Technetium-labelled autologous lymphocytes: clinical protocol for radiolabelling using a high concentration and low volume of 99Tcm-exametazime.

ABSTRACT

Little clinical work has been performed using technetium-labelled lymphocytes due to the difficulty of effecting an imaging dose of technetium on the small number of lymphocytes available. We have successfully labelled lymphocytes using a high concentration and low volume of 99Tcm-exametazime. In eight readings from three patients and two volunteers, the labelling efficiency was 27% (4 S.D.). The radiolabel was stable in plasma in vitro up to 4 h. Viability of the lymphocytes as determined by trypan blue exclusion was greater than 95%.