IN-111-LABELED LEUKOCYTES FOR LOCALIZATION OF ABSCESSES - PREPARATION, ANALYSIS, TISSUE DISTRIBUTION, AND COMPARISON WITH GA-67 CITRATE IN DOGS

Abstract

Leukocytes were labeled with In-111-8-hydroxyquinoline complex. Of the initial activity 75-85% was obtained in the complex form of which 75-95% is incorporated with the leukocytes. The polymorphonuclear leukocytes are predominantly labeled, and the label was stable for at least 27 h after in vivo administration. The radioactivity clears from the circulating blood with a half time of 8-9 h and accumulates in normal liver and spleen and in experimentally induced abscesses. The cells which were labeled and damaged by heat concentrate mainly in the lungs. The in vivo distribution of the In-111 labeled cells was compared with the Ga-67 administered as citrate. The abscess to blood ratios of the In-111 activity varied between 35-117, compared to 1.2-8 of the Ga-67. The abscess to liver, spleen and kidney ratios are several fold higher with In-111 leukocytes than with Ga-67 citrate. These results plus the suitable physical characteristics of In-111 make the labeled leukocytes a better agent for the localization of abscesses.