C4 polyclonal, anti-human

Quantity: 200 µl

Background:
The reactivity of the antiserum is restricted to C4. In immunoelectrophoresis and radial immunodiffusion (Ouchterlony), using various antiserum concentrations against fresh normal human plasma a single precipitin line is obtained which shows a reaction of identity with the precipitin line obtained with purified C4 protein. Activated C4b may also react with the antiserum. No reaction is obtained with any other plasma protein component or serum. In precipitating techniques as immunoelectrophoresis and single and double radial immunodiffusion (Mancini, Ouchterlony) to identify the presence of C4 binding protein or to determine its concentration. The presence of non-precipitating antibodies has not been assayed. This does not exclude the use of the antiserum in non-precipitating antibody-binding techniques if proper controls are included.

Isotype: Rabbit Polyclonal

Source: C4 and C2 represent substrates for activated C1. Both components are present in serum in an inert form. C4 is composed of 3 polypeptide chains of three different types, , , . One of the chains is cleaved by the action of activated C1, resulting in activation of C4 exposing an binding site for the next component in the sequence, C2. C4 has a molecular weight of 205.000 and is present in plasma in an average concentration of 600 ?g/ml. The activation of C4 yields two peptide fragments: C4a (MW 8,000) and C4b (MW 198,000). This process shows a considerable degree of similarity to the activation of the components C3 and C5. The C4 is isolated as a homogenous protein for use in antiserum production. Freund's complete adjuvant is used in the first step of the immunization procedure.

Form: Delipidated, heat inactivated, in PBS and 0.1% sodium azide.

Reactivity: human

Cross Reactivity:
Inter-species cross-reactivity is a normal feature of antibodies to Serum proteins, since homologous proteins of different species frequently share antigenic determinants. The degree of cross-reactivity is also dependent on the concentRations of the reactants and the sensitivity of the assay arrangement. This antiserum has been tested for cross-reactivity in double radial immunodiffusion with Bovine Serum and found negative.

Applications: Immunoprecipitation

Storage: Store at 4C, or in small aliquots at -20C.