LL-37 Polyclonal Antibody

LL-37 is a cationic α-helical peptide expressed in human bone marrow, testis, granulocytes, gingival epithelium, and a variety of immune cells.¹ It is produced by proteolytic cleavage of the cathelicidin human cationic antimicrobial protein of 18 kDa (hCAP18).² LL-37 has antimicrobial and antiviral activity, and protein levels of LL-37 are increased in epithelial cells, macrophages, and neutrophils following bacterial infection in vitro.^1,3,4,5 It functions as a chemoattractant for human monocytes, neutrophils, and T cells, and induces chemokine secretion from epithelial cells in infected tissues.^6,2 LL-37 is a component of LPS-induced NETs produced from human neutrophils isolated from patients with systemic lupus erythrematosus (SLE) or individuals without SLE.⁷ It also enhances PMA- or S. aureus-induced formation of NETs.⁸ LL-37 can be citrullinated by protein arginine deiminase 2 (PAD2) and PAD4, a modification that reduces its antibacterial and antiviral activities.^9,5 Native, but not citrullinated, LL-37 prevents mortality in a mouse model of D-galactosamine-sensitized endotoxic shock.⁹ Cayman's LL-37 Polyclonal Antibody can be used for Western blot.

WARNING This product is not for human or veterinary use.

1. Weinberg, A., Krisanaprakornkit, S., and Dale, B.A. Epithelial antimicrobial peptides: Review and significance for oral applications. Crit. Rev. Oral Biol. Med. 9(4), 399-414 (1998).

2. Méndez-Samperio, P. The human cathelicidin hCAP18/LL-37: A multifunctional peptide involved in mycobacterial infections. Peptides 31(9), 1791-1798 (2010).

3. Rivas-Santiago, B., Hernandez-Pando, R., Carranza, C., et al. Expression of cathelicidin LL-37 during Mycobacterium tuberculosis infection in human alveolar macrophages, monocytes, neutrophils, and epithelial cells. Infect. Immun. 76(3), 935-941 (2008).

4. Gudmundsson, G.H., Agerberth, B., Odeberg, J., et al. The human gene FALL39 and processing of the cathelin precursor to the antibacterial peptide LL-37 in granulocytes. Eur. J. Biochem. 238(2), 325-332 (1996).

5. Casanova, V., Sousa, F.H., Shakamuri, P., et al. Citrullination alters the antiviral and immunomodulatory activities of the human cathelicidin LL-37 during rhinovirus infection. Front. Immunol. 11, 85 (2020).

6. Yang, B.D., Chen, Q., Schmidt, A.P., et al. LL-37, the neutrophil granule- and epithelial cell-derived cathelicidin, utilizes formyl peptide receptor-like 1 (FPRL1) as a receptor to chemoattract human peripheral blood neutrophils, monocytes, and T cells. J. Exp. Med. 192(7), 1069-1074 (2000).

7. Kahlenberg, J.M., Carmona-Rivera, C., Smith, C.K., et al. Neutrophil extracellular trap-associated protein activation of the NLRP3 inflammasome is enhanced in lupus macrophages. J. Immunol. 190(3), 1217-1226 (2013).

8. Izumi, M., Miyaza, H., Kamakura, T., et al. Blasticidin S-resistance gene (bsr): A novel selectable marker for mammalian cells. Exp. Cell Res. 197(2), 229-233 (1991).

9. Koziel, J., Bryzek, D., Sroka, A., et al. Citrullination alters immunomodulatory function of LL-37 essential for prevention of endotoxin-induced spesis. J. Immunol. 192(11), 5363-5372 (2014).