title: The role of TREM-2 in internalization and intracellular survival of Brucella abortus in murine macrophages.
abstract: Triggering receptor expressed on myeloid cells-2 (TREM-2) is a cell surface receptor primarily expressed on macrophages and dendritic cells. TREM-2 functions as a phagocytic receptor for bacteria as well as an inhibitor of Toll like receptors (TLR) induced inflammatory cytokines. However, the role of TREM-2 in Brucella intracellular growth remains unknown. To investigate whether TREM-2 is involved in Brucella intracellular survival, we chose bone marrow derived macrophages (BMDMs), in which TREM-2 is stably expressed, as cell model. Colony formation Units (CFUs) assay suggests that TREM-2 is involved in the internalization of Brucella abortus (B. abortus) by macrophages, while silencing of TREM-2 decreases intracellular survival of B. abortus. To further study the underlying mechanisms of TREM-2-mediated bacterial intracellular survival, we examined the activation of B. abortus-infected macrophages through determining the kinetics of activation of the three MAPKs, including ERK, JNK and p38, and measuring TNFα production in response to lipopolysaccharide (LPS) of Brucella (BrLPS) or B. abortus stimulation. Our data show that TREM-2 deficiency promotes activation of Brucella-infected macrophages. Moreover, our data also demonstrate that macrophage activation promotes killing of Brucella by enhancing nitric oxygen (NO), but not reactive oxygen species (ROS) production, macrophage apoptosis or cellular death. Taken together, these findings provide a novel interpretation of Brucella intracellular growth through inhibition of NO production produced by TREM-2-mediated activated macrophages.
authors.affiliation: Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, Jilin University, Changchun 130062, People's Republic of China.
authors.forename: Pan
authors.initials: P
authors.lastname: Wei
authors.affiliation: Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, Jilin University, Changchun 130062, People's Republic of China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Lu
authors.affiliation: Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, Jilin University, Changchun 130062, People's Republic of China.
authors.forename: Guimei
authors.initials: G
authors.lastname: Cui
authors.affiliation: Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, Jilin University, Changchun 130062, People's Republic of China.
authors.forename: Zhenhong
authors.initials: Z
authors.lastname: Guan
authors.affiliation: Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, Jilin University, Changchun 130062, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.affiliation: College of Veterinary Medicine, Jilin University, Changchun, People's Republic of China.
authors.forename: Changjiang
authors.initials: C
authors.lastname: Sun
authors.affiliation: Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, Jilin University, Changchun 130062, People's Republic of China.
authors.forename: Wanchun
authors.initials: W
authors.lastname: Sun
authors.affiliation: Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, Jilin University, Changchun 130062, People's Republic of China. Electronic address: Qishengpeng@yahoo.com.
authors.forename: Qisheng
authors.initials: Q
authors.lastname: Peng
mesh_terms: D000818:Animals; D002003:Brucella abortus / Q000502:physiology*; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000502:physiology*; D008262:Macrophage Activation / Q000502:physiology; D008264:Macrophages / Q000378:metabolism* / Q000382:microbiology*; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D017382:Reactive Oxygen Species; D011971:Receptors, Immunologic / Q000235:genetics / Q000378:metabolism*
chemical_list: D016207:Cytokines; D008562:Membrane Glycoproteins; D017382:Reactive Oxygen Species; D011971:Receptors, Immunologic; C498716:Trem2 protein, mouse; D009569:Nitric Oxide
keywords: Brucella abortus; Macrophage; NO; TREM-2