PURPOSE Functions of antimicrobial peptidoglycan recognition proteins (Pglyrp1-4) at the ocular surface are poorly understood. Earlier, we reported an antibacterial role for Pglyrp-1 in Pseudomonas aeruginosa keratitis. Here we investigated functions of three other related genes Pglyrp-2, -3 and -4 in a mouse model of P. aeruginosa keratitis. METHODS Wild type (WT) and each of the Pglyrp-null...

PURPOSE Defensins are naturally occurring antimicrobial peptides. Recently the authors published evidence of defensin production by the human ocular surface. A study was undertaken to look for intraocular defensins that may account for unexplained antimicrobial activity of intraocular fluids. METHODS Reverse transcription-polymerase chain reaction (RT-PCR) was performed on human postmortem ci...

We examined the activity of defensins, cysteine-rich cationic peptides that are abundant in the cytoplasmic granules of human and rabbit granulocytes, against various tumor targets. The three human defensins, HNP-1, HNP-2, and HNP-3, lysed human and murine targets in chromium release and dye exclusion assays. Defensin-mediated tumor cell lysis was concentration-dependent, inhibited by serum, an...

CD91 is a scavenger receptor expressed by different immune cells and its ligands defensins have been demonstrated to contribute to immune responses against infections and tumours. We previously demonstrated that CD91 is expressed on human monocyte-derived dendritic cells (moDCs) and that human defensins stimulate in vitro the activation of these cells. In this study, we observed that CD91 is ex...

Defensins represent an evolutionary ancient family of antimicrobial peptides that play diverse roles in human health and disease. Defensins are cationic cysteine-containing multifunctional peptides predominantly expressed by epithelial cells or neutrophils. Defensins play a key role in host innate immune responses to infection and, in addition to their classically described role as antimicrobia...

We developed a kinetic, 96-well turbidimetric procedure that is capable of testing the antimicrobial properties of six human -defensins concurrently on a single microplate. The defensins were prepared by solidphase peptide synthesis and tested against gram-positive bacteria (Staphylococcus aureus and Bacillus cereus) and gram-negative bacteria (Enterobacter aerogenes and Escherichia coli). Anal...

Antimicrobial peptides are a potent group of defense active molecules that have been utilized in developing resistance against a multitude of plant pathogens. Floral defensins constitute a group of cysteine-rich peptides showing potent growth inhibition of pathogenic filamentous fungi especially Fusarium oxysporum in vitro. Full length genes coding for two Petunia floral defensins, PhDef1 and P...

Defensins are small cationic peptides that are crucial components of innate immunity, serving as both antimicrobial agents and chemoattractant molecules. The specific mechanism of antimicrobial activity involves permeabilization of bacterial membranes. It has been postulated that individual monomers oligomerize to form a pore through anionic membranes, although the evidence is only indirect. He...

Bovine alveolar macrophages (BAM) were examined for the expression of beta-defensins and to determine whether their expression could be upregulated by bacterial lipopolysaccharide (LPS), as observed with beta-defensins expressed in bovine tracheal epithelial cells. Four beta-defensins were expressed constitutively in BAM, with bovine neutrophil beta-defensin (BNBD)-4 and BNBD-5 being the most p...

The defensins knowledgebase is a manually curated database and information source focused on the defensin family of antimicrobial peptides. The current version of the database holds a comprehensive collection of over 350 defensin records each containing sequence, structure and activity information. A web-based interface provides access to the information and allows for text-based searching on t...