As a preeminent contract antibody development company, Creative Biolabs offers high-quality in vitro diagnostic (IVD) antibody development services targeting a wide range of biomarkers. Here, we focus on the complement C3f marker of osteoarthritis. We are committed to providing the highest quality of custom services and products at the most reasonable prices.

Complement C3f

C3f is a complement fragment released during the catabolic degradation of C3b by Factor H after C3 activation. Fragments or variants of C3f are modified, especially truncated, forms of C3f or forms in which one, two, three, four or more amino acids has been changed, deleted, added, substituted or otherwise modified. In particular fragments or variants include truncated fragments and variants in which 1, 2, 3, 4 or more amino acids have been removed from the C-terminal end of the peptide. Fragments and variants are preferably functional, that is to say, they have similar properties to the entire protein and are bound specifically by similar binding molecules such as antibodies.

Location of the C3F/S Polymorphism in Human Complement Component C3. Fig.1 Location of the C3F/S Polymorphism in Human
Complement Component C3. (Brown, KM. 2006

Complement C3f Marker of Osteoarthritis

An attractive method for osteoarthritis (OA) staging is the measurement of biochemical markers in biological fluids, which could reflect dynamic and quantitative changes in joint remodeling and therefore disease progression. Proteome analysis has been recognized as one of the most effective tools to explore biomarkers as it can furnish a wealth of information in both diagnosis and prognosis of diseases.

C3f peptide is a fragment released during the catabolic degradation of C3b by Factor H after C3 activation36. C3f is further degraded to form C3f-des-Arg (peptide mass of 1865 Da) and variants by carboxypeptidase N. Preliminary proteomics study on serum samples and synovial fluids of OA patients revealed the presence of C3f peptides in both fluids, but also in 3/7 paired RA serum/synovial fluid. However, as for V65 vitronectin fragment, C3f peptide was found to have some diagnostic values in OA, with a global sensitivity (all OA subsets) of 87% and a specificity of 92%. Furthermore, C3f peptide serum levels were significantly (and positively) correlated with V65 vitronectin serum levels in OA patients tested. Interestingly, vitronectin is also involved in the complement cascade, inhibiting the assembly of the membrane attack complex. Finally, C3f biomarker showed also significant negative correlations with serum levels of aggrecan and pyd.

IVD Antibody Development Services Targeting Complement C3f Marker

IVD antibodies have been commonly used in immunodiagnostic kits for disease diagnosis and prognosis. Creative Biolabs has built a versatile IVD platform to provide custom biomarker-specific IVD antibody development services to global clients. Along with over a decade of rich experience in providing excellent custom services for IVD antibody discovery, our services can totally meet your special requirements.

In addition, Creative Biolabs provides one-stop diagnostic immunoassay development services, including feasibility analysis, assay design, assay protocol establishment, validation, and production. If you are interested in our services, please do not hesitate to contact us for more details.


  1. Brown, KM. (2006). “Influence of donor C3 allotype on late renal-transplantation outcome.” N Engl J Med 354(19): 2014-2023.

Online Inquiry

*E-mail Address:
*Service & Products Interested:
Project Description:
*Verification Code:
Please input "biolabs"(case insensitive) as verification code.

Contact Us

45-1 Ramsey Road, Shirley, NY 11967, USA
Tel: 1-631-381-2994
Fax: 1-631-207-8356
Heidenkampsweg 58, 20097 Hamburg, Germany
Tel: 44-207-097-1828
Follow us on:
Copyright ©2011 - 2020 Creative Biolabs.