Complement C4 Protein (Active)

Catalog# BNP1007

Lot # Check on the product label

Size 1 mg

Description

Purified human Complement C4 protein.

Synonyms Complement C4-A, Acidic complement C4, C3 and PZP-like alpha-2-macroglobulin domain-containing protein 2, C4A, CO4, CPAMD2

Source Human plasma

Purity >90% by SDS-PAGE

Formulation Liquid

Application

ELISA

Other applications have not been tested.

The optimal dilutions should be determined by end user.

Storage buffer

Each vial contains 10mM PBS (pH7.4).

Storage & Expiration

Ship at 4℃. Upon receipt, aliquot and store at -20℃ or -80℃ for long term.

Avoid repeated freeze and thaw cycles.

Background

Complement C4 encodes the basic form of complement factor 4, part of the classical activation pathway. The protein is expressed as a single chain precursor which is proteolytically cleaved into a trimer of alpha, beta, and gamma chains prior to secretion. The trimer provides a surface for interaction between the antigen-antibody complex and other complement components. The alpha chain may be cleaved to release C4 anaphylatoxin, a mediator of local inflammation. Deficiency of this protein is associated with systemic lupus erythematosus. This gene localizes to the major histocompatibility complex (MHC) class III region on chromosome 6. Varying haplotypes of this gene cluster exist, such that individuals may have 1, 2, or 3 copies of this gene. In addition, this gene exists as a long form and a short form due to the presence or absence of a 6.4 kb endogenous HERV-K retrovirus in intron 9. 

Reference

1. Rosenfeld, S. I., Ruddy, S., Austen, K. F. Structural polymorphism of the fourth component of human complement. J. Clin. Invest. 48: 2283-2292, 1969.

2. Roos, M. H., Mollenhauer, E., Demant, P., Rittner, C. A molecular basis for the two locus model of human complement component C4. Nature 298: 854-856, 1982.

3. Schneider, P. M., Witzel-Schlomp, K., Rittner, C., Zhang, L. The endogenous retroviral insertion in the human complement C4 gene modulates the expression of homologous genes by antisense inhibition. Immunogenetics 53: 1-9, 2001.