Activation of the alternative pathway of complement by monosodium urate monohydrate crystals and other inflammatory particles.
Activation of serum C3 by monosodium urate monohydrate (MSU) crystals and other particles was determined by immunofixation following electrophoretic separation of C3 and its activation products. Densitometry allowed quantitation of results. MSU, hydroxyapatite, brushite, and calcium pyrophosphate dihydrate crystals split C3 under conditions which demonstrate activation via the alternative pathway (AP). Quantitatively similar results were obtained in immunoglobulin deficient serum. Activation was crystal specific and was reduced by heating, grinding, sonication, and aging of crystals. Other inflammatory particles (e.g., blackthorn) activated C3 via the AP: noninflammatory particles (e.g., diamond) caused insignificant activation. It is suggested that particle-induced activation of the alternative pathway of complement may be important in the initiation of crystal-induced synovitis.
D000361:Agammaglobulinemia / Q000276:immunology; D002130:Calcium Phosphates / Q000494:pharmacology; D003167:Complement Activation / Q000187:drug effects*; D003176:Complement C3 / Q000276:immunology*; D003170:Complement Pathway, Alternative / Q000187:drug effects*; D003460:Crystallization; D004492:Edetic Acid / Q000494:pharmacology; D004533:Egtazic Acid / Q000494:pharmacology; D006801:Humans; D007249:Inflammation / Q000276:immunology*; D008274:Magnesium / Q000494:pharmacology; D014527:Uric Acid / Q000494:pharmacology*; D015054:Zymosan / Q000494:pharmacology
D002130:Calcium Phosphates; D003176:Complement C3; D014527:Uric Acid; D004533:Egtazic Acid; D015054:Zymosan; D004492:Edetic Acid; D008274:Magnesium