| Autor: |
Christopher K. E. Bleck, Benoit Zuber, Jacques Dubochet, David Liebl, Andreas Merz, Paul Walther, Gareth Griffiths |
| Rok vydání: |
2008 |
| Předmět: |
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| Zdroj: |
EMC 2008 14th European Microscopy Congress 1–5 September 2008, Aachen, Germany ISBN: 9783540852278 |
| DOI: |
10.1007/978-3-540-85228-5_114 |
| Popis: |
Phagocytosis is the process whereby cells such as macrophages take up particles larger than 0.3 uM. The ingested particle can range from inert material such as carbon or asbestos to live pathogens such as Mycobacterium tuberculosis. After engulfment by the plasma membrane of the phagocytic cell the engulfed particle becomes surrounded by a membrane in a specialized intracellular compartment - the phagosome. This compartment fuses sequentially with early endosomes, late endosomes and lysosomes, a process referred to as phagosome maturation, in which the phagosome acquires acid hydrolases and a low pH that together facilitate pathogen clearance. Actin assembly by phagosomes plays an important role in phagosome maturation. Once internalized into the phagocytic cell M.tuberculosis has evolved the ability to block actin assembly and maturation of phagosome, that facilitates the ability of this pathogen to survive and grow within macrophages. This presentation will focus on two aspects of phagosome biology, in order to emphasize the importance of light microscopy and EM in analyzing the cell biology of phagosomes. In the first part the use of live cell video microscopy will be described in order to reveal striking dynamic process of transient assembly of actin by latex bead phagosomes in GFP-actin expressing mouse macrophages. The second part will address the use of different EM sectioning approaches to visualize different mycobacteria in macrophage phagosomes and will conclude that the best sectioning method to monitor the native structure of free mycobacteria and mycobacteria within phaagosomes is the Cryo EM of Vitrified Sections (CEMOVIS). |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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