Complement sensitivity of erythrocytes in a patient with inherited complete deficiency of CD59 or with the Inab phenotype.
We investigated the complement sensitivity of erythrocytes from three patients, one with inherited complete deficiency of CD59, one with the Inab phenotype, and one with paroxysmal nocturnal haemoglobinuria (PNH). The complement lysis sensitivity units on the erythrocytes were 11.7, 4.6, and 47.6 for inherited CD59 deficiency, Inab phenotype, and PNH, respectively. Two-colour flow cytometric analysis showed that the erythrocytes from the three patients consisted of a single population negative for CD59, negative for decay accelerating factor (DAF), and negative for both proteins, respectively. In addition, only the Inab phenotype patient had no haemolysis in vivo. These facts suggest that CD59 deficiency plays a more important role than DAF deficiency in complement-mediated haemolysis in vitro and in vivo, and that deficiency of both proteins, but not CD59 or DAF alone, causes complement sensitivity corresponding to that of PNH III erythrocytes in vitro.
Shichishima
T
T
First Department of Internal Medicine, Fukushima Medical University, Fukushima, Japan.
Saitoh
Y
Y
Terasawa
T
T
Noji
H
H
Kai
T
T
Maruyama
Y
Y
D000328:Adult; D001789:Blood Group Antigens / Q000276:immunology; D018958:CD55 Antigens / Q000276:immunology; D003165:Complement System Proteins / Q000276:immunology*; D004912:Erythrocytes / Q000276:immunology*; D006457:Hemoglobinuria, Paroxysmal / Q000276:immunology*; D006461:Hemolysis / Q000276:immunology; D006801:Humans; D008297:Male; D010641:Phenotype; D017463:Receptors, Complement 3b / Q000172:deficiency* / Q000276:immunology
D001789:Blood Group Antigens; D018958:CD55 Antigens; D017463:Receptors, Complement 3b; D003165:Complement System Proteins