C1q is useful for the detection of circulating immune complexes. The formation of immune complexes by the interaction of antibodies with antigens is a component of the normal immune response. However, immune complexes occasionally trigger a sequence of events that lead to disease. Circulating immune complexes appear in elevated levels in a variety of diseases (e.g. rheumatoid arthritis, systemic lupus erythematosus, glomerulonephritis, and schistosomiasis). (1-5)
The first component of the classical complement pathway is C1. C1 is a complex of three proteins, C1q, C1r, and C1s. The complete C1 complex is made up of one C1q, two C1r, and two C1s proteins.
The classical complement pathway is activated when C1q binds to the Fc regions of IgG or IgM bound to antigen. Although the binding of C1q to a single Fc region is weak, C1q can form tight bonds to a cluster of Fc regions. At this point C1 becomes proteolytically active. C1 can also activate spontaneously at 37?C. Spontaneous activation is inhibited by C1 inhibitor.
A glycoprotein, C1q is approximately 8% carbohydrate with the molecular weight of 460,000. (6) Recent developments in ELISA methodology have increased the sensitivity and therefore the diagnostician's ability to quantitate circulating immune complexes using C1q.
Source:Purified C1q from goat serum.
Storage and Stability:Aliquot to avoid repeated freezing and thawing and store at -70°C. Aliquots are stable for 6 months after receipt. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
仕様
Size：1mg
Source Antigen：Goat serum
Grade：Purified
Purity：C1q is dissociated from the C1 complex and purified by a combination of chromatographic and biochemical processes. This product precipitates heat aggregated human IgG in a double immunodiffusion assay.
Form：Supplied as a frozen liquid in 0.05M Tris, pH 7.2, 0.5M sodium chloride, 1mM EDTA.
