C1q Antibody (Polyclonal)

The C1q molecule is a large protein with a molecular weight of 410 kD. This hexamer is composed of three unique protein subunits (A, B, and C) with molecular weights of 29, 26, and 22 kD respectively, and is present in normal human serum at an approximate concentration of 70 μg/mL. The assembled C1q molecule contains a central core or stalk, six collagen-like domains and six globular protein heads, resulting in a the appearance of a “bouquet of tulips.” The globular or terminal regions are responsible for binding the Fc portion of immunoglobulin (IgM, and IgG) . C1q is one of three subcomponents that together make the first component of the classical complement pathway, C1. C1q complexes with two C1s and two C1r components, and together, they form the C1 complex. Initiation of the classical complement pathway occurs when C1q binds with IgM or IgG containing antigen-antibody complexes.

The Anti-human C1q was tested against normal human plasma by double immunodiffusion, one-dimensional immunoelectrophoresis, two-dimensional immunoelectrophoresis, and quantitative rocket immunoelectrophoresis. The antiserum was determined to be monospecific for C1q at varying concentrations.