Please use this identifier to cite or link to this item: http://hdl.handle.net/20.500.11889/4103
Title: Biofilm-derived Legionella pneumophila evades the innate immune response in macrophages
Authors: Abu Khweek, Arwa
Davila, Natalia Sofia Fernandez
Caution, Kyle
Akhter, Anwari
Abdulrahman, Basant A.
Tazi, Mia
Hassan, Hoda
Novotny, Laura A.
Bakaletz, Lauren O.
Amer, Amal O.
Keywords: Legionella pneumophila
Immunology
Biofilms
Natural immunity
Issue Date: 27-Mar-2013
Abstract: Legionella pneumophila, the causative agent of Legionnaire’s disease, replicates in human alveolar macrophages to establish infection. There is no human-to-human transmission and the main source of infection is L. pneumophila biofilms established in air conditioners, water fountains, and hospital equipments. The biofilm structure provides protection to the organism from disinfectants and antibacterial agents. L. pneumophila infection in humans is characterized by a subtle initial immune response, giving time for the organism to establish infection before the patient succumbs to pneumonia. Planktonic L. pneumophila elicits a strong immune response in murine, but not in human macrophages enabling control of the infection. Interactions between planktonic L. pneumophila and murine or human macrophages have been studied for years, yet the interface between biofilm-derived L. pneumophila and macrophages has not been explored. Here, we demonstrate that biofilm-derived L. pneumophila replicates significantly more in murine macrophages than planktonic bacteria. In contrast to planktonic L. pneumophila, biofilm-derived L. pneumophila lacks flagellin expression, do not activate caspase-1 or -7 and trigger less cell death. In addition, while planktonic L. pneumophila is promptly delivered to lysosomes for degradation, most biofilm-derived bacteria were enclosed in a vacuole that did not fuse with lysosomes in murine macrophages. This study advances our understanding of the innate immune response to biofilm-derived L. pneumophila and closely reproduces the natural mode of infection in human
Description: Authors include Natalia S. Fernández Dávila, Kyle Caution, Anwari Akhter, Basant A. Abdulrahman, Mia Tazi, Hoda Hassan, Laura A. Novotny, Lauren O. Bakaletz and Amal O. Amer
URI: http://hdl.handle.net/20.500.11889/4103
Appears in Collections:Fulltext Publications

Files in This Item:
File Description SizeFormat 
fcimb-03-00018.pdf2.05 MBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.