Measurements of cell-mediated cytotoxicity on target cells labelled with the indium-111-oxine complex.

The preparation is given of an 111indium-oxine complex that is non toxic and can label reproductively various types of cells. They retain the label for long periods (24 hours and more). This method gives parallel results for cell-mediated cytotoxicity measurements to Chromium-51 labelling and is found to have wider uses. It can label cells that release 51Cr too fast, makes possible long term measurements of cytotoxicity and accurate counts on small numbers of target cells.