Red cell plasma membrane

Historical results obtained with Hb solutions were also confounded by the fact that many of these preparations were impure. One common impurity was fragments of the red cell plasma membrane, denoted as stroma. This stromal detritus was subsequently shown to be responsible, at least in part, for the kidney toxicity frequently observed after Hb infusion. For this reason, stroma must be rigorously excluded from Hb preparations. In addition to removing a source of... 

The average human red cell plasma membrane is lipid-rich with 240 million PL molecules, 190 million cholesterol molecules, 12 million glyco-lipid molecules and only 4 million protein molecules (Lux and Glader, 1981). The PLs of the red cell plasma membrane are asymmetrically distributed in the bilayer. The choline-containing PLs, PC and sphingomyelin represent 40% and 15%, respectively, of the total PL, and are enriched in the outer leaflet. In contrast, the amino PLs, PE and phospha-tidylserine (PS) are exclusively confined to the inner leaflet and constitute 35% and 15%, respectively, of total PLs. 

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