Cell damage resulting from the labeling of rat lymphocytes and HeLa S3 cells with In-111 oxine.

Rat thoracic-duct lymphocytes and HeLa S3 cells were labeled in vitro with different amounts of indium-111 oxine. The labeled rat lymphocytes were tested for their ability to recirculate normally in syngeneic rats; the labeled HeLa S3 cells for their ability to divide to form colonies in tissue culture. Both cell types behaved normally by these criteria when labeled with small amounts of indium-111 oxine but at higher doses were obviously damaged. Evidence was obtained for the HeLa S3 cells that this damage was primarily radiation-induced. These findings may impose limitations on the use of In-111 oxine as a cell label for clinical purposes.