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Updated: Feb 7, 2026

Co-culture Models of Pseudomonas aeruginosa Biofilms Grown on Live Human Airway Cells
Published on: October 6, 2010
Effects of ALA-PDT on biofilm structure, virulence factor secretion, and QS in Pseudomonas aeruginosa
Yang Tan1, Qionghui Cheng1, Hang Yang1
1Department of Dermatology, Daping Hospital, The Army Medical University, Chongqing 400042, China.
Aim:
To investigate the effects of ALA-PDT on biofilm structure, virulence factor secretion, and quorum sensing (QS) in Pseudomonas aeruginosa.
Materials And Methods:
We used confocal laser scanning microscopy (CLSM), an XTT assay, scanning electron microscopy (SEM), a virulence factor assay and qRT-PCR in this study.
Results:
The XTT assay showed that ALA-PDT significantly inhibited the growth of planktonic P. aeruginosa. CLSM and SEM showed that ALA-PDT destroyed both bacterial and biofilm structures. The virulence factor assay showed that pyocyanin and elastase secretion were significantly inhibited in the ALA-PDT groups. qRT-PCR assays demonstrated that ALA-PDT significantly reduced the mRNA expression of QS-related genes.
Conclusion:
ALA-PDT kills planktonic and viable biofilm-associated P. aeruginosa cells, destroys biofilm structures, reduces virulence factor secretion and affects QS system gene expression.
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