Early effects of Staphylococcus aureus biofilm secreted products on inflammatory responses of human epithelial keratinocytes

Journal of Inflammation

Research

Robert Brennan¹  Amy Tankersley¹  Melissa Bebak²  Mark Barton Frank² 

[1] Biology Department, University of Central Oklahoma, 100 North University Drive, 73034, Edmond, Oklahoma, USA;Microarray Research Facility, Arthritis and Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA;

关键词: Staphylococcus aureus;    Biofilms;    Keratinocytes;    Inflammation;    Nitric oxide;    Gene expression microarray;   

DOI  :  10.1186/1476-9255-11-17

 received in 2013-07-18, accepted in 2014-05-30,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundChronic wounds such as diabetic foot ulcers, pressure ulcers, and venous leg ulcers contribute to a considerable amount of mortality in the U.S. annually. The inability of these wounds to heal has now been associated with the presence of microbial biofilms. The aim of this study was to determine if products secreted by S. aureus biofilms play an active role in chronic wounds by promoting inflammation, which is a hallmark of chronic wounds.MethodsIn vitro experiments were conducted to examine changes in gene expression profiles and inflammatory response of human epithelial keratinocytes (HEKa) exposed to products secreted by S. aureus grown in biofilms or products secreted by S. aureus grown planktonically.ResultsAfter only two hours of exposure, gene expression microarray data showed marked differences in inflammatory, apoptotic, and nitric oxide responses between HEKa cells exposed to S. aureus biofilm conditioned media (BCM) and HEKa cells exposed to S. aureus planktonic conditioned media (PCM). As early as 4 hours post exposure, ELISA results showed significant increases in IL-6, IL-8, TNFα, and CXCL2 production by HEKa cells exposed to BCM compared to HEKa cells exposed to PCM or controls. Nitric oxide assay data also showed significant increases in nitric oxide production by HEKa cells treated with BCM compared to HEKa cells treated with PCM, or controls.ConclusionsTaken together, these results support and extend previous findings that indicate products secreted by S. aureus biofilms directly contribute to the chronic inflammation associated with chronic wounds.

【 授权许可】

Unknown   
© Tankersley et al.; licensee BioMed Central Ltd. 2014. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited.