Defensin alpha4 (Neutrophil Defensin 4, Defensin, alpha 4, HNP-4, HP-4, DEFA4, DEF4, alpha-Defensin 4)

Human neutrophil alpha-defensins (also designated HNPs) are small, cationic,cysteine-rich antimicrobial proteins that play important roles in innate immunity against infectious microbes such as bacteria, fungi and enveloped viruses. Alpha-defensins are synthesized as inactive precursors and are activated by proteolytic cleavage by MMP-7. Paneth cells in small intestinal crypts secrete the alpha-defensins, which are also termed cryptidins in mice.The cryptidin-4 gene is unique among the Paneth cell alpha defensins in that it is inactive in the duodenum, but expressed at maximal levels in the distal...