Anti-Citrulline Monoclonal Antibody (Clone 1D9)

Citrulline is a noncoding amino acid that is produced by deimination of arginine through the post-translational modification citrullination.¹ Citrullination is catalyzed by protein arginine deiminases (PADs) that convert positively charged arginine to electrically neutral citrulline, decreasing the isoelectric point of the protein, altering the native protein structure, and influencing protein ionic interactions.² Protein citrullination has roles in many physiological and pathological processes, including autoimmunity, cancer, and neurodegenerative disorders.³ Citrullination of arginine 26 on histone H3 by PAD2 (Item No. 10785) displaces histone H3 from chromatin, resulting in chromatin decondensation and estrogen receptor α (ERα) transcriptional activation in a reporter assay.⁴ Citrullinated histones are also a component of neutrophil extracellular traps (NETs), a network of decondensed DNA and intracellular proteins secreted by neutrophils as a pathogen defense mechanism that is also a source of citrullinated autoantigens.⁵ Increased levels of antibodies to citrullinated protein antigens (ACPAs) are associated with increased disease severity in patients with rheumatoid arthritis.^6,7 Plasma levels of citrullinated histone H3 are increased in patients with advanced cancer, and citrullinated glial fibrillary acidic protein (citGFAP; Item No. 28622) has been found in postmortem hippocampus from patients with Alzheimer's disease.^8,9 Cayman's Anti-Citrulline Monoclonal Antibody (Clone 1D9) can be used for ELISA, immunofluorescence (IF), immunohistochemistry (IHC), immunoprecipitation (IP), and Western blot (WB) applications.

WARNING This product is not for human or veterinary use.

1. Yuzhalin, A.E. Citrullination in cancer. Cancer Res. 79(7), 1274-1284 (2019).

2. György, B., Tóth, E., Falus, A., et al. Citrullination: A posttranslational modification in health and disease. Int. J. Biochem. Cell Biol. 38(10), 1662-1677 (2006).

3. Lee, C.-Y., Wang, D., Wilhelm, M., et al. Mining the human tissue proteome for protein citrullination. Mol. Cell Proteomics 17(7), 1378-1391 (2018).

4. Zhang, X., Bolt, M., Guertin, M.J., et al. Peptidylarginine deiminase 2-catalyzed histone H3 arginine 26 citrullination facilitates estrogen receptor α target gene activation. Proc. Natl. Acad. Sci. USA 109(33), 13331-13336 (2012).

5. Gregori-Puigjané, E., Setola, V., Hert, J., et al. Identifying mechanism-of-action targets for drugs and probes. Proc. Natl. Acad. Sci. USA 109(28), 11178-11183 (2012).

6. Demoruelle, M.K., and Deane, K. Antibodies to citrullinated protein antigens (ACPAs): Clinical and pathophysiologic significance. Curr. Rheumatol. Rep. 13(5), 421-430 (2011).

7. Brewer, R.C., Lanz, T.V., Hale, C.R., et al. Oral mucosal breaks trigger anti-citrullinated bacterial and human protein antibody responses in rheumatoid arthritis. Sci. Transl. Med. 15(684), eabq8476 (2023).

8. Thålin, C., Lundström, S., Seignez, C., et al. Citrullinated histone H3 as a novel prognostic blood marker in patients with advanced cancer. PLoS One 13(1), e0191231 (2018).

9. Ishigami, A., Masutomi, H., Handa, S., et al. Mass spectrometric identification of citrullination sites and immunohistochemical detection of citrullinated glial fibrillary acidic protein in Alzheimer’s disease brains. J. Neurosci. Res. 93(11), 1664-1674 (2015).

Pasquero, S., Gugliesi, F., Biolatti, M., et al. Citrullination profile analysis reveals peptidylarginine deaminase 3 as an HSV-1 target to dampen the activity of candidate antiviral restriction factors. PLoS Pathog. 19(12), e1011849 (2023).