The role of triggering receptor expressed on myeloid cells-2 in inflammation Doctoral Thesis at the Medical University of Vienna for obtaining the academic degree Doctor of Philosophy (PhD) submitted by Maga. Riem Gawish Supervisor: Univ. Prof. Dr. Sylvia Knapp, PhD Laboratory of Infection Biology, Dept. of Medicine 1, Medical University Vienna Center for Molecular Medicine of the Austrian Academy of Sciences Währinger Gürtel 18-20, 1090 Vienna, Austria Vienna, 03/2015 The role of triggering receptor expressed on myeloid cells-2 in inflammation Riem Gawish Table of contents Declaration ................................................................................................................................. 5 List of Figures ............................................................................................................................ 6 List of tables ............................................................................................................................... 8 Abstract ...................................................................................................................................... 9 Kurzfassung ................................................................................................................................ 9 Publications arising from this thesis ......................................................................................... 12 Abbreviations (alphabetically ordered) .................................................................................... 13 Acknowledgements .................................................................................................................. 17 1. Introduction ....................................................................................................................... 18 1.1. Innate immunity and Inflammation ............................................................................ 18 1.1.1. Definition and general concepts .......................................................................... 18 1.1.2. Phases of inflammation ....................................................................................... 20 Initiation – Activation of Pattern Recognitions Receptors: ................................ 20 Acute phase response and complement activation:............................................. 22 Resolution of inflammation: ............................................................................... 25 1.1.3. Innate immune cells – key players of inflammation ........................................... 26 Macrophages: ...................................................................................................... 27 Neutrophils: ......................................................................................................... 28 1.2. Regulation of TLR-mediated inflammation ............................................................... 29 1.2.1. Soluble and decoy factors ................................................................................... 30 1.2.2. Disruption of adaptor complexes ........................................................................ 30 1.2.3. Degradation of signal transducers ....................................................................... 31 1.2.4. Transcriptional regulation ................................................................................... 31 1.3. Inflammatory diseases ................................................................................................ 32 1.3.1. Sepsis – Terms and definitions ........................................................................... 32 1.3.2. Peritonitis ............................................................................................................ 33 2 The role of triggering receptor expressed on myeloid cells-2 in inflammation Riem Gawish 1.3.3. Innate immunity during peritonitis ..................................................................... 34 1.3.4. Pneumonia ........................................................................................................... 35 1.3.5. Innate immunity in pneumococcal pneumonia ................................................... 35 1.4. Triggering receptor expressed on myeloid cells-2 ..................................................... 36 1.4.1. Lessons from the Nasu-Hakola disease .............................................................. 36 1.4.2. TREM-2/DAP12 signaling ................................................................................. 37 1.4.3. TREM-2 and the brain ........................................................................................ 39 1.4.4. TREM-2 expression ............................................................................................ 40 1.4.5. TREM-2 and inflammation ................................................................................. 41 1.4.6. TREM-2 as a phagocytic receptor ...................................................................... 42 1.4.7. TREM-2 and bone formation .............................................................................. 43 1.5. Aim of the thesis ........................................................................................................ 44 2. Results ............................................................................................................................... 45 2.1. The role of TREM-2 in Gram-negative sepsis ........................................................... 45 List of abbreviations ......................................................................................................... 46 Abstract ............................................................................................................................ 47 Introduction ...................................................................................................................... 48 Materials and Methods ..................................................................................................... 51 Results ............................................................................................................................. 54 Discussion ........................................................................................................................ 63 References ........................................................................................................................ 67 Acknowledgements and Support ...................................................................................... 71 Conflict of interest ............................................................................................................ 71 2.2. TREM-2 and pneumococcal pneumonia .................................................................... 72 Abstract ............................................................................................................................ 73 Author Summary .............................................................................................................. 74 Introduction ...................................................................................................................... 75 Results ............................................................................................................................. 77 3 The role of triggering receptor expressed on myeloid cells-2 in inflammation Riem Gawish Discussion ........................................................................................................................ 92 Materials and Methods ..................................................................................................... 96 Supporting information: ................................................................................................. 104 References ...................................................................................................................... 110 3. Discussion ....................................................................................................................... 115 4. References ....................................................................................................................... 122 Curriculum vitae ..................................................................................................................... 138 Copyright statements .............................................................................................................. 141 4 The role of triggering receptor expressed on myeloid cells-2 in inflammation Riem Gawish Declaration The doctoral candidate, Riem Gawish, conducted her PhD studies under the supervision of Prof. Dr. Sylvia Knapp, PhD at the Department of Medicine 1, Laboratory of Infection Biology, Medical University of Vienna and the Research Center for Molecular Medicine (Ce- M-M-) of the Austrian Academy of Sciences. For the publication “Triggering receptor expressed on myeloid cells-2 fine-tunes inflammatory responses in murine Gram-negative sepsis” included in chapter 2 of this thesis, Riem Gawish performed the majority of experiments, analyzed the data and wrote the manuscript. Sylvia Knapp funded and conceived the project, supervised the work and wrote the manuscript. Rui Martins and Omar Sharif assisted with experimental work and data analysis. Benedikta Böhm and Terije Antari Wimberger assisted with experiments regarding the expression of TREM-2 on macrophages upon LPS challenge for their master thesis under the co-supervision by Riem Gawish and Sylvia