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Riitano G, Capozzi A, Recalchi S, Augusto M, Conti F, Misasi R, Garofalo T, Sorice M, Manganelli V. Role of Lipid Rafts on LRP8 Signaling Triggered by Anti-β2-GPI Antibodies in Endothelial Cells. Biomedicines 2023; 11:3135. [PMID: 38137358 PMCID: PMC10740635 DOI: 10.3390/biomedicines11123135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 11/16/2023] [Accepted: 11/23/2023] [Indexed: 12/24/2023] Open
Abstract
Antiphospholipid antibody syndrome is an autoimmune disease characterized by thrombosis and/or pregnancy morbidity in association with circulating antiphospholipid antibodies, mainly anti-β2 glycoprotein 1 antibodies (anti-β2-GPI antibodies). Previous studies demonstrated that the signaling pathway may involve lipid rafts, plasma membrane microdomains enriched in glycosphingolipid and cholesterol. In this study, we analyzed the signaling pathway of LRP8/ApoER2, a putative receptor of anti-β2-GPI antibodies, through lipid rafts in human endothelial cells. LRP8, Dab2 and endothelial nitric oxide synthase (e-NOS) phosphorylation were evaluated using Western blot, Nitric Oxide (NO) production with cytofluorimetric analysis, LRP8 enrichment in lipid rafts via sucrose gradient fractionation, and scanning confocal microscopy analysis of its association with ganglioside GM1 was also conducted. The analyses demonstrated that affinity-purified anti-β2-GPI antibodies induced LRP8 and Dab-2 phosphorylation, together with a significant decrease in e-NOS phosphorylation, with consequent decrease in NO intracellular production. These effects were almost completely prevented by Methyl-β-cyclodextrin (MβCD), indicating the involvement of lipid rafts. It was supported with the observation of LRP8 enrichment in lipid raft fractions and its association with ganglioside GM1, detected with scanning confocal microscopy. These findings demonstrate that LRP8 signaling triggered by anti-β2-GPI antibodies in endothelial cells occurs through lipid rafts. It represents a new task for valuable therapeutic approaches, such as raft-targeted therapy, including cyclodextrins and statins.
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Affiliation(s)
- Gloria Riitano
- Department of Experimental Medicine, “Sapienza” University of Rome, 00161 Rome, Italy; (G.R.); (A.C.); (S.R.); (R.M.); (T.G.); (V.M.)
| | - Antonella Capozzi
- Department of Experimental Medicine, “Sapienza” University of Rome, 00161 Rome, Italy; (G.R.); (A.C.); (S.R.); (R.M.); (T.G.); (V.M.)
| | - Serena Recalchi
- Department of Experimental Medicine, “Sapienza” University of Rome, 00161 Rome, Italy; (G.R.); (A.C.); (S.R.); (R.M.); (T.G.); (V.M.)
| | | | - Fabrizio Conti
- Rheumatology Unit, Department of Clinical Internal, Anesthesiological and Cardiovascular Sciences, “Sapienza” University of Rome, 00161 Rome, Italy;
| | - Roberta Misasi
- Department of Experimental Medicine, “Sapienza” University of Rome, 00161 Rome, Italy; (G.R.); (A.C.); (S.R.); (R.M.); (T.G.); (V.M.)
| | - Tina Garofalo
- Department of Experimental Medicine, “Sapienza” University of Rome, 00161 Rome, Italy; (G.R.); (A.C.); (S.R.); (R.M.); (T.G.); (V.M.)
| | - Maurizio Sorice
- Department of Experimental Medicine, “Sapienza” University of Rome, 00161 Rome, Italy; (G.R.); (A.C.); (S.R.); (R.M.); (T.G.); (V.M.)
| | - Valeria Manganelli
- Department of Experimental Medicine, “Sapienza” University of Rome, 00161 Rome, Italy; (G.R.); (A.C.); (S.R.); (R.M.); (T.G.); (V.M.)
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Santilli F, Fabrizi J, Martellucci S, Santacroce C, Iorio E, Pisanu ME, Chirico M, Lancia L, Pulcini F, Manganelli V, Sorice M, Delle Monache S, Mattei V. Lipid rafts mediate multilineage differentiation of human dental pulp-derived stem cells (DPSCs). Front Cell Dev Biol 2023; 11:1274462. [PMID: 38020931 PMCID: PMC10665896 DOI: 10.3389/fcell.2023.1274462] [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: 08/08/2023] [Accepted: 10/23/2023] [Indexed: 12/01/2023] Open
Abstract
Cell outer membranes contain glycosphingolipids and protein receptors, which are integrated into glycoprotein domains, known as lipid rafts, which are involved in a variety of cellular processes, including receptor-mediated signal transduction and cellular differentiation process. In this study, we analyzed the lipidic composition of human Dental Pulp-Derived Stem Cells (DPSCs), and the role of lipid rafts during the multilineage differentiation process. The relative quantification of lipid metabolites in the organic fraction of DPSCs, performed by Nuclear Magnetic Resonance (NMR) spectroscopy, showed that mono-unsaturated fatty acids (MUFAs) were the most representative species in the total pool of acyl chains, compared to polyunsatured fatty acids (PUFAs). In addition, the stimulation of DPSCs with different culture media induces a multilineage differentiation process, determining changes in the gangliosides pattern. To understand the functional role of lipid rafts during multilineage differentiation, DPSCs were pretreated with a typical lipid raft affecting agent (MβCD). Subsequently, DPSCs were inducted to differentiate into osteoblast, chondroblast and adipoblast cells with specific media. We observed that raft-affecting agent MβCD prevented AKT activation and the expression of lineage-specific mRNA such as OSX, PPARγ2, and SOX9 during multilineage differentiation. Moreover, this compound significantly prevented the tri-lineage differentiation induced by specific stimuli, indicating that lipid raft integrity is essential for DPSCs differentiation. These results suggest that lipid rafts alteration may affect the signaling pathway activated, preventing multilineage differentiation.
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Affiliation(s)
- Francesca Santilli
- Biomedicine and Advanced Technologies Rieti Center, “Sabina Universitas”, Rieti, Italy
| | - Jessica Fabrizi
- Biomedicine and Advanced Technologies Rieti Center, “Sabina Universitas”, Rieti, Italy
- Department of Experimental Medicine, “Sapienza” University of Rome, Rome, Italy
| | - Stefano Martellucci
- Biomedicine and Advanced Technologies Rieti Center, “Sabina Universitas”, Rieti, Italy
| | - Costantino Santacroce
- Biomedicine and Advanced Technologies Rieti Center, “Sabina Universitas”, Rieti, Italy
| | - Egidio Iorio
- High Resolution NMR Unit, Core Facilities, Istituto Superiore di Sanità, Rome, Italy
| | - Maria Elena Pisanu
- High Resolution NMR Unit, Core Facilities, Istituto Superiore di Sanità, Rome, Italy
| | - Mattea Chirico
- High Resolution NMR Unit, Core Facilities, Istituto Superiore di Sanità, Rome, Italy
| | - Loreto Lancia
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, L’Aquila, Italy
| | - Fanny Pulcini
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, L’Aquila, Italy
| | - Valeria Manganelli
- Department of Experimental Medicine, “Sapienza” University of Rome, Rome, Italy
| | - Maurizio Sorice
- Department of Experimental Medicine, “Sapienza” University of Rome, Rome, Italy
| | - Simona Delle Monache
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, L’Aquila, Italy
| | - Vincenzo Mattei
- Dipartimento di Scienze della Vita, della Salute e delle Professioni Sanitarie, Link Campus University, Rome, Italy
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Riitano G, Recalchi S, Capozzi A, Manganelli V, Misasi R, Garofalo T, Sorice M, Longo A. The Role of Autophagy as a Trigger of Post-Translational Modifications of Proteins and Extracellular Vesicles in the Pathogenesis of Rheumatoid Arthritis. Int J Mol Sci 2023; 24:12764. [PMID: 37628944 PMCID: PMC10454292 DOI: 10.3390/ijms241612764] [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: 07/12/2023] [Revised: 08/11/2023] [Accepted: 08/12/2023] [Indexed: 08/27/2023] Open
Abstract
Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease, characterized by persistent joint inflammation, leading to cartilage and bone destruction. Autoantibody production is directed to post-translational modified (PTM) proteins, i.e., citrullinated or carbamylated. Autophagy may be the common feature in several types of stress (smoking, joint injury, and infections) and may be involved in post-translational modifications (PTMs) in proteins and the generation of citrullinated and carbamylated peptides recognized by the immune system in RA patients, with a consequent breakage of tolerance. Interestingly, autophagy actively provides information to neighboring cells via a process called secretory autophagy. Secretory autophagy combines the autophagy machinery with the secretion of cellular content via extracellular vesicles (EVs). A role for exosomes in RA pathogenesis has been recently demonstrated. Exosomes are involved in intercellular communications, and upregulated proteins and RNAs may contribute to the development of inflammatory arthritis and the progression of RA. In RA, most of the exosomes are produced by leukocytes and synoviocytes, which are loaded with PTM proteins, mainly citrullinated proteins, inflammatory molecules, and enzymes that are implicated in RA pathogenesis. Microvesicles derived from cell plasma membrane may also be loaded with PTM proteins, playing a role in the immunopathogenesis of RA. An analysis of changes in EV profiles, including PTM proteins, could be a useful tool for the prevention of inflammation in RA patients and help in the discovery of personalized medicine.
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Affiliation(s)
| | | | | | | | | | | | - Maurizio Sorice
- Department of Experimental Medicine, “Sapienza” University of Rome, 00161 Rome, Italy; (G.R.); (S.R.); (A.C.); (V.M.); (R.M.); (T.G.); (A.L.)
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Capozzi A, Manganelli V, Riitano G, Caissutti D, Longo A, Garofalo T, Sorice M, Misasi R. Advances in the Pathophysiology of Thrombosis in Antiphospholipid Syndrome: Molecular Mechanisms and Signaling through Lipid Rafts. J Clin Med 2023; 12:jcm12030891. [PMID: 36769539 PMCID: PMC9917860 DOI: 10.3390/jcm12030891] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/17/2023] [Accepted: 01/19/2023] [Indexed: 01/25/2023] Open
Abstract
The pathological features of antiphospholipid syndrome (APS) are related to the activity of circulating antiphospholipid antibodies (aPLs) associated with vascular thrombosis and obstetric complications. Indeed, aPLs are not only disease markers, but also play a determining pathogenetic role in APS and exert their effects through the activation of cells and coagulation factors and inflammatory mediators for the materialization of the thromboinflammatory pathogenetic mechanism. Cellular activation in APS necessarily involves the interaction of aPLs with target receptors on the cell membrane, capable of triggering the signal transduction pathway(s). This interaction occurs at specific microdomains of the cell plasma membrane called lipid rafts. In this review, we focus on the key role of lipid rafts as signaling platforms in the pathogenesis of APS, and propose this pathogenetic step as a strategic target of new therapies in order to improve classical anti-thrombotic approaches with "new" immunomodulatory drugs.
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Overexpression of Neuroglobin Promotes Energy Metabolism and Autophagy Induction in Human Neuroblastoma SH-SY5Y Cells. Cells 2021; 10:cells10123394. [PMID: 34943907 PMCID: PMC8699457 DOI: 10.3390/cells10123394] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/26/2021] [Accepted: 11/30/2021] [Indexed: 01/18/2023] Open
Abstract
Neuroglobin (NGB) is an O2-binding globin mainly expressed in the central and peripheral nervous systems and cerebrospinal fluid. Previously, it was demonstrated that NGB overexpression protects cells from hypoxia-induced death. To investigate processes promoted by NGB overexpression, we used a cellular model of neuroblastoma stably overexpressing an NGB-FLAG construct. We used a proteomic approach to identify the specific profile following NGB overexpression. To evaluate the role of NGB overexpression in increasing energetic metabolism, we measured oxygen consumption rate (OCR) and the extracellular acidification rate through Seahorse XF technology. The effect on autophagy induction was evaluated by analyzing SQSTM1/p62 and LC3-II expression. Proteomic analysis revealed several differentially regulated proteins, involved in oxidative phosphorylation and integral mitochondrial proteins linked to energy metabolism. The analysis of mitochondrial metabolism demonstrated that NGB overexpression increases mitochondrial ATP production. Indeed, NGB overexpression enhances bioenergetic metabolism, increasing OCR and oxygen consumption. Analysis of autophagy induction revealed an increase of LC3-II together with a significant decrease of SQSTM1/p62, and NGB-LC3-II association during autophagosome formation. These results highlight the active participation of NGB in several cellular processes that can be upregulated in response to NGB overexpression, playing a role in the adaptive response to stress in neuroblastoma cells.
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Crestini A, Santilli F, Martellucci S, Carbone E, Sorice M, Piscopo P, Mattei V. Prions and Neurodegenerative Diseases: A Focus on Alzheimer's Disease. J Alzheimers Dis 2021; 85:503-518. [PMID: 34864675 DOI: 10.3233/jad-215171] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Specific protein misfolding and aggregation are mechanisms underlying various neurodegenerative diseases such as prion disease and Alzheimer's disease (AD). The misfolded proteins are involved in prions, amyloid-β (Aβ), tau, and α-synuclein disorders; they share common structural, biological, and biochemical characteristics, as well as similar mechanisms of aggregation and self-propagation. Pathological features of AD include the appearance of plaques consisting of deposition of protein Aβ and neurofibrillary tangles formed by the hyperphosphorylated tau protein. Although it is not clear how protein aggregation leads to AD, we are learning that the cellular prion protein (PrPC) plays an important role in the pathogenesis of AD. Herein, we first examined the pathogenesis of prion and AD with a focus on the contribution of PrPC to the development of AD. We analyzed the mechanisms that lead to the formation of a high affinity bond between Aβ oligomers (AβOs) and PrPC. Also, we studied the role of PrPC as an AβO receptor that initiates an AβO-induced signal cascade involving mGluR5, Fyn, Pyk2, and eEF2K linking Aβ and tau pathologies, resulting in the death of neurons in the central nervous system. Finally, we have described how the PrPC-AβOs interaction can be used as a new potential therapeutic target for the treatment of PrPC-dependent AD.
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Affiliation(s)
- Alessio Crestini
- Department of Neuroscience, Istituto Superiore di Sanità, Rome, Italy
| | - Francesca Santilli
- Biomedicine and Advanced Technologies Rieti Center, "Sabina Universitas", Rieti, Italy.,Department of Experimental Medicine, "Sapienza" University, Rome, Italy
| | - Stefano Martellucci
- Biomedicine and Advanced Technologies Rieti Center, "Sabina Universitas", Rieti, Italy
| | - Elena Carbone
- Department of Neuroscience, Istituto Superiore di Sanità, Rome, Italy
| | - Maurizio Sorice
- Department of Experimental Medicine, "Sapienza" University, Rome, Italy
| | - Paola Piscopo
- Department of Neuroscience, Istituto Superiore di Sanità, Rome, Italy
| | - Vincenzo Mattei
- Biomedicine and Advanced Technologies Rieti Center, "Sabina Universitas", Rieti, Italy.,Department of Experimental Medicine, "Sapienza" University, Rome, Italy
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Role of ERLINs in the Control of Cell Fate through Lipid Rafts. Cells 2021; 10:cells10092408. [PMID: 34572057 PMCID: PMC8470593 DOI: 10.3390/cells10092408] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/27/2021] [Accepted: 09/09/2021] [Indexed: 12/14/2022] Open
Abstract
ER lipid raft-associated protein 1 (ERLIN1) and 2 (ERLIN2) are 40 kDa transmembrane glycoproteins belonging to the family of prohibitins, containing a PHB domain. They are generally localized in the endoplasmic reticulum (ER), where ERLIN1 forms a heteroligomeric complex with its closely related ERLIN2. Well-defined functions of ERLINS are promotion of ER-associated protein degradation, mediation of inositol 1,4,5-trisphosphate (IP3) receptors, processing and regulation of lipid metabolism. Until now, ERLINs have been exclusively considered protein markers of ER lipid raft-like microdomains. However, under pathophysiological conditions, they have been described within mitochondria-associated endoplasmic reticulum membranes (MAMs), tethering sites between ER and mitochondria, characterized by the presence of specialized raft-like subdomains enriched in cholesterol and gangliosides, which play a key role in the membrane scrambling and function. In this context, it is emerging that ER lipid raft-like microdomains proteins, i.e., ERLINs, may drive mitochondria-ER crosstalk under both physiological and pathological conditions by association with MAMs, regulating the two main processes underlined, survival and death. In this review, we describe the role of ERLINs in determining cell fate by controlling the “interchange” between apoptosis and autophagy pathways, considering that their alteration has a significant impact on the pathogenesis of several human diseases.
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Yokoyama N, Hanafusa K, Hotta T, Oshima E, Iwabuchi K, Nakayama H. Multiplicity of Glycosphingolipid-Enriched Microdomain-Driven Immune Signaling. Int J Mol Sci 2021; 22:9565. [PMID: 34502474 PMCID: PMC8430928 DOI: 10.3390/ijms22179565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/29/2021] [Accepted: 09/01/2021] [Indexed: 11/16/2022] Open
Abstract
Glycosphingolipids (GSLs), together with cholesterol, sphingomyelin (SM), and glycosylphosphatidylinositol (GPI)-anchored and membrane-associated signal transduction molecules, form GSL-enriched microdomains. These specialized microdomains interact in a cis manner with various immune receptors, affecting immune receptor-mediated signaling. This, in turn, results in the regulation of a broad range of immunological functions, including phagocytosis, cytokine production, antigen presentation and apoptosis. In addition, GSLs alone can regulate immunological functions by acting as ligands for immune receptors, and exogenous GSLs can alter the organization of microdomains and microdomain-associated signaling. Many pathogens, including viruses, bacteria and fungi, enter host cells by binding to GSL-enriched microdomains. Intracellular pathogens survive inside phagocytes by manipulating intracellular microdomain-driven signaling and/or sphingolipid metabolism pathways. This review describes the mechanisms by which GSL-enriched microdomains regulate immune signaling.
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Affiliation(s)
- Noriko Yokoyama
- Institute for Environmental and Gender-Specific Medicine, Juntendo University, Graduate School of Medicine, Urayasu, Chiba 279-0021, Japan; (N.Y.); (K.H.); (T.H.); (E.O.); (K.I.)
| | - Kei Hanafusa
- Institute for Environmental and Gender-Specific Medicine, Juntendo University, Graduate School of Medicine, Urayasu, Chiba 279-0021, Japan; (N.Y.); (K.H.); (T.H.); (E.O.); (K.I.)
| | - Tomomi Hotta
- Institute for Environmental and Gender-Specific Medicine, Juntendo University, Graduate School of Medicine, Urayasu, Chiba 279-0021, Japan; (N.Y.); (K.H.); (T.H.); (E.O.); (K.I.)
| | - Eriko Oshima
- Institute for Environmental and Gender-Specific Medicine, Juntendo University, Graduate School of Medicine, Urayasu, Chiba 279-0021, Japan; (N.Y.); (K.H.); (T.H.); (E.O.); (K.I.)
| | - Kazuhisa Iwabuchi
- Institute for Environmental and Gender-Specific Medicine, Juntendo University, Graduate School of Medicine, Urayasu, Chiba 279-0021, Japan; (N.Y.); (K.H.); (T.H.); (E.O.); (K.I.)
- Laboratory of Biochemistry, Juntendo University Faculty of Health Care and Nursing, Urayasu, Chiba 279-0023, Japan
- Infection Control Nursing, Juntendo University Graduate School of Health Care and Nursing, Urayasu, Chiba 279-0023, Japan
| | - Hitoshi Nakayama
- Institute for Environmental and Gender-Specific Medicine, Juntendo University, Graduate School of Medicine, Urayasu, Chiba 279-0021, Japan; (N.Y.); (K.H.); (T.H.); (E.O.); (K.I.)
- Laboratory of Biochemistry, Juntendo University Faculty of Health Care and Nursing, Urayasu, Chiba 279-0023, Japan
- Infection Control Nursing, Juntendo University Graduate School of Health Care and Nursing, Urayasu, Chiba 279-0023, Japan
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Sorice M, Misasi R, Riitano G, Manganelli V, Martellucci S, Longo A, Garofalo T, Mattei V. Targeting Lipid Rafts as a Strategy Against Coronavirus. Front Cell Dev Biol 2021; 8:618296. [PMID: 33614627 PMCID: PMC7890255 DOI: 10.3389/fcell.2020.618296] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 12/21/2020] [Indexed: 12/15/2022] Open
Abstract
Lipid rafts are functional membrane microdomains containing sphingolipids, including gangliosides, and cholesterol. These regions are characterized by highly ordered and tightly packed lipid molecules. Several studies revealed that lipid rafts are involved in life cycle of different viruses, including coronaviruses. Among these recently emerged the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The main receptor for SARS-CoV-2 is represented by the angiotensin-converting enzyme-2 (ACE-2), although it also binds to sialic acids linked to host cell surface gangliosides. A new type of ganglioside-binding domain within the N-terminal portion of the SARS-CoV-2 spike protein was identified. Lipid rafts provide a suitable platform able to concentrate ACE-2 receptor on host cell membranes where they may interact with the spike protein on viral envelope. This review is focused on selective targeting lipid rafts components as a strategy against coronavirus. Indeed, cholesterol-binding agents, including statins or methyl-β-cyclodextrin (MβCD), can affect cholesterol, causing disruption of lipid rafts, consequently impairing coronavirus adhesion and binding. Moreover, these compounds can block downstream key molecules in virus infectivity, reducing the levels of proinflammatory molecules [tumor necrosis factor alpha (TNF-α), interleukin (IL)-6], and/or affecting the autophagic process involved in both viral replication and clearance. Furthermore, cyclodextrins can assemble into complexes with various drugs to form host-guest inclusions and may be used as pharmaceutical excipients of antiviral compounds, such as lopinavir and remdesivir, by improving bioavailability and solubility. In conclusion, the role of lipid rafts-affecting drugs in the process of coronavirus entry into the host cells prompts to introduce a new potential task in the pharmacological approach against coronavirus.
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Affiliation(s)
- Maurizio Sorice
- Department of Experimental Medicine, “Sapienza” University, Rome, Italy
| | - Roberta Misasi
- Department of Experimental Medicine, “Sapienza” University, Rome, Italy
| | - Gloria Riitano
- Department of Experimental Medicine, “Sapienza” University, Rome, Italy
| | | | - Stefano Martellucci
- Biomedicine and Advanced Technologies Rieti Center, “Sabina Universitas”, Rieti, Italy
| | - Agostina Longo
- Department of Experimental Medicine, “Sapienza” University, Rome, Italy
| | - Tina Garofalo
- Department of Experimental Medicine, “Sapienza” University, Rome, Italy
| | - Vincenzo Mattei
- Biomedicine and Advanced Technologies Rieti Center, “Sabina Universitas”, Rieti, Italy
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Prion Protein in Stem Cells: A Lipid Raft Component Involved in the Cellular Differentiation Process. Int J Mol Sci 2020; 21:ijms21114168. [PMID: 32545192 PMCID: PMC7312503 DOI: 10.3390/ijms21114168] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 06/08/2020] [Accepted: 06/09/2020] [Indexed: 12/13/2022] Open
Abstract
The prion protein (PrP) is an enigmatic molecule with a pleiotropic effect on different cell types; it is localized stably in lipid raft microdomains and it is able to recruit downstream signal transduction pathways by its interaction with various biochemical partners. Since its discovery, this lipid raft component has been involved in several functions, although most of the publications focused on the pathological role of the protein. Recent studies report a key role of cellular prion protein (PrPC) in physiological processes, including cellular differentiation. Indeed, the PrPC, whose expression is modulated according to the cell differentiation degree, appears to be part of the multimolecular signaling pathways of the neuronal differentiation process. In this review, we aim to summarize the main findings that report the link between PrPC and stem cells.
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Sasaki N, Toyoda M. Vascular Diseases and Gangliosides. Int J Mol Sci 2019; 20:ijms20246362. [PMID: 31861196 PMCID: PMC6941100 DOI: 10.3390/ijms20246362] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 12/12/2019] [Accepted: 12/16/2019] [Indexed: 02/07/2023] Open
Abstract
Vascular diseases, such as myocardial infarction and cerebral infarction, are most commonly caused by atherosclerosis, one of the leading causes of death worldwide. Risk factors for atherosclerosis include lifestyle and aging. It has been reported that lifespan could be extended in mice by targeting senescent cells, which led to the suppression of aging-related diseases, such as vascular diseases. However, the molecular mechanisms underlying the contribution of aging to vascular diseases are still not well understood. Several types of cells, such as vascular (endothelial cell), vascular-associated (smooth muscle cell and fibroblast) and inflammatory cells, are involved in plaque formation, plaque rupture and thrombus formation, which result in atherosclerosis. Gangliosides, a group of glycosphingolipids, are expressed on the surface of vascular, vascular-associated and inflammatory cells, where they play functional roles. Clarifying the role of gangliosides in atherosclerosis and their relationship with aging is fundamental to develop novel prevention and treatment methods for vascular diseases based on targeting gangliosides. In this review, we highlight the involvement and possible contribution of gangliosides to vascular diseases and further discuss their relationship with aging.
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Affiliation(s)
- Norihiko Sasaki
- Correspondence: (N.S.); (M.T.); Tel.: +81-3-3964-3241 (N.S.); +81-3-3964-4421 (M.T.)
| | - Masashi Toyoda
- Correspondence: (N.S.); (M.T.); Tel.: +81-3-3964-3241 (N.S.); +81-3-3964-4421 (M.T.)
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12
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Mattei V, Manganelli V, Martellucci S, Capozzi A, Mantuano E, Longo A, Ferri A, Garofalo T, Sorice M, Misasi R. A multimolecular signaling complex including PrP C and LRP1 is strictly dependent on lipid rafts and is essential for the function of tissue plasminogen activator. J Neurochem 2019; 152:468-481. [PMID: 31602645 DOI: 10.1111/jnc.14891] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 10/04/2019] [Accepted: 10/07/2019] [Indexed: 12/17/2022]
Abstract
Prion protein (PrPC ) localizes stably in lipid rafts microdomains and is able to recruit downstream signal transduction pathways by the interaction with promiscuous partners. Other proteins have the ability to occasionally be recruited to these specialized membrane areas, within multimolecular complexes. Among these, we highlight the presence of the low-density lipoprotein receptor-related protein 1 (LRP1), which was found localized transiently in lipid rafts, suggesting a different function of this receptor that through lipid raft becomes able to activate a signal transduction pathway triggered by specific ligands, including Tissue plasminogen activator (tPA). Since it has been reported that PrPC participates in the tPA-mediated plasminogen activation, in this study, we describe the role of lipid rafts in the recruitment and activation of downstream signal transduction pathways mediated by the interaction among tPA, PrPC and LRP1 in human neuroblastoma SK-N-BE2 cell line. Co-immunoprecipitation analysis reveals a consistent association between PrPC and GM1, as well as between LRP1 and GM1, indicating the existence of a glycosphingolipid-enriched multimolecular complex. In our cell model, knocking-down PrPC by siRNA impairs ERK phosphorylation induced by tPA. Moreover the alteration of the lipidic milieu of lipid rafts, perturbing the physical/functional interaction between PrPC and LRP1, inhibits this response. We show that LRP1 and PrPC , following tPA stimulation, may function as a system associated with lipid rafts, involved in receptor-mediated neuritogenic pathway. We suggest this as a multimolecular signaling complex, whose activity depends strictly on the integrity of lipid raft and is involved in the neuritogenic signaling.
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Affiliation(s)
- Vincenzo Mattei
- Biomedicine and Advanced Technologies Rieti Center, Sabina Universitas, Rieti, Italy.,Department of Experimental Medicine, Sapienza University, Rome, Italy
| | | | - Stefano Martellucci
- Biomedicine and Advanced Technologies Rieti Center, Sabina Universitas, Rieti, Italy.,Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Antonella Capozzi
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Elisabetta Mantuano
- Department of Experimental Medicine, Sapienza University, Rome, Italy.,Department of Pathology, University of California at San Diego, La Jolla, CA, USA
| | - Agostina Longo
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Alberto Ferri
- Institute of Cell Biology and Neurobiology, CNR, Rome, Italy.,Fondazione Santa Lucia IRCCS, c/o CERC, Rome, Italy
| | - Tina Garofalo
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Maurizio Sorice
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Roberta Misasi
- Department of Experimental Medicine, Sapienza University, Rome, Italy
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13
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Zhang T, de Waard AA, Wuhrer M, Spaapen RM. The Role of Glycosphingolipids in Immune Cell Functions. Front Immunol 2019; 10:90. [PMID: 30761148 PMCID: PMC6361815 DOI: 10.3389/fimmu.2019.00090] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Accepted: 01/14/2019] [Indexed: 01/06/2023] Open
Abstract
Glycosphingolipids (GSLs) exhibit a variety of functions in cellular differentiation and interaction. Also, they are known to play a role as receptors in pathogen invasion. A less well-explored feature is the role of GSLs in immune cell function which is the subject of this review article. Here we summarize knowledge on GSL expression patterns in different immune cells. We review the changes in GSL expression during immune cell development and differentiation, maturation, and activation. Furthermore, we review how immune cell GSLs impact membrane organization, molecular signaling, and trans-interactions in cellular cross-talk. Another aspect covered is the role of GSLs as targets of antibody-based immunity in cancer. We expect that recent advances in analytical and genome editing technologies will help in the coming years to further our knowledge on the role of GSLs as modulators of immune cell function.
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Affiliation(s)
- Tao Zhang
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, Netherlands
| | - Antonius A de Waard
- Department of Immunopathology, Sanquin Research, Amsterdam, Netherlands.,Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Manfred Wuhrer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, Netherlands
| | - Robbert M Spaapen
- Department of Immunopathology, Sanquin Research, Amsterdam, Netherlands.,Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
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14
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Garofalo T, Manganelli V, Grasso M, Mattei V, Ferri A, Misasi R, Sorice M. Role of mitochondrial raft-like microdomains in the regulation of cell apoptosis. Apoptosis 2015; 20:621-34. [PMID: 25652700 DOI: 10.1007/s10495-015-1100-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Lipid rafts are envisaged as lateral assemblies of specific lipids and proteins that dissociate and associate rapidly and form functional clusters in cell membranes. These structural platforms are not confined to the plasma membrane; indeed lipid microdomains are similarly formed at subcellular organelles, which include endoplasmic reticulum, Golgi and mitochondria, named raft-like microdomains. In addition, some components of raft-like microdomains are present within ER-mitochondria associated membranes. This review is focused on the role of mitochondrial raft-like microdomains in the regulation of cell apoptosis, since these microdomains may represent preferential sites where key reactions take place, regulating mitochondria hyperpolarization, fission-associated changes, megapore formation and release of apoptogenic factors. These structural platforms appear to modulate cytoplasmic pathways switching cell fate towards cell survival or death. Main insights on this issue derive from some pathological conditions in which alterations of microdomains structure or function can lead to severe alterations of cell activity and life span. In the light of the role played by raft-like microdomains to integrate apoptotic signals and in regulating mitochondrial dynamics, it is conceivable that these membrane structures may play a role in the mitochondrial alterations observed in some of the most common human neurodegenerative diseases, such as Amyotrophic lateral sclerosis, Huntington's chorea and prion-related diseases. These findings introduce an additional task for identifying new molecular target(s) of pharmacological agents in these pathologies.
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Affiliation(s)
- Tina Garofalo
- Department of Experimental Medicine, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy
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15
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McDonald G, Deepak S, Miguel L, Hall CJ, Isenberg DA, Magee AI, Butters T, Jury EC. Normalizing glycosphingolipids restores function in CD4+ T cells from lupus patients. J Clin Invest 2014; 124:712-24. [PMID: 24463447 DOI: 10.1172/jci69571] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 10/24/2013] [Indexed: 11/17/2022] Open
Abstract
Patients with the autoimmune rheumatic disease systemic lupus erythematosus (SLE) have multiple defects in lymphocyte signaling and function that contribute to disease pathogenesis. Such defects could be attributed to alterations in metabolic processes, including abnormal control of lipid biosynthesis pathways. Here, we reveal that CD4+ T cells from SLE patients displayed an altered profile of lipid raft-associated glycosphingolipids (GSLs) compared with that of healthy controls. In particular, lactosylceramide, globotriaosylceramide (Gb3), and monosialotetrahexosylganglioside (GM1) levels were markedly increased. Elevated GSLs in SLE patients were associated with increased expression of liver X receptor β (LXRβ), a nuclear receptor that controls cellular lipid metabolism and trafficking and influences acquired immune responses. Stimulation of CD4+ T cells isolated from healthy donors with synthetic and endogenous LXR agonists promoted GSL expression, which was blocked by an LXR antagonist. Increased GSL expression in CD4+ T cells was associated with intracellular accumulation and accelerated trafficking of GSL, reminiscent of cells from patients with glycolipid storage diseases. Inhibition of GSL biosynthesis in vitro with a clinically approved inhibitor (N-butyldeoxynojirimycin) normalized GSL metabolism, corrected CD4+ T cell signaling and functional defects, and decreased anti-dsDNA antibody production by autologous B cells in SLE patients. Our data demonstrate that lipid metabolism defects contribute to SLE pathogenesis and suggest that targeting GSL biosynthesis restores T cell function in SLE.
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16
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Nakayama H, Ogawa H, Takamori K, Iwabuchi K. GSL-Enriched Membrane Microdomains in Innate Immune Responses. Arch Immunol Ther Exp (Warsz) 2013; 61:217-28. [DOI: 10.1007/s00005-013-0221-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 02/13/2013] [Indexed: 12/20/2022]
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17
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Age-dependent changes in the sphingolipid composition of mouse CD4+ T cell membranes and immune synapses implicate glucosylceramides in age-related T cell dysfunction. PLoS One 2012; 7:e47650. [PMID: 23110086 PMCID: PMC3482221 DOI: 10.1371/journal.pone.0047650] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2012] [Accepted: 09/13/2012] [Indexed: 11/29/2022] Open
Abstract
To determine whether changes in sphingolipid composition are associated with age-related immune dysfunction, we analyzed the core sphingolipidome (i.e., all of the metabolites through the first headgroup additions) of young and aged CD4+ T cells. Since sphingolipids influence the biophysical properties of membranes, we evaluated the compositions of immune synapse (IS) and non-IS fractions prepared by magnetic immuno-isolation. Broadly, increased amounts of sphingomyelins, dihydrosphingomyelins and ceramides were found in aged CD4+ T cells. After normalizing for total sphingolipid content, a statistically significant decrease in the molar fraction of glucosylceramides was evident in both the non-IS and IS fractions of aged T cells. This change was balanced by less dramatic increases in the molar fractions of sphingomyelins and dihydrosphingomyelins in aged CD4+ T cells. In vitro, the direct or enzymatic enhancement of ceramide levels decreased CD4+ T cell proliferation without regard for the age of the responding T cells. In contrast, the in vitro inhibition of glucosylceramidase preferentially increased the proliferation of aged CD4+ T cells. These results suggest that reductions in glucosylceramide abundance contribute to age-related impairments in CD4+ T cell function.
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18
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CD4 and CD8 T cells require different membrane gangliosides for activation. Proc Natl Acad Sci U S A 2012; 109:E336-42. [PMID: 22308377 DOI: 10.1073/pnas.1114965109] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Initial events of T-cell activation involve movement of the T-cell receptor into lipid rafts. Gangliosides are major components of lipid rafts. While investigating T-cell activation in ganglioside-deficient mice, we observed that CD4(+) and CD8(+) T cells required different ganglioside subsets for activation. Activation of CD4(+) T cells from GM3 synthase-null mice, deficient in GM3-derived gangliosides, is severely compromised, whereas CD8(+) T-cell activation is normal. Conversely, in cells from GM2/GD2 synthase-null mice, expressing only GM3 and GD3, CD4(+) T-cell activation is normal, whereas CD8(+) T-cell activation is deficient. Supplementing the cells with the corresponding missing gangliosides restores normal activation. GM3 synthase-null mice do not develop experimental asthma. Distinct expression patterns of ganglioside species in CD4(+) T and CD8(+) T cells, perhaps in uniquely functional lipid rafts, define immune functions in each T-cell subset. Control of ganglioside expression would offer a strategy targeting for specific T-cell subpopulations to treat immune diseases.
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Wipfler D, Srinivasan GV, Sadick H, Kniep B, Arming S, Willhauck-Fleckenstein M, Vlasak R, Schauer R, Schwartz-Albiez R. Differentially regulated expression of 9-O-acetyl GD3 (CD60b) and 7-O-acetyl-GD3 (CD60c) during differentiation and maturation of human T and B lymphocytes. Glycobiology 2011; 21:1161-72. [PMID: 21507905 DOI: 10.1093/glycob/cwr050] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
GD3 (CD60a) and its 9-O-acetylated variant (CD60b) are intracellular regulators of apoptosis in T lymphocytes. Surface expressed 9-O-acetyl- and 7-O-acetyl-GD3 (CD60b and CD60c) may have a functional impact on activated T and B cells. In order to investigate the balance between surface and intracellular expression and synthesis and degradation of these glycosphingolipids in human lymphocytes of various differentiation stages, we analyzed (i) expression of GD3 molecules on native T and B cells and thymocytes by flow cytometry and (ii) activity and regulation of possible key enzymes for CD60a,b,c synthesis and degradation at the transcriptional level. Both, surface and cytoplasmic expression of CD60a and CD60c was highest in tonsillar T cells. In thymocytes, CD60c outweighs the other CD60 variants and was mainly found in the cytoplasm. All lymphocyte preparations contained sialate O-acetyltransferase activity producing 7-O-acetyl-GD3. Sialidase activity was highest in peripheral blood lymphocytes followed by thymocytes and tonsillar T and B cells. Transcription of GD3 synthase (ST8SiaI), the key enzyme for GD3 synthesis, was highest in tonsillar T cells, whereas transcriptional levels of sialidase NEU3 and O-acetylesterase H-Lse were lowest in activated T cells. This balance between enzymes of sialic acid metabolism may explain the strong overall staining intensity for all GD3 forms in T cells. Both CASD1, presumably encoding a sialic acid-specific O-acetyltransferase, and H-Lse showed highest transcription in peripheral B lymphocytes corresponding to the low expression of CD60b and c in these cells. Our data point to regulatory functions of these anabolic and catabolic key enzymes for the expression of GD3 and its O-acetylated variants in lymphocytes at a given differentiation stage.
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Affiliation(s)
- Dirk Wipfler
- German Cancer Research Center, D015 Translational Immunology, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
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20
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Prokazova NV, Samovilova NN, Gracheva EV, Golovanova NK. Ganglioside GM3 and its biological functions. BIOCHEMISTRY (MOSCOW) 2009; 74:235-49. [PMID: 19364317 DOI: 10.1134/s0006297909030018] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Metabolism, topology, and possible mechanisms for regulation of the ganglioside GM3 content in the cell are reviewed. Under consideration are biological functions of GM3, such as involvement in cell differentiation, proliferation, oncogenesis, and apoptosis.
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Affiliation(s)
- N V Prokazova
- Institute of Experimental Cardiology, Russian Cardiology Research Center, Russian Ministry of Health, 121552 Moscow, Russia.
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21
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Segregation of GM1 and GM3 clusters in the cell membrane depends on the intact actin cytoskeleton. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:388-96. [DOI: 10.1016/j.bbalip.2009.01.008] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Abstract
Tyrosine phosphorylation and dephosphorylation of proteins play a critical role for many T-cell functions. The opposing actions of protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs) determine the level of tyrosine phosphorylation at any time. It is well accepted that PTKs are essential during T-cell signaling; however, the role and importance of PTPs are much less known and appreciated. Both transmembrane and cytoplasmic tyrosine phosphatases have been identified in T cells and shown to regulate T-cell responses. This review focuses on the roles of the two cytoplasmic PTPs, the Src-homology 2 domain (SH2)-containing SHP-1 and SHP-2, in T-cell signaling, development, differentiation, and function.
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Affiliation(s)
- Ulrike Lorenz
- Department of Microbiology and The Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville, VA 22908-0734, USA.
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Chentouf M, Ghannam S, Bès C, Troadec S, Cérutti M, Chardès T. Recombinant anti-CD4 antibody 13B8.2 blocks membrane-proximal events by excluding the Zap70 molecule and downstream targets SLP-76, PLC gamma 1, and Vav-1 from the CD4-segregated Brij 98 detergent-resistant raft domains. THE JOURNAL OF IMMUNOLOGY 2007; 179:409-20. [PMID: 17579062 DOI: 10.4049/jimmunol.179.1.409] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The biological effects of rIgG(1) 13B8.2, directed against the CDR3-like loop on the D1 domain of CD4, are partly due to signals that prevent NF-kappaB nuclear translocation, but the precise mechanisms of action, particularly at the level of membrane proximal signaling, remain obscure. We support the hypothesis that rIgG(1) 13B8.2 acts by interfering with the spatiotemporal distribution of signaling or receptor molecules inside membrane rafts. Upon cross-linking of Jurkat T lymphocytes, rIgG(1) 13B8.2 was found to induce an accumulation/retention of the CD4 molecule inside polyoxyethylene-20 ether Brij 98 detergent-resistant membranes at 37 degrees C, together with recruitment of TCR, CD3zeta, p56 Lck, Lyn, and Syk p70 kinases, linker for activation of T cells, and Csk-binding protein/phosphoprotein associated with glycosphingolipid adaptor proteins, and protein kinase Ctheta, but excluded Zap70 and its downstream targets Src homology 2-domain-containing leukocyte protein of 76 kDa, phospholipase Cgamma1, and p95(vav). Analysis of key upstream events such as Zap70 phosphorylation showed that modulation of Tyr(292) and Tyr(319) phosphorylation occurred concomitantly with 13B8.2-induced Zap70 exclusion from the membrane rafts. 13B8.2-induced differential raft partitioning was epitope, cholesterol, and actin dependent but did not require Ab hyper-cross-linking. Fluorescence confocal imaging confirmed the spatiotemporal segregation of the CD4 complex inside rafts and concomitant Zap70 exclusion, which occurred within 10-30 s following rIgG(1) 13B8.2 ligation, reached a plateau at 1 min, and persisted until the end of the 1-h experiment. The differential spatiotemporal partitioning between the CD4 receptor and the Zap70-signaling kinase inside membrane rafts interrupts the proximal signal cross-talk leading to subsequent NF-kappaB nuclear translocation and explains how baculovirus-expressed CD4-CDR3-like-specific rIgG(1) 13B8.2 acts to induce its biological effects.
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Affiliation(s)
- Myriam Chentouf
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche 5236, Centre d'études d'agents Pathogènes et Biotechnologies pour la Santé, Faculté de Pharmacie, 15 Avenue Charles Flahault, 34093 Montpellier, France
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