Beta-defensin 2, Human, mAb HB12C9

Monoclonal antibody HB12G9 recognized human beta defensin-2 (HBD2). hBD-2 is a cysteine-rich cationic 41 amino acid antimicrobial peptide of 4-5 kDa. Human BD-2 is produced by epithelial cells upon stimulus by lipopolysaccharides and proinflammatory cytokines TNFα and IL1β. Contact of keratinocytes with gram-negative bacteria results in rapid induction of hBD-2 protein. hBD-2 has been described as a dynamic component of the local epithelial defense system of the skin, intestinal and respiratory tract, where it functions by protecting surfaces from infection. Its local expression has been associated with skin lesions like psoriasis as well as infected lung epithelia of patients with cystic fibrosis. Furthermore, in inflammatory bowel disease (IBD), expression of hBD-2 is increased in patients with IBD compared to healthy persons. The NF-kB pathway has been recognized as a key component in the induction of hBD-2 expression, however, other studies have observed induction mediated by the mitogen-activated protein kinase (MAPK) pathways. Thus, increased expression of hBD-2 in epithelial cells is associated with the proinflammatory response. This is supported by the finding that the anti-inflammatory cytokines IL-10 and IL-13 downregulate the synthesis of hBD-2 in atopic dermatitis.