Transport of C-14-deferiprone in normal, thalassaemic and sickle red bloodcells

The transport of deferiprone (L1) in normal (N), sickle (S) and thalassaemi c (T) red blood cells (RBC) was determined by incubation with C-14-L1 at 37 degrees C. Following incubation with 0.5 mM C-14-L1 for 4 h, the intracell ular concentration of L1 in T RBC was 3 times higher than was found extrace llularly, In contrast, no concentration gradient across N and S RBC membran es was detected. Efflux studies showed that T RBC released only 17 +/- 2% o f C-14-L1 into the extracellular space. We hypothesize that L1 accumulation in T RBC results from their high content of chelatable iron and formation of large. hydrophilic L1-Fe(III) complexes trapped within the cytosol.