The Life-span of Complement-sensitive and -insensitive Red Cells in Paroxysmal Nocturnal Hemoglobinuria

The survival of the complement-sensitive and complement-insensitive red cells in four patients with paroxysmal nocturnal hemoglobinuria (PNH) have been determined using either a cohort or a random label. The complement-sensitive cells have a very short survival (T ½) of less than 6 days by either technique). The complement-insensitive cells have a longer survival, with a large component of random destruction. The complement-sensitive cells are not changed into complement-insensitive cells. The proportion of complement-sensitive cells produced per day is very much greater than the proportion of these cells in the circulating blood.