Studies on the oxygen transport in the clinical association between Hb-S and Hb-C.

The whole blood oxygen affinity of a Negro carrier of SC disease was found to be characterized by some right-shifted p50 and clearly increased Bohr effect, whereas the isolated and purified Hb-S and Hb-C exhibited slight deficiencies mainly of the Bohr effect. The right-shifted p50 from whole blood can be easily explained by the mild anemia with a parallel increase of 2,3-diphosphoglycerate (DPG), whereas the functional discrepancies between whole blood function and that of the purified Hb-S and C could be due, at least in part, to the presence in vivo of consistent amounts of hybrid Hb tetramers of the type alpha alpha beta S beta C. Unfortunately, the mechanism promoting the formation (or dissolution) of hybrids are fundamentally unknown; so, either their presence and functional properties are very difficult to be explored.