Simplified cell labelling with indium–111 acetylacetone

Abstract

Isolated cells labelled by means of 111 In-oxine (8-hydroxyquinoline) have been found clinically acceptable for the diagnosis of abscesses (Thakur et al., 1977) and vascular thrombi (Goodwin et al., 1978), as well as useful in research on cell migration and survival in animals (Rannie et al., 1977) and man (Lavender et al., 1977). Attention has recently been drawn to the detrimental effect this method of labelling may have on cells (Segal et al., 1978; Danpure et al., 1979; Silvester 1979). In part, damage is attributable to the soft radiation (Auger electrons) emitted in the decay of intra-cellular 111In, but further damage may also be caused by a too-high oxine concentration, or by the presence of heavy-metal impurities. With care these problems may be overcome, but a further hazard remains: the 111In-oxine complex is prepared and dispensed in ethanol solution, which itself can be toxic when added to the washed-cell suspensions (Atkinson et al., and which it is inconvenient to store and handle.