Prostate specific antigen enhances the innate defence of prostatic epithelium against Escherichia coli infection.

Background: This study investigated whether the increase in serum prostate specific antigen (PSA) typically seen during male urinary tract infection (UTI) is incidental or reflects an innate defence mechanism of the prostate. The protective roles of the whey-acid-motif-4-disulphide core (WFDC) proteins, secretory leukoproteinase inhibitor (SLPI) and WFDC2, in the prostate were also examined.

Methods: UTI recurrence was assessed retrospectively in men following initial UTI by patient interview.

Tolerance of bacteriuria after urinary diversion is linked to antimicrobial peptide activity.

Objectives: To compare the cationic antimicrobial peptide gene expression profiles and urinary cationic antimicrobial activities of patients after urinary diversion according to their urinary tract infection (UTI) status. Ileal conduit urinary diversion joins the bacterial-tolerant ileal epithelium and intolerant urothelium. After this procedure, one quarter of patients develop repeated symptomatic UTIs.

Expression and functional analyses of liver expressed antimicrobial peptide-2 (LEAP-2) variant forms in human tissues.

The antimicrobial peptide Liver Expressed Antimicrobial Peptide-2 (LEAP-2) is proposed to function as part of the vertebrate innate immune system. However, the highly conserved nature of the LEAP-2 peptide primary structure among vertebrates suggests more fundamental physiological roles. RT-PCR analyses confirmed expression of LEAP-2 mRNA variants in human gastro-intestinal (GI) epithelial tissues and THP-1 monocytes.

The interaction of the antimicrobial peptide cLEAP-2 and the bacterial membrane.

Chicken Liver Expressed Antimicrobial Peptide-2 (cLEAP-2) is known to have killing activities against Salmonella spp., but the mechanism by which killing occurs remains to be elucidated. The ability of cLEAP-2 to disrupt the outer membrane of several Salmonella spp.

Maintaining a sterile urinary tract: the role of antimicrobial peptides.

Purpose: The normally sterile urinary tract is constantly challenged by microbial invasion leading to a high prevalence of isolated, recurrent and catheter associated urinary tract infection. The continuous emergence of bacterial resistance following overuse of traditional antibiotics requires the urgent development of alternative treatment strategies. The involvement of innate immune mechanisms in host defense is an emerging field of microbiological research with recent work focusing on the urinary tract.

The chicken host peptides, gallinacins 4, 7, and 9 have antimicrobial activity against Salmonella serovars.

The gallinacin genes clustered on chromosome 3 of the chicken (Gallus gallus domesticus) genome encode a group of cationic antimicrobial peptides characteristic of the beta-defensins. In this study, gallinacins 4, 7, and 9, all predicted to contain the conserved pattern of cysteines typical of beta-defensins but differing in their charge and hydrophobicity, were characterised for their in vivo gene expression patterns and in vitro antimicrobial activities against Salmonella serovars. Reverse-transcription PCR analyses of chicken epithelial tissues indicated gallinacin (Gal) 7 expression to be ubiquitous while Gal 4 and Gal 9 expression appeared localized to specific epithelial tissues including the ovary, trachea, and lung, respectively.

The novel avian protein, AWAK, contains multiple domains with homology to protease inhibitory modules.

We report the purification of a 3.5kDa peptide with antimicrobial activity from the mucosa and epithelial cells of chicken intestine. The peptide contains a pattern of cysteines characteristic of a whey acidic protein (WAP) domain and was identified as the carboxy terminal fragment of a novel 767 amino acid avian protein which has a proposed molecular weight of 81kDa.