The Labelling of Human Platelets With Radiochromate

Abstract

SUMMARY.A technique for the labelling of human blood platelets with radioactive sodium chromate is described, and is compared with those previously in use. The uptake of radiochroinate by platelets is greatest when the platelet suspension is of small volume, plasma protein is absent, and the sodium chromate concentration is 0-2 to 3-0 ng. per lO'" platelets. The rate of the reaction is not a£fccted by its duration up to 40 minutes, but is enhanced by an increase in temperature. About one-third of platelets in suspensions labelled as described are viable, and survive in the circulation for 8-10 days.

Effect of injected heparin on platelet levels in man

“…PLATELET LABELLING WITH RADIOCHROMATE Platelets from each subject were isolated, labelled with radio-55 chromate as previously described (Davey and Lander, 1963), and reinfused into their donors for determination of their survival in vivo. The present studies were undertaken in each subject during a period between three and 36 hours after infusion, when blood and platelet radioactivity are sufficiently stable to serve as indicators of circulating platelet levels (Davey andLander, 1964a, 1964b).…”

“…The present studies were undertaken in each subject during a period between three and 36 hours after infusion, when blood and platelet radioactivity are sufficiently stable to serve as indicators of circulating platelet levels (Davey andLander, 1964a, 1964b).…”

“…RADIOACTIVITY DETERMINATIONS were performed on aliquots of whole blood and of isolated platelets, as described previously (Davey and Lander, 1963). Clotting times (Lee White) were determined in untreated glass tubes at 37°C.…”

Reduced Platelet Survival in Patients with Starr-Edwards Prostheses

“…In all subjects infusion of the labelled platelets was followed by the normal phenomenon of transient " segregation " and subsequent re-entry into circulation of a proportion of the labelled platelets (Davey and Lander, 1964). However, as found by Aster and Jandl (1964), the degree of segregation is less when A.C.D. "…”

“…Details relating to each subject are included in the Table. Platelets from each subject were labelled with 70-100 microcuries of radiochromate in vitro and reinfused into the donor, in whom their behaviour, survival, and distribution in the body were studied. Details of the procedure employed have been described previously (Davey and Lander, 1963), except that the blood from which the platelets were separated was collected in the more acid solution of acid-citrate-dextrose (A.C.D. " S ") suggested by Aster and Jandl (1964), instead of in a solution of ethylenediaminetetra-acetic acid (E.D.T.A.…”