THE USE OF RADIOACTIVE CHROMIUM 51 AS AN ERYTHROCYTE TAGGING AGENT FOR THE DETERMINATION OF RED CELL SURVIVAL IN VIVO 1.2
Journal/Book: Reprinted from THE JOURNAL OF CLINICAL INVESTIGATION Vol. XXXII No. 12 pp. 1260-1276 December 1953 Printed in U. S. A.. 1953;
Abstract: (From the Robert Dawson Evans Memorial Laborstory Massachusetts Memorial Hospitals and the Department of Medicine Boston University School of Medicine Boston Mass.) SUMMARY 1. Erythrocytes in ACD whole blood mixture combine rapidly and firmly with the radioactive chromate ion. After equilibration for three hours at 4 to 6° C. 60 per cent was bound to the red blood cells and 90 per cent was fixed after equilibration for one hour at 25 to 26° C. This is true of both freshly drawn blood and blood stored at 4° C. for as long as thirty-six days. The concentration of this chromate salt shows no marked effect on the rate of Cr51 uptake within the limits of 0.25 to 9.5 micrograms. The rate of erythrocyte Cr51 uptake increased inversely with the pH within the observed range of 6.0 to 7.2. 2.Post-transfusion survival as determined by the selective agglutination method of erythrocytes tagged with sodium chromate in concentrations of less than 10 micrograms per ml. of whole blood is 2 to 10 per cent shorter than the post-transfusion survival of nonchromated cells. This somewhat shorter survival of the chromated cells may or may not be within the range of the normal biological variations. 3. Na2Cr51O4 released from destroyed transfused erythrocytes is not re-utilized to tag the recipient's own red blood cells. 4. The concentration of Cr51 in the circulating donor erythrocytes decreases slowly at an exponential rate with a half-life 77 ± 12 days. This may be due to elution of Cr51 from the circulating donor cells. 5. The survival of stored blood can be measured accurately by the chromium tagging technique for a period of forty-eight hours after transfusion without correcting for the small amount of chromium leakage. If corrections for the amount of Cr51 elution can be made the method would allow measurement of post-transfused erythrocytes for periods of as long as three months. . . .