The Properdin System and Immunity. Iv. The Hemolysis of Erythrocytes From Patients With Paroxysmal Nocturnal Hemoglobinuria 1

Hereditary deficiency of the sixth component of complement in man. I. Immunochemical, biologic, and family studies.

“…In contrast, C2-deficient human serum, shown to have an intact alternate pathway function but to totally lack an operative classical pathway, did support lysis in acidified serum but not in the sugar water test (Table V). These data support the conclusion that the lysis of PNH RBC proceeds via the alternate pathway in the acidified serum test (49)(50)(51), and via the classical pathway in the sugar water test. On the other hand, Logue, Rosse, and Adams (51) observed significant but subnormal lysis of PNH RBC incubated at low ionic strength with hereditary angioedema serum which had been incubated at 370C immediately before testing in order to deplete residual C4.…”

Homozygous human C3 deficiency. The role of C3 in antibody production, C-1s-induced vasopermeability, and cobra venom-induced passive hemolysis.

“…Personal communication. (14) and that this lysis requires an intact alternative pathway (20)(21)(22)(23). The failure, therefore, of the patient's serum to produce lysis of PNH erythrocytes is no surprise.…”

Mechanisms of Immune Lysis of the Red Cells in Hereditary Erythroblastic Multinuclearity with a Positive Acidified Serum Test and Paroxysmal Nocturnal Hemoglobinuria

“…7). The fact that many molecules of C3 are bound to the membrane of red cells surviving lysis by antibody and complement (18,32) (3,4,36). Lysis occurred equally well using adsorbed serum, and C4 was not fixed to the membrane during lysis (Table VII and VIII). PNH red cells, like HEMPAS red cells, are lysed by small amounts of anti-I and complement, but the mechanism appears to be different.…”

“…The red cells of patients with paroxysmal nocturnal hemoglobinuria (PNH)1 have been extensively studied and have been shown to consist of at least two populations, one of which is markedly sensitive to the lytic action of complement (1,2). This sensitivity is apparent when complement is activated either by antibody or by the alternate (properdin) pathway (3)(4)(5)(6). The latter mechanism of activation is responsible for the lysis of PNH cells in acidified normal serum (3,4).…”

“…This sensitivity is apparent when complement is activated either by antibody or by the alternate (properdin) pathway (3)(4)(5)(6). The latter mechanism of activation is responsible for the lysis of PNH cells in acidified normal serum (3,4). Crookston et al reported that the red cells of patients with a form of congenital dyserythropoietic anemia characterized by multinucleated erythroblasts, are also lysed in acidified normal serum (7).…”