This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Martinez, L. R.
Right arrow Articles by Casadevall, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Martinez, L. R.
Right arrow Articles by Casadevall, A.

 Previous Article  |  Next Article 

Infection and Immunity, November 2006, p. 6118-6123, Vol. 74, No. 11
0019-9567/06/$08.00+0     doi:10.1128/IAI.00995-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Cryptococcus neoformans Cells in Biofilms Are Less Susceptible than Planktonic Cells to Antimicrobial Molecules Produced by the Innate Immune System

Luis R. Martinez and Arturo Casadevall*

Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461

Received 22 June 2006/ Returned for modification 24 July 2006/ Accepted 3 August 2006

The human pathogenic fungus Cryptococcus neoformans can form biofilms on polystyrene plates and medical devices in a process that requires capsular polysaccharide release. Although biofilms are known to be less susceptible to antimicrobial drugs, little is known about their susceptibility to antimicrobial molecules produced by the innate immune system. In this study, we investigated the susceptibility of C. neoformans cells in biofilm and planktonic states to oxidative and nonoxidative antimicrobial molecules produced by phagocytic cells. The effects of various immune effector molecules on the fungal mass, metabolic activity, and architecture of C. neoformans biofilms were measured by colony counts, 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide reduction, and confocal microscopy, respectively. Biofilms were more resistant than planktonic cells to oxidative stress but remained vulnerable to cationic antimicrobial peptides. However, melanized biofilms were significantly less susceptible to antimicrobial peptides than nonmelanized biofilms. These results suggest that the biofilm phenotype increases resistance against host immune mechanisms, a phenomenon that could contribute to the ability of biofilm-forming microbes to establish persistent infections.

* Corresponding author. Mailing address: Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461. Phone: (718) 430-2215. Fax: (718) 430-8968. E-mail: casadeva{at}aecom.yu.edu.

Editor: J. L. Flynn

Infection and Immunity, November 2006, p. 6118-6123, Vol. 74, No. 11
0019-9567/06/$08.00+0     doi:10.1128/IAI.00995-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Robertson, E. J., Casadevall, A. (2009). Antibody-Mediated Immobilization of Cryptococcus neoformans Promotes Biofilm Formation. Appl. Environ. Microbiol. 75: 2528-2533 [Abstract] [Full Text]  
  • Martinez, L. R., Casadevall, A. (2007). Cryptococcus neoformans Biofilm Formation Depends on Surface Support and Carbon Source and Reduces Fungal Cell Susceptibility to Heat, Cold, and UV Light. Appl. Environ. Microbiol. 73: 4592-4601 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»