Format

Send to

Choose Destination
See comment in PubMed Commons below
Br J Ophthalmol. 2006 May;90(5):609-11.

The in vitro activity of selected defensins against an isolate of Pseudomonas in the presence of human tears.

Author information

1
University of Houston, College of Optometry, TX, USA.

Abstract

BACKGROUND/AIMS:

Pseudomonas aeruginosa is a major cause of severe bacterial keratitis and remains a difficult clinical entity to treat successfully with the current arsenal of antimicrobial agents. Defensins are small cationic peptides with broad in vitro antimicrobial activity and are potential ocular therapeutic agents. The authors characterised the in vitro activity of defensins NP-1 and NP-3a against P aeruginosa in the presence of human tears.

METHODS:

A clinical Pseudomonas isolate was grown to mid-log phase, and 1 x 10(6 )colony forming units were exposed to the peptides (200 microg/ml) for up to 2 hours in the presence of varying concentrations (10-70%) of human tears.

RESULTS:

For both peptides in the presence of 10% tears, >3 log units of killing was achieved within 30 minutes. In 70% tears, NP-1 produced >1 log unit of killing at 2 hours, indicating that, although reduced, its activity remained significant. In 20% tears, NP-3a demonstrated 2 log units of killing at 2 hours; however, the antimicrobial activity of this defensin was completely inhibited in the presence of 70% tears.

CONCLUSION:

These in vitro data suggest that while the microbicidal activity of some defensins may be diminished at the ocular surface in vivo, significant activity is still possible with certain peptides.

PMID:
16622092
PMCID:
PMC1857073
DOI:
10.1136/bjo.2005.083428
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center