PMID- 27872207 OWN - NLM STAT- MEDLINE DCOM- 20170808 LR - 20181113 IS - 1550-6606 (Electronic) IS - 0022-1767 (Print) IS - 0022-1767 (Linking) VI - 198 IP - 1 DP - 2017 Jan 1 TI - Myeloid-Specific Gene Deletion of Protein Phosphatase 2A Magnifies MyD88- and TRIF-Dependent Inflammation following Endotoxin Challenge. PG - 404-416 AB - Protein phosphatase 2A (PP2A) is a member of the intracellular serine/threonine phosphatases. Innate immune cell activation triggered by pathogen-associated molecular patterns is mediated by various protein kinases, and PP2A plays a counter-regulatory role by deactivating these kinases. In this study, we generated a conditional knockout of the alpha isoform of the catalytic subunit of PP2A (PP2ACalpha). After crossing with myeloid-specific cre-expressing mice, effective gene knockout was achieved in various myeloid cells. The myeloid-specific knockout mice (lyM-PP2A(fl/fl)) showed higher mortality in response to endotoxin challenge and bacterial infection. Upon LPS challenge, serum levels of TNF-alpha, KC, IL-6, and IL-10 were significantly increased in lyM-PP2A(fl/fl) mice, and increased phosphorylation was observed in MAPK pathways (p38, ERK, JNK) and the NF-kappaB pathway (IKKalpha/beta, NF-kappaB p65) in bone marrow-derived macrophages (BMDMs) from knockout mice. Heightened NF-kappaB activation was not associated with degradation of IkappaBalpha; instead, enhanced phosphorylation of the NF-kappaB p65 subunit and p38 phosphorylation-mediated TNF-alpha mRNA stabilization appear to contribute to the increased TNF-alpha expression. In addition, increased IL-10 expression appears to be due to PP2ACalpha-knockout-induced IKKalpha/beta hyperactivation. Microarray experiments indicated that the Toll/IL-1R domain-containing adaptor inducing IFN-beta/ TNFR-associated factor 3 pathway was highly upregulated in LPS-treated PP2ACalpha-knockout BMDMs, and knockout BMDMs had elevated IFN-alpha/beta production compared with control BMDMs. Serum IFN-beta levels from PP2ACalpha-knockout mice treated with LPS were also greater than those in controls. Thus, we demonstrate that PP2A plays an important role in regulating inflammation and survival in the setting of septic insult by targeting MyD88- and Toll/IL-1R domain-containing adaptor inducing IFN-beta-dependent pathways. CI - Copyright (c) 2016 by The American Association of Immunologists, Inc. FAU - Sun, Lei AU - Sun L AUID- ORCID: 0000-0002-7804-0876 AD - Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109; leisun@med.umich.edu. FAU - Pham, Tiffany T AU - Pham TT AUID- ORCID: 0000-0003-2057-3204 AD - Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109. FAU - Cornell, Timothy T AU - Cornell TT AUID- ORCID: 0000-0001-5806-7062 AD - Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109. FAU - McDonough, Kelli L AU - McDonough KL AD - Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109. FAU - McHugh, Walker M AU - McHugh WM AUID- ORCID: 0000-0003-3194-8833 AD - Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109. FAU - Blatt, Neal B AU - Blatt NB AD - Division of Pediatric Nephrology, Department of Pediatrics and Communicable Diseases, C.S. Mott Children's Hospital, University of Michigan Medical School, Ann Arbor, MI 48109; and. FAU - Dahmer, Mary K AU - Dahmer MK AUID- ORCID: 0000-0001-7329-1943 AD - Division of Critical Care Medicine, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109. FAU - Shanley, Thomas P AU - Shanley TP AD - Department of Pediatrics, Lurie Children's Hospital of Chicago, Feinberg School of Medicine, Northwestern University, Evanston, IL 60611. LA - eng GR - K08 HD062142/HD/NICHD NIH HHS/United States GR - R01 GM066839/GM/NIGMS NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural PT - Research Support, Non-U.S. Gov't DEP - 20161121 PL - United States TA - J Immunol JT - Journal of immunology (Baltimore, Md. : 1950) JID - 2985117R RN - 0 (Adaptor Proteins, Vesicular Transport) RN - 0 (Endotoxins) RN - 0 (Myd88 protein, mouse) RN - 0 (Myeloid Differentiation Factor 88) RN - 0 (TICAM-1 protein, mouse) RN - EC 3.1.3.16 (Ppm1a protein, mouse) RN - EC 3.1.3.16 (Protein Phosphatase 2C) SB - IM MH - Adaptor Proteins, Vesicular Transport/*immunology MH - Animals MH - Blotting, Western MH - Disease Models, Animal MH - Endotoxins/immunology MH - Escherichia coli Infections/immunology MH - Immunity, Innate MH - Immunoprecipitation MH - Inflammation/immunology MH - Macrophages/*immunology MH - Mice MH - Mice, Knockout MH - Myeloid Cells/immunology MH - Myeloid Differentiation Factor 88/*immunology MH - Oligonucleotide Array Sequence Analysis MH - Polymerase Chain Reaction MH - Protein Phosphatase 2C/deficiency/*metabolism MH - Sepsis/immunology MH - Signal Transduction/*immunology MH - Transcriptome PMC - PMC5173401 MID - NIHMS825327 EDAT- 2016/11/23 06:00 MHDA- 2017/08/09 06:00 PMCR- 2018/01/01 CRDT- 2016/11/23 06:00 PHST- 2016/02/05 00:00 [received] PHST- 2016/10/21 00:00 [accepted] PHST- 2016/11/23 06:00 [pubmed] PHST- 2017/08/09 06:00 [medline] PHST- 2016/11/23 06:00 [entrez] PHST- 2018/01/01 00:00 [pmc-release] AID - jimmunol.1600221 [pii] AID - 10.4049/jimmunol.1600221 [doi] PST - ppublish SO - J Immunol. 2017 Jan 1;198(1):404-416. doi: 10.4049/jimmunol.1600221. Epub 2016 Nov 21.