Impaired expression of alpha-defensin antimicrobial peptides and overproduction of the proinflammatory cytokine IL-1beta have been associated with inflammatory bowel disease. In this study, we examine the interactions between alpha-defensins and IL-1beta and the role of defensin deficiency in the pathogenesis of inflammatory bowel disease. It was found that matrix metalloproteinase-7-deficient ...

Human polymorphonuclear leukocytes (PMN) contain three antimicrobial and cytotoxic peptides which belong to a family of mammalian granulocyte peptides named defensins. To determine their potential availability for extracellular microbicidal or cytotoxic events, we quantified the extracellular release of defensins after stimulation of human PMN with phorbol myristate acetate and opsonized zymosa...

Porphyromonas gingivalis produces proteases capable of degrading cytokines, host heme proteins and some antimicrobial peptides. In this study, we show that P. gingivalis culture supernatants fully or partially degrade human neutrophil peptide alpha-defensins and human beta-defensins after 30 min. This observation suggests that proteases from P. gingivalis degrade defensins and this activity cou...

Gingival epithelium produces β-defensins, small cationic peptides, as part of its contribution to the innate host defense against the bacterial challenge that is constantly present in the oral cavity. Besides their functions in healthy gingival tissues, β-defensins are involved in the initiation and progression, as well as restriction of periodontal tissue destruction, by acting as antimicrobia...

Enteric defensins likely play a key role in the management of the human microbiome throughout development. The functional and mechanistic diversity of defensins is much greater than was initially thought. Defensin expression and overall Paneth cell physiology likely plays a key role in the development of colitis and other inflammatory or dysbiotic diseases of the gut. As our understanding of en...

Neutrophils have the capacity to accumulate in high numbers in the lung during infection and inflammation. Because they play an important role in host defence against infection, but may also cause tissue injury, these cells are thought to be involved in the pathogenesis of various inflammatory lung disorders, including chronic bronchitis and chronic obstructive pulmonary disease. Neutrophil pro...

Sepsis is a leading cause of mortality and morbidity in the critical illness. Multiple immune inflammatory processes take part in the pathogenesis of sepsis. Defensins are endogenous antimicrobial peptides with three disulphide bonds created by six cysteine residues. Besides the intrinsic microbicidal properties, defensins are active players which modulate both innate and adaptive immunity agai...

Defensins are antimicrobial peptides (AMPs) and play an important role in both innate and adaptive immune response (Ganz, 2002; Yang et al., 2004). Defensins display broad antimicrobial activities against bacteria, fungi and viruses (Ganz, 2003; Lehrer, 2004; Zanetti, 2004),(Yang et al., 2004). Importantly, they also play a role in inflammation, tissue repair and angiogenesis (Kruse and Kristen...