Inhibition of C1q functions by RHP, a protein elevated in sera from patients with rheumatoid arthritis.
We have previously shown that serum levels of C1q, unbound to C1r X C1s, are elevated in rheumatoid arthritis. We have also shown that RHP, a newly described serum protein which affects the C1q-anti C1q precipitin reaction, is also present at elevated levels in rheumatoid arthritis. We now show that RHP inhibits the hemolytic activity of C1q, disaggregates C1, and inhibits the ability of C1q bound to latex beads or to aggregated IgG to enhance the oxidative metabolism of neutrophils.
Rosano
C L
CL
Research Service, Veterans Administration Medical Center, Albany, NY.
Braun
C B
CB
Hechemy
K E
KE
Parhami
N
N
Satoh
P S
PS
Hurwitz
C
C
D000327:Adsorption; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000276:immunology; D001798:Blood Proteins / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D003166:Complement Activating Enzymes / Q000502:physiology*; D003172:Complement C1 / Q000378:metabolism / Q000502:physiology*; D003174:Complement C1 Inactivator Proteins; D015922:Complement C1q; D006461:Hemolysis; D006801:Humans; D007122:Immunoelectrophoresis; D007074:Immunoglobulin G / Q000378:metabolism; D008163:Luminescent Measurements; D008863:Microspheres; D009504:Neutrophils / Q000378:metabolism; D010100:Oxygen / Q000097:blood
D001798:Blood Proteins; D003172:Complement C1; D003174:Complement C1 Inactivator Proteins; D007074:Immunoglobulin G; C045510:RHP protein, human; D015922:Complement C1q; D003166:Complement Activating Enzymes; D010100:Oxygen; D002118:Calcium