Complete and partial deficiencies of complement factor D in a Dutch family.
A young man suffering from recurrent Neisseria infections was shown to lack detectable serum complement factor D hemolytic activity. Addition to the patient's serum of purified factor D to a final concentration of 1 microgram/ml resulted in full restoration of the activity of the alternative pathway. Using an enzyme-linked immunosorbent assay, it was shown that the patient's serum did not contain measurable amounts of factor D antigen either. The sister, the father, as well as the parents of the mother had factor D levels within the normal range, and the factor D level of the mother was decreased. The capacity of the patient's serum, at concentrations up to 5%, to promote phagocytosis of Escherichia coli by normal human granulocytes was low when compared to normal serum. Substitution of the patient's serum with purified factor D resulted in a full restoration of opsonic activity. This study describes the first complete deficiency of factor D, and demonstrates its possible relation to recurrent Neisseria infections.
Hiemstra
P S
PS
Department of Nephrology, University Hospital Leiden, The Netherlands.
Langeler
E
E
Compier
B
B
Keepers
Y
Y
Leijh
P C
PC
van den Barselaar
M T
MT
Overbosch
D
D
Daha
M R
MR
D000328:Adult; D003166:Complement Activating Enzymes / Q000172:deficiency*; D011416:Complement Factor D / Q000172:deficiency* / Q000235:genetics / Q000627:therapeutic use; D015941:Complement Hemolytic Activity Assay; D003170:Complement Pathway, Alternative; D004926:Escherichia coli; D006069:Gonorrhea / Q000209:etiology*; D006801:Humans; D008297:Male; D008585:Meningitis, Meningococcal / Q000209:etiology*; D010375:Pedigree; D010587:Phagocytosis; D018805:Sepsis / Q000209:etiology
D003166:Complement Activating Enzymes; C493488:CFD protein, human; D011416:Complement Factor D