Anti-C5/C5a Antibody Picoband® Fluoro488 Conjugated

C5a is a protein fragment released from complement component C5. This gene is mapped to 9q33.2. The protein encoded by this gene is the fifth component of complement, which plays an important role in inflammatory and cell killing processes. This protein is comprised of alpha and beta polypeptide chains that are linked by a disulfide bridge. An activation peptide, C5a, which is an anaphylatoxin that possesses potent spasmogenic and chemotactic activity, is derived from the alpha polypeptide via cleavage with a convertase. The C5b macromolecular cleavage product can form a complex with the C6 complement component, and this complex is the basis for formation of the membrane attack complex, which includes additional complement components. Mutations in this gene cause complement component 5 deficiency, a disease where patients show a propensity for severe recurrent infections. Defects in this gene have also been linked to susceptibility to liver fibrosis and to rheumatoid arthritis.

Strongly expressed in placenta. Expressed at lower levels in heart, pancreas, kidney and brain. Expressed in endothelial cells. Isoform alpha was found to be the predominant isoform. Isoform beta was not found in pancreas and brain. .

Derived from proteolytic degradation of complement C5, C5 anaphylatoxin is a mediator of local inflammatory process. Binding to the receptor C5AR1 induces a variety of responses including intracellular calcium release, contraction of smooth muscle, increased vascular permeability, and histamine release from mast cells and basophilic leukocytes. C5a is also a potent chemokine which stimulates the locomotion of polymorphonuclear leukocytes and s their migration toward sites of inflammation. .

1. Delgado-Cervino, E., Fontan, G., Lopez-Trascara, M. C5 complement deficiency in a Spanish family: molecular characterization of the double mutation responsible for the defect. Molec. Immun. 42: 105-111, 2005. 2. Pfarr, N., Prawitt, D., Kirschfink, M., Schroff, C., Knuf, M., Habermehl, P., Mannhardt, W., Zepp, F., Fairbrother, W. G., Loos, M., Burge, C. B., Pohlenz, J. Linking C5 deficiency to an exonic splicer enhancer mutation. J. Immun. 174: 4172-4177, 2005. Note: Erratum: J. Immun. 182: 5152 only, 2009.