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The epidermal mucus layer on the skin of fish consists of many antimicrobial agents that offer a primary line of defense against invasive pathogens from the encompassing setting.  The mucus contains many factors such as antimicrobial peptides (AMPs), lysozyme, lectins, complement, transferrin, interferon, pentraxins, natural antibodies, protease, etc that provide innate immunity.  Many AMPs are reported in fishes together with hepcidins, defensins, cathelicidins, histone-derived peptides and piscidins having board antimicrobial spectrum. Antimicrobial peptides are extraordinarily enticing candidates as therapeutic agents because of their wide spectrum of antimicrobial activity and mechanism of action that differs from that of small-molecule antibiotics. This review summarizes the potential use of mucus as in vivo antimicrobial agent.

Epidermal mucus, antimicrobial peptides, skin, secretion

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