of radioisotopes is not permitted or undesirable.
authors.affiliation: Fujimoto Pharmaceutical Corporation, Osaka, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Iwao
authors.forename: C
authors.initials: C
authors.lastname: Ochi
authors.forename: I
authors.initials: I
authors.lastname: Kurane
authors.forename: S
authors.initials: S
authors.lastname: Muraoka
mesh_terms: D002857:Chromium; D003601:Cytotoxicity Tests, Immunologic; D005456:Fluorescent Dyes; D006801:Humans; D016898:Interferon-alpha / Q000494:pharmacology; D007553:Isotope Labeling; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology*; D020112:Rhodamine 123; D012235:Rhodamines; D013997:Time Factors; D014407:Tumor Cells, Cultured
chemical_list: D005456:Fluorescent Dyes; D016898:Interferon-alpha; D012235:Rhodamines; D002857:Chromium; D020112:Rhodamine 123