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Rughetti A, Bharti S, Savai R, Barmpoutsi S, Weigert A, Atre R, Siddiqi F, Sharma R, Khabiya R, Hirani N, Baig MS. Imperative role of adaptor proteins in macrophage toll-like receptor signaling pathways. Future Sci OA 2024; 10:2387961. [PMID: 39248050 PMCID: PMC11385170 DOI: 10.1080/20565623.2024.2387961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 07/30/2024] [Indexed: 09/10/2024] Open
Abstract
Macrophages are integral part of the body's defense against pathogens and serve as vital regulators of inflammation. Adaptor molecules, featuring diverse domains, intricately orchestrate the recruitment and transmission of inflammatory responses through signaling cascades. Key domains involved in macrophage polarization include Toll-like receptors (TLRs), Src Homology2 (SH2) and other small domains, alongside receptor tyrosine kinases, crucial for pathway activation. This review aims to elucidate the enigmatic role of macrophage adaptor molecules in modulating macrophage activation, emphasizing their diverse roles and potential therapeutic and investigative avenues for further exploration.
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Affiliation(s)
- Aurelia Rughetti
- Laboratory of Tumor Immunology & Cell Therapy, Department of Experimental Medicine, Policlinico Umberto I, University of Rome "Sapienza", Rome, Italy
| | - Shreya Bharti
- Department of Biosciences & Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Indore, India
| | - Rajkumar Savai
- Lung Microenvironmental Niche in Cancerogenesis, Institute for Lung Health (ILH), Justus Liebig University, Giessen, D-35390, Germany
- Max Planck Institute for Heart & Lung Research, Member of the German Center for Lung Research (DZL), Member of the Cardio-Pulmonary Institute (CPI), Bad Nauheim, D-61231, Germany
- Institute of Biochemistry, Faculty of Medicine, Goethe University Frankfurt, Frankfurt, D-60590, Germany
| | - Spyridoula Barmpoutsi
- Lung Microenvironmental Niche in Cancerogenesis, Institute for Lung Health (ILH), Justus Liebig University, Giessen, D-35390, Germany
- Max Planck Institute for Heart & Lung Research, Member of the German Center for Lung Research (DZL), Member of the Cardio-Pulmonary Institute (CPI), Bad Nauheim, D-61231, Germany
| | - Andreas Weigert
- Institute of Biochemistry, Faculty of Medicine, Goethe University Frankfurt, Frankfurt, D-60590, Germany
- Frankfurt Cancer Institute (FCI), Goethe University Frankfurt, Frankfurt, D-60323, Germany
| | - Rajat Atre
- Department of Biosciences & Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Indore, India
| | - Faaiza Siddiqi
- Department of Biosciences & Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Indore, India
| | - Rahul Sharma
- Department of Biosciences & Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Indore, India
| | - Rakhi Khabiya
- Department of Biosciences & Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Indore, India
| | - Nik Hirani
- MRC Centre for Inflammation Research, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, EH164TJ, UK
| | - Mirza S Baig
- Department of Biosciences & Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Indore, India
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Xie Y, Xu H, Gu Z. Ge-gen decoction alleviates primary dysmenorrhoea symptoms in a rat model. J OBSTET GYNAECOL 2024; 44:2337691. [PMID: 38594870 DOI: 10.1080/01443615.2024.2337691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 03/25/2024] [Indexed: 04/11/2024]
Abstract
BACKGROUND Existing treatments for primary dysmenorrhoea (PD), such as NSAIDs, impart side effects. Ge-Gen decoction (GGD), a traditional Chinese medicine, has shown promise in treating PD, but its exact mechanisms remain unclear. Here, we aimed to investigate the efficiency of GGD in alleviating PD using a rat model to understand its precise mechanism of action. METHODS We established a rat model of dysmenorrhoea induced by oestradiol and oxytocin. The PD rats were administered GGD or Ibuprofen (positive control) intragastrically once daily for seven consecutive days. Serum levels of prostaglandin E2 (PGE2), prostaglandin F2 alpha (PGF2α), β-endorphin (β-EP), thromboxane B2 (TXB2), 6-keto-prostaglandin F1α (6-keto-PGF1α) were determined using an enzyme-linked immunosorbent assay (ELISA). The expression levels of oestrogen receptor alpha (ERα) and cyclooxygenase-2 (COX-2) in uterine tissue were measured using immunohistochemical assays, and those of phosphorylated and total extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) were assessed using western blot analysis. RESULTS Treatment with GGD significantly reduced writhing behaviour, histopathological scores, and levels of COX-2, PGE2, and PGF2α in the serum of PD rats. Additionally, GGD increased β-EP content and inhibited ERK1/2 activation and ERα expression in uterine tissues. CONCLUSIONS The results of this study suggest that GGD alleviates PD in rats by suppressing the COX-2-mediated release of PGE2 and PGF2α, modulating the ERα/ERK1/2/COX-2 pathway, and increasing β-EP content. These results provide insights into the potential mechanisms of GGD in treating PD and support its further investigation as an alternative therapy for this condition.
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Affiliation(s)
- Yazhen Xie
- Department of Gynaecology, Taicang Traditional Chinese Medicine Hospital, Affiliated to Nanjing University of Chinese Medicine, Taicang, Jiangsu, China
| | - Haifeng Xu
- Department of Anorectal Surgery, Taicang Traditional Chinese Medicine Hospital, Affiliated to Nanjing University of Chinese Medicine, Taicang, Jiangsu, China
| | - Zhijuan Gu
- Department of Gynaecology, Taicang Traditional Chinese Medicine Hospital, Affiliated to Nanjing University of Chinese Medicine, Taicang, Jiangsu, China
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3
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Stocks CJ, Li X, Stow JL. New advances in innate immune endosomal trafficking. Curr Opin Cell Biol 2024; 89:102395. [PMID: 38970837 DOI: 10.1016/j.ceb.2024.102395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 05/28/2024] [Accepted: 06/11/2024] [Indexed: 07/08/2024]
Abstract
The exocytic and endocytic intracellular trafficking pathways in innate immune cells are known for mediating the secretion of key inflammatory mediators or the internalization of growth factors, nutrients, antigens, cell debris, pathogens and even therapeutics, respectively. Inside cells, these pathways are intertwined as an elaborate network that supports the regulation of immune functions. Endosomal membranes host dynamic platforms for molecular complexes that control signaling and inflammatory responses. High content screens, coupled with elegant microscopy across the scale of resolving molecular complexes to tracking live cellular organelles, have been employed to generate the studies highlighted here. With a focus on deactivation of STING, scaffolding by SLC15A4/TASL complexes and macropinosome shrinkage via the chloride channel protein TMEM206, new studies are identifying molecules, molecular interactions and mechanisms for immune regulation throughout endosomal pathways.
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Affiliation(s)
- Claudia J Stocks
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Xichun Li
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Jennifer L Stow
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia.
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Pu Z, Wang W, Xie H, Wang W. Apolipoprotein C3 (ApoC3) facilitates NLRP3 mediated pyroptosis of macrophages through mitochondrial damage by accelerating of the interaction between SCIMP and SYK pathway in acute lung injury. Int Immunopharmacol 2024; 128:111537. [PMID: 38232538 DOI: 10.1016/j.intimp.2024.111537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 12/25/2023] [Accepted: 01/10/2024] [Indexed: 01/19/2024]
Abstract
Respiratory failure caused by severe acute lung injury (ALI) is the main cause of mortality in patients with COVID-19.This study aimed to investigate the effects and underlying biological mechanism of Apolipoprotein C3 (ApoC3) in ALI. To establish an in vivo model, C57BL/6 mice were exposed by lipopolysaccharide (LPS). For the in vitro model, murine bone marrow-derived macrophages (BMDMs) or RAW264.7 cells were stimulated with LPS + adenosine triphosphate (ATP). Serum levels of ApoC3 were found to be upregulated in patients with COVID-19 or pneumonia-induced ALI. Inhibition of ApoC3 reduced lung injury in an ALI model, while overexpression of ApoC3 promoted lung injury. ApoC3 induced mitochondrial damage-mediated pyroptosis in ALI through the activation of the NOD-like receptorprotein 3 (NLRP3) inflammasome. ApoC3 recombinant protein significantly increased SCIMP expression in the lung tissue of mice models with ALI. ApoC3 also facilitated the interaction between the SLP adapter and CSK-interacting membrane protein (SCIMP) protein and Spleen tyrosine kinase (SYK) protein in the ALI model. Moreover, ApoC3 accelerated calcium-dependent reactive oxygen species (ROS) production in the ALI model. The effects of ApoC3 on pyroptosis were mitigated by the use of a pyroptosis inhibitor or an ROS inhibitor in the ALI model. Furthermore, ApoC3 activated the expression of SYK, which in turn induced NLRP3 inflammasome-regulated pyroptosis in the ALI model. METTL3 was found to mediate the m6A mRNA expression of ApoC3. Overall, our study highlights the crucial role of ApoC3 in promoting macrophage pyroptosis in ALI through calcium-dependent ROS production and NLRP3 inflammasome activation via the SCIMP-SYK pathway, providing a potential therapeutic strategy for ALI and other inflammatory diseases.
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Affiliation(s)
- Zhichen Pu
- Drug Clinical Evaluation, Yijishan Hospital of Wannan Medical College, Wuhu, Anhui 241001, China; Key Laboratory of Non-coding RNA Transformation Research of Anhui Higher Education Institution, Wannan Medical College, Wuhu 241001, China; State Key Laboratory of Natural Medicines, Key Lab of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Tongjiaxiang 24, Nanjing 210009, China
| | - Wenhui Wang
- Drug Clinical Evaluation, Yijishan Hospital of Wannan Medical College, Wuhu, Anhui 241001, China
| | - Haitang Xie
- Drug Clinical Evaluation, Yijishan Hospital of Wannan Medical College, Wuhu, Anhui 241001, China.
| | - Wusan Wang
- Department of Pharmacology, Wannan Medical College, Wuhu, Anhui 241001, China.
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Pei X, Liu L, Wang J, Guo C, Li Q, Li J, Ren Q, Ma R, Zheng Y, Zhang Y, Liu L, Zheng D, Wang P, Jiang P, Feng X, Jiang E, Wang Y, Feng S. Exosomal secreted SCIMP regulates communication between macrophages and neutrophils in pneumonia. Nat Commun 2024; 15:691. [PMID: 38263143 PMCID: PMC10805922 DOI: 10.1038/s41467-024-44714-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 01/02/2024] [Indexed: 01/25/2024] Open
Abstract
In pneumonia, the deficient or delayed pathogen clearance can lead to pathogen proliferation and subsequent overactive immune responses, inducing acute lung injury (ALI). While screening human genome coding genes using our peripheral blood cell chemotactic platform, we unexpectedly find SLP adaptor and CSK interacting membrane protein (SCIMP), a protein with neutrophil chemotactic activity secreted during ALI. However, the specific role of SCIMP in ALI remains unclear. In this study, we investigate the secretion of SCIMP in exosomes (SCIMPexo) by macrophages after bacterial stimulation, both in vitro and in vivo. We observe a significant increase in the levels of SCIMPexo in bronchoalveolar lavage fluid and serum of pneumonia patients. We also find that bronchial perfusion with SCIMPexo or SCIMP N-terminal peptides increases the survival rate of the ALI model. This occurs due to the chemoattraction and activation of peripheral neutrophils dependent on formyl peptide receptor 1/2 (FPR1/2). Conversely, exosome suppressors and FPR1/2 antagonists decrease the survival rate in the lethal ALI model. Scimp-deficient and Fpr1/2-deficient mice also have lower survival rates and shorter survival times than wild-type mice. However, bronchial perfusion of SCIMP rescues Scimp-deficient mice but not Fpr1/2-deficient mice. Collectively, our findings suggest that the macrophage-SCIMP-FPRs-neutrophil axis plays a vital role in the innate immune process underlying ALI.
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Affiliation(s)
- Xiaolei Pei
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Hematopoietic Stem Cell Transplantation Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, 300020, P. R. China.
- Tianjin Institutes of Health Science, Tianjin, 301600, P. R. China.
| | - Li Liu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Hematopoietic Stem Cell Transplantation Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, 300020, P. R. China
- Tianjin Institutes of Health Science, Tianjin, 301600, P. R. China
| | - Jieru Wang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Hematopoietic Stem Cell Transplantation Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, 300020, P. R. China
- Tianjin Institutes of Health Science, Tianjin, 301600, P. R. China
| | - Changyuan Guo
- Department of Immunology, School of Basic Medical Sciences and NHC Key Laboratory of Medical Immunology, Peking University, Beijing, 100191, P. R. China
| | - Qingqing Li
- Department of Immunology, School of Basic Medical Sciences and NHC Key Laboratory of Medical Immunology, Peking University, Beijing, 100191, P. R. China
| | - Jia Li
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Hematopoietic Stem Cell Transplantation Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, 300020, P. R. China
- Tianjin Institutes of Health Science, Tianjin, 301600, P. R. China
| | - Qian Ren
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Hematopoietic Stem Cell Transplantation Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, 300020, P. R. China
- Tianjin Institutes of Health Science, Tianjin, 301600, P. R. China
| | - Runzhi Ma
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Hematopoietic Stem Cell Transplantation Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, 300020, P. R. China
- Tianjin Institutes of Health Science, Tianjin, 301600, P. R. China
| | - Yi Zheng
- Department of Immunology, School of Basic Medical Sciences and NHC Key Laboratory of Medical Immunology, Peking University, Beijing, 100191, P. R. China
| | - Yan Zhang
- Department of Immunology, School of Basic Medical Sciences and NHC Key Laboratory of Medical Immunology, Peking University, Beijing, 100191, P. R. China
| | - Li Liu
- Tianjin First Central Hospital, Tianjin Medical University, Tianjin, 300192, P. R. China
| | - Danfeng Zheng
- Department of Immunology, School of Basic Medical Sciences and NHC Key Laboratory of Medical Immunology, Peking University, Beijing, 100191, P. R. China
| | - Pingzhang Wang
- Department of Immunology, School of Basic Medical Sciences and NHC Key Laboratory of Medical Immunology, Peking University, Beijing, 100191, P. R. China
| | - Ping Jiang
- Tianjin First Central Hospital, Tianjin Medical University, Tianjin, 300192, P. R. China
| | - Xiaoming Feng
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Hematopoietic Stem Cell Transplantation Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, 300020, P. R. China
- Tianjin Institutes of Health Science, Tianjin, 301600, P. R. China
| | - Erlie Jiang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Hematopoietic Stem Cell Transplantation Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, 300020, P. R. China
- Tianjin Institutes of Health Science, Tianjin, 301600, P. R. China
| | - Ying Wang
- Department of Immunology, School of Basic Medical Sciences and NHC Key Laboratory of Medical Immunology, Peking University, Beijing, 100191, P. R. China.
| | - Sizhou Feng
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Hematopoietic Stem Cell Transplantation Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, 300020, P. R. China.
- Tianjin Institutes of Health Science, Tianjin, 301600, P. R. China.
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Muttathukunnel P, Wälti M, Aboouf MA, Köster-Hegmann C, Haenggi T, Gassmann M, Pannzanelli P, Fritschy JM, Schneider Gasser EM. Erythropoietin regulates developmental myelination in the brain stimulating postnatal oligodendrocyte maturation. Sci Rep 2023; 13:19522. [PMID: 37945644 PMCID: PMC10636124 DOI: 10.1038/s41598-023-46783-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 11/05/2023] [Indexed: 11/12/2023] Open
Abstract
Myelination is a process tightly regulated by a variety of neurotrophic factors. Here, we show-by analyzing two transgenic mouse lines, one overexpressing EPO selectively in the brain Tg21(PDGFB-rhEPO) and another with targeted removal of EPO receptors (EPORs) from oligodendrocyte progenitor cells (OPC)s (Sox10-cre;EpoRfx/fx mice)-a key function for EPO in regulating developmental brain myelination. Overexpression of EPO resulted in faster postnatal brain growth and myelination, an increased number of myelinating oligodendrocytes, faster axonal myelin ensheathment, and improved motor coordination. Conversely, targeted ablation of EPORs from OPCs reduced the number of mature oligodendrocytes and impaired motor coordination during the second postnatal week. Furthermore, we found that EPORs are transiently expressed in the subventricular zone (SVZ) during the second postnatal week and EPO increases the postnatal expression of essential oligodendrocyte pro-differentiation and pro-maturation (Nkx6.2 and Myrf) transcripts, and the Nfatc2/calcineurin pathway. In contrast, ablation of EPORs from OPCs inactivated the Erk1/2 pathway and reduced the postnatal expression of the transcripts. Our results reveal developmental time windows in which EPO therapies could be highly effective for stimulating oligodendrocyte maturation and myelination.
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Affiliation(s)
- Paola Muttathukunnel
- Institute of Pharmacology and Toxicology, University of Zürich, 8057, Zürich, Switzerland
- Center for Neuroscience Zurich (ZNZ), Zurich, Switzerland
| | - Michael Wälti
- Institute of Pharmacology and Toxicology, University of Zürich, 8057, Zürich, Switzerland
| | - Mostafa A Aboouf
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zürich, 8057, Zurich, Switzerland
- Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, 8057, Zurich, Switzerland
- Department of Biochemistry, Faculty of Pharmacy, Ain Shams University, Cairo, 11566, Egypt
| | - Christina Köster-Hegmann
- Institute of Pharmacology and Toxicology, University of Zürich, 8057, Zürich, Switzerland
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zürich, 8057, Zurich, Switzerland
| | - Tatjana Haenggi
- Institute of Pharmacology and Toxicology, University of Zürich, 8057, Zürich, Switzerland
| | - Max Gassmann
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zürich, 8057, Zurich, Switzerland
- Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, 8057, Zurich, Switzerland
| | - Patrizia Pannzanelli
- Rita Levi Montalcini Center for Brain Repair, University of Turin, 10126, Turin, Italy
| | - Jean-Marc Fritschy
- Institute of Pharmacology and Toxicology, University of Zürich, 8057, Zürich, Switzerland
- Center for Neuroscience Zurich (ZNZ), Zurich, Switzerland
| | - Edith M Schneider Gasser
- Institute of Pharmacology and Toxicology, University of Zürich, 8057, Zürich, Switzerland.
- Center for Neuroscience Zurich (ZNZ), Zurich, Switzerland.
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zürich, 8057, Zurich, Switzerland.
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Curson JE, Liu L, Luo L, Muusse TW, Lucas RM, Gunther KS, Vajjhala PR, Abrol R, Jones A, Kapetanovic R, Stacey KJ, Stow JL, Sweet MJ. TLR4 phosphorylation at tyrosine 672 activates the ERK/c-FOS signaling module for LPS-induced cytokine responses in macrophages. Eur J Immunol 2023; 53:e2250056. [PMID: 37058370 PMCID: PMC10947571 DOI: 10.1002/eji.202250056] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 03/20/2023] [Accepted: 04/11/2023] [Indexed: 04/15/2023]
Abstract
TLRs engage numerous adaptor proteins and signaling molecules, enabling a complex series of post-translational modifications (PTMs) to mount inflammatory responses. TLRs themselves are post-translationally modified following ligand-induced activation, with this being required to relay the full spectrum of proinflammatory signaling responses. Here, we reveal indispensable roles for TLR4 Y672 and Y749 phosphorylation in mounting optimal LPS-inducible inflammatory responses in primary mouse macrophages. LPS promotes phosphorylation at both tyrosine residues, with Y749 phosphorylation being required for maintenance of total TLR4 protein levels and Y672 phosphorylation exerting its pro-inflammatory effects more selectively by initiating ERK1/2 and c-FOS phosphorylation. Our data also support a role for the TLR4-interacting membrane proteins SCIMP and the SYK kinase axis in mediating TLR4 Y672 phosphorylation to permit downstream inflammatory responses in murine macrophages. The corresponding residue in human TLR4 (Y674) is also required for optimal LPS signaling responses. Our study, thus, reveals how a single PTM on one of the most widely studied innate immune receptors orchestrates downstream inflammatory responses.
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Affiliation(s)
- James E.B. Curson
- Institute for Molecular Bioscience (IMB)IMB Centre for Inflammation and Disease Research and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
| | - Liping Liu
- Institute for Molecular Bioscience (IMB)IMB Centre for Inflammation and Disease Research and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
| | - Lin Luo
- Institute for Molecular Bioscience (IMB)IMB Centre for Inflammation and Disease Research and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
| | - Timothy W. Muusse
- School of Chemistry and Molecular Biosciences (SCMB) and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
| | - Richard M. Lucas
- Institute for Molecular Bioscience (IMB)IMB Centre for Inflammation and Disease Research and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
| | - Kimberley S. Gunther
- Institute for Molecular Bioscience (IMB)IMB Centre for Inflammation and Disease Research and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
| | - Parimala R. Vajjhala
- School of Chemistry and Molecular Biosciences (SCMB) and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
| | - Rishika Abrol
- Institute for Molecular Bioscience (IMB)IMB Centre for Inflammation and Disease Research and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
| | - Alun Jones
- Institute for Molecular Bioscience (IMB)IMB Centre for Inflammation and Disease Research and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
| | - Ronan Kapetanovic
- Institute for Molecular Bioscience (IMB)IMB Centre for Inflammation and Disease Research and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
- Friedrich Miescher Institute for Biomedical ResearchBaselSwitzerland
| | - Katryn J. Stacey
- School of Chemistry and Molecular Biosciences (SCMB) and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
| | - Jennifer L. Stow
- Institute for Molecular Bioscience (IMB)IMB Centre for Inflammation and Disease Research and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
| | - Matthew J. Sweet
- Institute for Molecular Bioscience (IMB)IMB Centre for Inflammation and Disease Research and Australian Infectious Diseases Research CentreThe University of QueenslandBrisbaneQueenslandAustralia
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Morton CO, Griffiths JS, Loeffler J, Orr S, White PL. Defective antifungal immunity in patients with COVID-19. Front Immunol 2022; 13:1080822. [PMID: 36531987 PMCID: PMC9750792 DOI: 10.3389/fimmu.2022.1080822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 11/11/2022] [Indexed: 12/05/2022] Open
Abstract
The COVID-19 pandemic has placed a huge strain on global healthcare and been a significant cause of increased morbidity and mortality, particularly in at-risk populations. This disease attacks the respiratory systems and causes significant immune dysregulation in affected patients creating a perfect opportunity for the development of invasive fungal disease (IFD). COVID-19 infection can instill a significant, poorly regulated pro-inflammatory response. Clinically induced immunosuppression or pro-inflammatory damage to mucosa facilitate the development of IFD and Aspergillus, Mucorales, and Candida infections have been regularly reported throughout the COVID-19 pandemic. Corticosteroids and immune modulators are used in the treatment of COVID-19. Corticosteroid use is also a risk factor for IFD, but not the only reason for IFD in COVID -19 patients. Specific dysregulation of the immune system through functional exhaustion of Natural killer (NK) cells and T cells has been observed in COVID-19 through the expression of the exhaustion markers NK-G2A and PD-1. Reduced fungicidal activity of neutrophils from COVID-19 patients indicates that immune dysfunction/imbalance are important risk factors for IFD. The COVID-19 pandemic has significantly increased the at-risk population for IFD. Even if the incidence of IFD is relatively low, the size of this new at-risk population will result in a substantial increase in the overall, annual number of IFD cases. It is important to understand how and why certain patients with COVID-19 developed increased susceptibility to IFD, as this will improve our understanding of risk of IFD in the face of future pandemics but also in a clinical era of increased clinical immuno-suppression/modulation.
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Affiliation(s)
| | - James S. Griffiths
- Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral and Craniofacial Sciences, London, United Kingdom
| | - Juergen Loeffler
- Department of Internal Medicine II, University Hospital of Würzburg, Würzburg, Germany
| | - Selinda Orr
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Science, Queen’s University Belfast, Belfast, United Kingdom
| | - P. Lewis White
- Public Health Wales, Microbiology Cardiff, Wales, United Kingdom,*Correspondence: P. Lewis White,
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Lucas RM, Luo L, Stow JL. ERK1/2 in immune signalling. Biochem Soc Trans 2022; 50:1341-1352. [PMID: 36281999 PMCID: PMC9704528 DOI: 10.1042/bst20220271] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 10/07/2022] [Accepted: 10/10/2022] [Indexed: 07/30/2023]
Abstract
Extracellular signal-related kinases 1 and 2 (ERK1/2) are the final components of the mitogen-activated protein kinase (MAPK) phosphorylation cascade, an integral module in a diverse array of signalling pathways for shaping cell behaviour and fate. More recently, studies have shown that ERK1/2 plays an essential role downstream of immune receptors to elicit inflammatory gene expression in response to infection and cell or tissue damage. Much of this work has studied ERK1/2 activation in Toll-like receptor (TLR) pathways, providing mechanistic insights into its recruitment, compartmentalisation and activation in cells of the innate immune system. In this review, we summarise the typical activation of ERK1/2 in growth factor receptor pathways before discussing its known roles in immune cell signalling with a focus downstream of TLRs. We examine emerging research uncovering evidence of dysfunctional ERK1/2 signalling in inflammatory diseases and discuss the potential therapeutic benefit of targeting ERK1/2 pathways in inflammation.
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Affiliation(s)
- Richard M. Lucas
- Institute for Molecular Bioscience (IMB) and Centre for Inflammation and Disease Research, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Lin Luo
- Institute for Molecular Bioscience (IMB) and Centre for Inflammation and Disease Research, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Jennifer L. Stow
- Institute for Molecular Bioscience (IMB) and Centre for Inflammation and Disease Research, The University of Queensland, St Lucia, QLD 4072, Australia
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10
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The transmembrane adapter SCIMP recruits tyrosine kinase Syk to phosphorylate Toll-like receptors to mediate selective inflammatory outputs. J Biol Chem 2022; 298:101857. [PMID: 35337798 PMCID: PMC9052152 DOI: 10.1016/j.jbc.2022.101857] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 03/08/2022] [Accepted: 03/11/2022] [Indexed: 11/23/2022] Open
Abstract
Innate immune signaling by Toll-like receptors (TLRs) involves receptor phosphorylation, which helps to shape and drive key inflammatory outputs, yet our understanding of the kinases and mechanisms that mediate TLR phosphorylation is incomplete. Spleen tyrosine kinase (Syk) is a nonreceptor protein tyrosine kinase, which is known to relay adaptive and innate immune signaling, including from TLRs. However, TLRs do not contain the conserved dual immunoreceptor tyrosine-based activation motifs that typically recruit Syk to many other receptors. One possibility is that the Syk-TLR association is indirect, relying on an intermediary scaffolding protein. We previously identified a role for the palmitoylated transmembrane adapter protein SCIMP in scaffolding the Src tyrosine kinase Lyn, for TLR phosphorylation, but the role of SCIMP in mediating the interaction between Syk and TLRs has not yet been investigated. Here, we show that SCIMP recruits Syk in response to lipopolysaccharide-mediated TLR4 activation. We also show that Syk contributes to the phosphorylation of SCIMP and TLR4 to enhance their binding. Further evidence pinpoints two specific phosphorylation sites in SCIMP critical for its interaction with Syk-SH2 domains in the absence of immunoreceptor tyrosine-based activation motifs. Finally, using inhibitors and primary macrophages from SCIMP-/- mice, we confirm a functional role for SCIMP-mediated Syk interaction in modulating TLR4 phosphorylation, signaling, and cytokine outputs. In conclusion, we identify SCIMP as a novel, immune-specific Syk scaffold, which can contribute to inflammation through selective TLR-driven inflammatory responses.
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11
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Lebowitz JJ, Trinkle M, Bunzow JR, Balcita-Pedicino JJ, Hetelekides S, Robinson B, De La Torre S, Aicher SA, Sesack SR, Williams JT. Subcellular localization of D2 receptors in the murine substantia nigra. Brain Struct Funct 2021; 227:925-941. [PMID: 34854963 DOI: 10.1007/s00429-021-02432-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 11/08/2021] [Indexed: 12/13/2022]
Abstract
G-protein-coupled D2 autoreceptors expressed on dopamine neurons (D2Rs) inhibit transmitter release and cell firing at axonal endings and somatodendritic compartments. Mechanistic details of somatodendritic dopamine release remain unresolved, partly due to insufficient information on the subcellular distribution of D2Rs. Previous studies localizing D2Rs have been hindered by a dearth of antibodies validated for specificity in D2R knockout animals and have been limited by the small sampling areas imaged by electron microscopy. This study utilized sub-diffraction fluorescence microscopy and electron microscopy to examine D2 receptors in a superecliptic pHlourin GFP (SEP) epitope-tagged D2 receptor knockin mouse. Incubating live slices with an anti-SEP antibody achieved the selective labeling of plasma membrane-associated receptors for immunofluorescent imaging over a large area of the substantia nigra pars compacta (SNc). SEP-D2Rs appeared as puncta-like structures along the surface of dendrites and soma of dopamine neurons visualized by antibodies to tyrosine hydroxylase (TH). TH-associated SEP-D2Rs displayed a cell surface density of 0.66 puncta/µm2, which corresponds to an average frequency of 1 punctum every 1.50 µm. Separate ultrastructural experiments using silver-enhanced immunogold revealed that membrane-bound particles represented 28% of total D2Rs in putative dopamine cells within the SNc. Structures immediately adjacent to dendritic membrane gold particles were unmyelinated axons or axon varicosities (40%), astrocytes (19%), other dendrites (7%), or profiles unidentified (34%) in single sections. Some apposed profiles also expressed D2Rs. Fluorescent and ultrastructural analyses also provided the first visualization of membrane D2Rs at the axon initial segment, a compartment critical for action potential generation. The punctate appearance of anti-SEP staining indicates there is a population of D2Rs organized in discrete signaling sites along the plasma membrane, and for the first time, a quantitative estimate of spatial frequency is provided.
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Affiliation(s)
- Joseph J Lebowitz
- Vollum Institute, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Mason Trinkle
- Departments of Neuroscience, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - James R Bunzow
- Vollum Institute, Oregon Health and Science University, Portland, OR, 97239, USA
| | | | - Savas Hetelekides
- Departments of Neuroscience, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Brooks Robinson
- Vollum Institute, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Santiago De La Torre
- Vollum Institute, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Sue A Aicher
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Susan R Sesack
- Departments of Neuroscience, University of Pittsburgh, Pittsburgh, PA, 15260, USA.,Departments of Psychiatry, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - John T Williams
- Vollum Institute, Oregon Health and Science University, Portland, OR, 97239, USA.
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