Legionella pneumophila (Lp) is the pathogen responsible for Legionnaires disease. Lp invades and survives in human macrophages to form an intracellular compartment, called the Legionella containing vacuole (LCV). Within the LCV, Lp avoids degradation and replicates, before killing its host and releasing its virulent progeny. Lp is pleomorphic, exhibiting a combination of short rod phenotypes and filaments. Filamentous Lp has been reported in patient samples, but current studies of Lp virulence are exclusively focused on rods. Our results show that filamentous Lp can invade and replicate in human and murine macrophages. Filaments are phagocytosed gradually into tubular phagocytic cups. Interestingly, the formation of the LCV starts at this stage of phagocytosis, and LCV markers were detected before the sealing of the phagosome occurred. We present evidence that the filamentous morphology acts cooperatively with Lp effectors to subvert the microbicidal activities of the macrophage, contributing to the survival of Lp.
Identifer | oai:union.ndltd.org:TORONTO/oai:tspace.library.utoronto.ca:1807/33217 |
Date | 20 November 2012 |
Creators | Gigliozzi, Darren |
Contributors | Terebiznik, Mauricio |
Source Sets | University of Toronto |
Language | en_ca |
Detected Language | English |
Type | Thesis |
Page generated in 0.0015 seconds