Impaired expression of α-defensin antimicrobial peptides and overproduction the proinflammatory cytokine IL-1β have been associated with inflammatory bowel disease. In this study, we examine interactions between α-defensins role defensin deficiency in pathogenesis It was found that matrix metalloproteinase-7-deficient (MMP-7−/−) mice, which produce procryptdins but not mature ...

Aim. IgA nephropathy (IgAN) is the most common form of glomerulonephritis. Recent genome-wide association study (GWAS) suggested that DEFA locus (which encodes α-defensins) may play a key role in IgAN. Methods. The levels of α-defensins in 169 IgAN patients and 83 healthy controls were tested by ELISA. Results. We observed that α-defensins human neutrophil peptides 1-3 (HNP1-3) in IgAN patients...

High viral tolerance coupled with an extraordinary regulation of the immune response makes bats a great model to study host-pathogen evolution. Although many immune-related gene gains and losses have been previously reported in bats, important families such as antimicrobial peptides (AMPs) remain understudied. We built exhaustive bioinformatic pipeline targeting major defensins cathelicidins ex...

Human α and β-defensins are cationic antimicrobial peptides characterized by three disulfide bonds with a triple stranded β-sheet motif. It is presumed that interaction with the bacterial cell surface and membrane permeabilization by defensins is an important step in the killing process. In this study, we have compared interactions of three human α-defensins HNP3, HNP4, HD5 and human β-defensin...

Alpha-defensins are antibiotic peptides that act as natural inhibitors of HIV-1 infection. However, the mechanisms of such inhibition are still unclear. Here we demonstrate that α-defensins block the earliest steps in the viral infectious cycle, as documented using an HIV-1 envelope-mediated cell fusion assay. A broad-spectrum inhibitory activity was observed on primary and laboratoryadapted HI...

Hepatitis C virus (HCV) is the major etiological agent of human non-A and non-B hepatitis, affecting around 180 million people worldwide. Defensins, small cysteine-rich cationic peptides, are shown to have potent antibacterial, antiviral, and antifungal properties. Defensins can be found in both normal and microbial infected patients, at variable concentrations. Notably, viral infections are of...

α-defensins are abundant antimicrobial peptides with broad, potent antibacterial, antifungal, and antiviral activities in vitro. Although their contribution to host defense against bacteria in vivo has been demonstrated, comparable studies of their antiviral activity in vivo are lacking. Using a mouse model deficient in activated α-defensins in the small intestine, we show that Paneth cell α-de...

Mammalian α-defensins contribute to innate immunity by exerting antimicrobial activity against various pathogens. To perform structural and functional analysis of α-defensins, large amounts of α-defensins are essential. Although many expression systems for the production of recombinant α-defensins have been developed, attempts to obtain large amounts of α-defensins have been only moderately suc...

The small intestinal epithelium produces numerous antimicrobial peptides and proteins, including abundant enteric α-defensins. Although they most commonly function as potent antivirals in cell culture, enteric α-defensins have also been shown to enhance some viral infections in vitro. Efforts to determine the physiologic relevance of enhanced infection have been limited by the absence of a suit...

Antimicrobial peptides are major effectors of innate immunity of multicellular organisms including humans and play a critical role in host defense, and their importance is widely recognized. The epithelium of the intestine is the largest surface area exposed to the outer environment, including pathogens, toxins and foods. The Paneth cell lineage of intestinal epithelial cells produces and secre...