Beta-defensin 104B (DEFB104B)

Beta-defensin 104B is a small, cationic, cysteine-rich antimicrobial peptide in the beta-defensin family, encoded by the DEFB104B gene, which is part of a duplicated cluster on chromosome 8p23[1][4]. Defensins including beta-defensin 104B are primarily expressed in neutrophils and epithelial cells, where they serve as critical effectors of the innate immune system due to their ability to disrupt the membranes of bacteria, fungi, and some viruses, leading to microbe cell death[3][4][8]. DEFB104B is structurally characterized by a conserved β-sheet stabilized by three intramolecular disulfide bonds. It exhibits direct antimicrobial and cytotoxic activity, and can act synergistically with other innate immune molecules such as lysozyme[4]. Expression of beta-defensins is often inducible in response to microbial infection or inflammatory signals, contributing to mucosal barrier defense and immune modulation[6][8]. Beta-defensin 104B, together with its paralog beta-defensin 104A, may play roles in lung inflammatory diseases and rare genetic syndromes, though its exact pathophysiological impact is not fully defined[4][2]. There is increasing research interest in beta-defensins as templates for novel antimicrobial agents, but no approved drugs directly target this molecule at present[3].

Other names

DEFB104ABeta-defensin 104DEFB104DEFB4BD-4DEFB-4hBD-4Beta-defensin 4Defensin, beta 104beta-defensin 104beta-defensin 4defensin, beta 104

Disrupts microbial cell membranes leading to cell lysis. Synergistic action with lysozyme and other defensins (e.g., DEFB103) to enhance antimicrobial effects. Involvement in modulation of the immune response and mucosal barrier function.