Beta-defensin 2 (hBD-2)

Beta-defensin 2 (hBD-2) is a cationic, cysteine-rich antimicrobial peptide encoded by the DEFB4 gene in humans[1][7]. It consists of 41–64 amino acids (depending on precursor versus mature), forms star-shaped dimers or higher-order oligomers, and exhibits strong antimicrobial properties against Gram-negative bacteria, Candida species, and some viruses, but little activity against Gram-positive bacteria unless synergistically combined with other peptides[1][2][4]. hBD-2 is produced by epithelial cells (skin, airway, gastrointestinal tract) in response to infection or proinflammatory cytokines like TNF-α and IL-1β[1][5]. Its primary mechanism involves disruption of microbial membranes via electrostatic interactions. Beyond direct microbicidal effects, hBD-2 modulates immune responses, recruits leukocytes, and promotes wound healing and angiogenesis[3][6]. Its role in mucosal, skin, and respiratory innate defense is well established, and altered expression has been implicated in diseases such as psoriasis and cystic fibrosis[5]. hBD-2 is being explored as a potential therapeutic agent and biomarker but presents challenges concerning stability, delivery, and immunomodulatory balance[6].

Other names

Beta-defensin-2BD-2Skin-antimicrobial peptide 1 (SAP1)DEFB4DEFB4A proteinhuman beta defensin 2hBD2

Membrane permeabilization: disrupts microbial membranes via electrostatic charge-based interactions Immunomodulation: chemoattractant activity, regulation of cytokine responses Potential pro-angiogenic effect in wound healing[3][6]