Abcam, ab222866, Human Complement C4-Binding Protein ELISA Kit

Size: 1 x 96Tests
Human Complement C4-Binding Protein ELISA Kit is a Sandwich (quantitative) ELISA for the measurement of Human Complement C4-Binding Protein in Human in Biofluids samples.
Key facts
Detection method:Colorimetric,
Sample types:Cerebral Spinal Fluid, Saliva, Urine, Plasma, Milk, Serum,
Reacts with:Human,
Assay type:Sandwich (quantitative),
Sensitivity:= 0.14 ng/mL,
Range:0.938 - 60 ng/mL,
Assay time:4h,
Assay Platform:Pre-coated microplate (12 x 8 well strips)

Product details:
ab222866 Human Complement C4-Binding Protein ELISA Kit is designed for the quantitative measurement of Complement C4-Binding Protein in plasma, serum, urine, milk, saliva, cerebrospinal fluid (CSF), and cell culture samples.
The kit employs a quantitative sandwich enzyme immunoassay technique that measures human Complement C4-Binding Protein (C4BP) in less than 4 hours. A polyclonal antibody specific for human complement C4BP has been pre-coated onto a 96-well microplate with removable strips. Complement C4BP in standards and samples is sandwiched by the immobilized antibody and biotinylated polyclonal antibody specific for complement C4BP, which is recognized by a streptavidin-peroxidase conjugate. All unbound material is washed away and a peroxidase enzyme substrate is added. The color development is stopped and the intensity of the color is measured.
The entire kit may be stored at -20°C for long term storage before reconstitution - Avoid repeated freeze-thaw cycles.
Complement component C4-binding protein (C4BP) regulates the complement system by accelerating the decay of the complement component C3 convertase and by acting as a cofactor to the serine protease factor I in the degradation of C4b. C4BP is a high molecular mass (570 kDa) glycoprotein and is present in plasma in various isoforms with different alpha beta composition. The major form of C4BP is composed of seven identical 70-kDa alpha chains, each containing a binding site for the complement protein C4b, and a unique 45 kDa beta chain which contains a binding site for the vitamin K-dependent protein S. C4BP was overexpressed in the synovial membranes of patients with rheumatoid arthritis. It was detected in amyloid-beta plaques and on apoptotic cells.

Properties and Storage Information:
Shipped at conditions-Blue Ice, Appropriate short-term storage conditions--20°C, Appropriate long-term storage conditions-Multi, Storage information-Please refer to protocols

Supplementary Information:
This supplementary information is collated from multiple sources and compiled automatically.
C4 binding protein also known as C4BPB is a vital component of the complement system responsible for immune function. It has a molecular mass of approximately 570 kDa and is expressed mainly in liver tissues. C4BPB is a multi-chain protein complex consisting of several alpha and beta chains. This structure allows it to perform important roles in the regulation of immune responses. The presence of C4BPB can be detected in the serum where it acts to modulate the activity of complement C4 protein.
Biological function summary
C4 binding protein plays a defensive role in the immune system by regulating complement activation. It is part of a larger complex that controls the complement pathway which is integral to immune surveillance and removing pathogens. C4BPB functions primarily by binding to complement C4 preventing the formation of the C3 convertase which is an enzyme that amplifies the complement response. This binding action helps in stabilizing the protein C4 and complement C4 serum to avoid unnecessary immune reactions.
Pathways
The complement system pathway prominently features C4 binding protein. In the classical complement activation pathway C4BPB works closely with other proteins such as C3 and C4 to ensure regulatory balance. Its inhibitory action on the complement C4 pathway provides a safeguard against damage to host tissues during immune responses. The interplay between C4BPB and protein C4 offers a protective mechanism reducing excessive inflammation which can lead to tissue injury.
C4 binding protein holds relevance in conditions like rheumatoid arthritis and systemic lupus erythematosus (SLE). Both diseases involve dysregulation of the immune system where inappropriate complement activation occurs. C4BPB's ability to inhibit complement C4 activation suggests that disruptions in its function may contribute to the pathophysiology of these autoimmune disorders. Additionally the relationship between C4BPB and other complement proteins like C3 and C4 is critical in understanding the underlying mechanisms driving these diseases.