Beta-defensin 3 is a member of the defensin family. Defensin family is comprised by microbicidal and cytotoxic peptides made by neutrophils. Members of the beta-defensin 3 family are highly similar in protein sequence. Beta-defensin 3 shows antimicrobial activity against Gram-positive bacteria S.aureus and S.pyogenes, Gram-negative bacteria P.aeruginosa and E.coli and the yeast C.albicans. Beta-defensin 3 is abundantly expressed in skin and tonsils, and to a lesser extent in trachea, uterus, kidney, thymus, adenoid, pharynx and tongue. It is also expressed in salivary gland, bone marrow, colon, stomach, polyp and larynx. However, in small intestine, it cannot be detected. Defensin has broad spectrum antimicrobial activity and may play an important role in innate epithelial defense. Beta-defensin 3 kills multiresistant S.aureus and vancomycin-resistent E.faecium. It has no significant hemolytic activity.