Chromium-release assay

Colsky AS, Peacock JS. 1990. Sodium pyruvate inhibits the spontaneous release of 51Cr from RBC in chromium release assays. J Immunol Methods 129 139-141. 

Nouri AME, Mansouri M, Hussain RF, et al. 1995. 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. J Immunol Methods 180 63-68. 

OVCAR is a human ovarian cell line that expresses STn on the cell surface. OVCAR was obtained from American Type Culture Collection (Bethesda, MD), grown and then placed in standard chromium release assay 17). Mononuclear cells from patients were incubated in the presence or absence of Interleukin 2 (IL2) (Genzyme, Cambridge, MA) at a concentration of 10 cells/ml with 100 units of IL2 for 48 hours -72 hours. Cells were washed and used as effector cells in a standard four hour killing assay as previously described (77). Fifty three... 

NK Cell Function Assays. The ICH S8 guidance specifically mentions the chromium-release assay as a means to assess NK cell function but suggests... 

Flow cytometry has been used successfully for analysis of apoptosis. Annexin V/Propidium iodide assay in this technique can differentiate between dead and live cells.This assay has been shown to provide a single-cell-based, rapid, quantitative, and sensitive assay to detect lymphocyte-mediated target cell killing in various animal models. Unlike conventional chromium release assays, the FC assay enables monitoring of cellular immune responses in real time and at the single-cell level using diverse fluorescence detection methods such as flow cytometry and fluorescence and CLSM [48]. 

A prerequisite for CTL-mediated immune response is the formation of the MHC-class I-peptide complex and subsequent recognition by the T-cell repertoire, which can be analyzed in cell lysis assays with MCr-loaded target cells. Chromium release is a measure for peptide-induced cell lysis by CTL, and indicates the potency of the peptide to serve as an allele-specific epitope. A synthetic epitope has been identified with the peptide library approach to elucidate the molecular basis for the observed cross-recognition of two ligands by a single receptor [53]. 

For cytotoxicity experiments, a number of methods have been published (1,2,25,28,29). The principle of the assay is identical to that of chromium release (Fig 6). There are three methods to label the cells Europium-DTPA into cells after dextran sulphate treatment, incorporation (1,2,25) by electroporation incorporation of europium chloride DTPA (28) or by use of a new membrane penetrating fluorescent ligand (29) (Figure 8). All methods give comparable results to the use of a chromium label,however there are a number of distinct advantages besides the obvious radioactivity issue. Europium labelled cells once labelled can be stored for up to 3 -4 months at -20 C (27). The labelling procedure takes approximately 10-20 minutes. The label does not bind to any cellular components therefore has a higher release rate, thus shorter (2 instead of 4 hours) incubation times can be considered. 

Suhrbier, A., A. Fernan, S.R. Burrows, A. Saul, and D.J. Moss. BLT Esterase Activity as an Alternative to Chromium Release in Cytotoxic T Cell Assays [published erratum appears in J Immunol Methods 1992 Apr 8 148(l-2) 265]. 145 ... 

The classical assay that has been used for years to monitor cytotoxicity is the Cr release assay. Briefly, the target cells in either ADCC or CDC assay are labeled with radioactive chromium. In an ADCC assay the target cells with... 

Wallace D, Hildesheim A, Pinto LA. Comparison of benchtop microplate beta counters with the traditional gamma counting method for measurement of chromium-51 release in C5dotoxic assays. Clin Diagn Lab Immunol 2004 11 255-260. 

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