1
|
Rahman I, Collado Sánchez A, Davies J, Rzeniewicz K, Abukscem S, Joachim J, Hoskins Green HL, Killock D, Sanz MJ, Charras G, Parsons M, Ivetic A. L-selectin regulates human neutrophil transendothelial migration. J Cell Sci 2021; 134:jcs.250340. [PMID: 33408247 PMCID: PMC7888707 DOI: 10.1242/jcs.250340] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 12/03/2020] [Indexed: 01/13/2023] Open
Abstract
The migration of circulating neutrophils towards damaged or infected tissue is absolutely critical to the inflammatory response. L-selectin is a cell adhesion molecule abundantly expressed on circulating neutrophils. For over two decades, neutrophil L-selectin has been assigned the exclusive role of supporting tethering and rolling – the initial stages of the multi-step adhesion cascade. Here, we provide direct evidence for L-selectin contributing to neutrophil transendothelial migration (TEM). We show that L-selectin co-clusters with PECAM-1 – a well-characterised cell adhesion molecule involved in regulating neutrophil TEM. This co-clustering behaviour occurs specifically during TEM, which serves to augment ectodomain shedding of L-selectin and expedite the time taken for TEM (TTT) to complete. Blocking PECAM-1 signalling (through mutation of its cytoplasmic tail), PECAM-1-dependent adhesion or L-selectin shedding, leads to a significant delay in the TTT. Finally, we show that co-clustering of L-selectin with PECAM-1 occurs specifically across TNF- but not IL-1β-activated endothelial monolayers – implying unique adhesion interactomes forming in a cytokine-specific manner. To our knowledge, this is the first report to implicate a non-canonical role for L-selectin in regulating neutrophil TEM. Highlighted Article: Neutrophil L-selectin co-clusters with PECAM-1 in cis during transendothelial migration (TEM). Clustering neutrophil PECAM-1 activates p38 MAPK and JNK to regulate L-selectin shedding, which in turn expedites TEM.
Collapse
Affiliation(s)
- Izajur Rahman
- BHF Centre for Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, James Black Centre, 125 Coldharbour Lane, London SE5 9NU, UK
| | - Aida Collado Sánchez
- Department of Pharmacology and Faculty of Medicine and Odontology, University of Valencia, Av. Blasco Ibáñez 15, 46010 Valencia, Spain.,Institute of Health Research INCLIVA, University Clinic Hospital of Valencia, Av. Menéndez Pelayo 4, 46010, Valencia, Spain
| | - Jessica Davies
- BHF Centre for Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, James Black Centre, 125 Coldharbour Lane, London SE5 9NU, UK
| | - Karolina Rzeniewicz
- BHF Centre for Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, James Black Centre, 125 Coldharbour Lane, London SE5 9NU, UK
| | - Sarah Abukscem
- BHF Centre for Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, James Black Centre, 125 Coldharbour Lane, London SE5 9NU, UK
| | - Justin Joachim
- BHF Centre for Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, James Black Centre, 125 Coldharbour Lane, London SE5 9NU, UK
| | - Hannah L Hoskins Green
- BHF Centre for Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, James Black Centre, 125 Coldharbour Lane, London SE5 9NU, UK
| | - David Killock
- BHF Centre for Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, James Black Centre, 125 Coldharbour Lane, London SE5 9NU, UK
| | - Maria Jesus Sanz
- Department of Pharmacology and Faculty of Medicine and Odontology, University of Valencia, Av. Blasco Ibáñez 15, 46010 Valencia, Spain.,Institute of Health Research INCLIVA, University Clinic Hospital of Valencia, Av. Menéndez Pelayo 4, 46010, Valencia, Spain.,CIBERDEM-Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders, ISCIII, Av. Monforte de Lemos 3-5, 28029, Madrid, Spain
| | - Guillaume Charras
- London Centre for Nanotechnology, University College London, London WC1H 0AH, UK
| | - Maddy Parsons
- Randall Centre for Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, UK
| | - Aleksandar Ivetic
- BHF Centre for Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, James Black Centre, 125 Coldharbour Lane, London SE5 9NU, UK
| |
Collapse
|
2
|
Newe A, Rzeniewicz K, König M, Schroer CFE, Joachim J, Rey-Gallardo A, Marrink SJ, Deka J, Parsons M, Ivetic A. Serine Phosphorylation of L-Selectin Regulates ERM Binding, Clustering, and Monocyte Protrusion in Transendothelial Migration. Front Immunol 2019; 10:2227. [PMID: 31608057 PMCID: PMC6774396 DOI: 10.3389/fimmu.2019.02227] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Accepted: 09/03/2019] [Indexed: 12/15/2022] Open
Abstract
The migration of circulating leukocytes toward damaged tissue is absolutely fundamental to the inflammatory response, and transendothelial migration (TEM) describes the first cellular barrier that is breached in this process. Human CD14+ inflammatory monocytes express L-selectin, bestowing a non-canonical role in invasion during TEM. In vivo evidence supports a role for L-selectin in regulating TEM and chemotaxis, but the intracellular mechanism is poorly understood. The ezrin-radixin-moesin (ERM) proteins anchor transmembrane proteins to the cortical actin-based cytoskeleton and additionally act as signaling adaptors. During TEM, the L-selectin tail within transmigrating pseudopods interacts first with ezrin to transduce signals for protrusion, followed by moesin to drive ectodomain shedding of L-selectin to limit protrusion. Collectively, interaction of L-selectin with ezrin and moesin fine-tunes monocyte protrusive behavior in TEM. Using FLIM/FRET approaches, we show that ERM binding is absolutely required for outside-in L-selectin clustering. The cytoplasmic tail of human L-selectin contains two serine (S) residues at positions 364 and 367, and here we show that they play divergent roles in regulating ERM binding. Phospho-S364 blocks direct interaction with ERM, whereas molecular modeling suggests phospho-S367 likely drives desorption of the L-selectin tail from the inner leaflet of the plasma membrane to potentiate ERM binding. Serine-to-alanine mutagenesis of S367, but not S364, significantly reduced monocyte protrusive behavior in TEM under flow conditions. Our data propose a model whereby L-selectin tail desorption from the inner leaflet of the plasma membrane and ERM binding are two separable steps that collectively regulate protrusive behavior in TEM.
Collapse
Affiliation(s)
- Abigail Newe
- BHF Centre of Research Excellence, James Black Centre, King's College London, London, United Kingdom
| | - Karolina Rzeniewicz
- BHF Centre of Research Excellence, James Black Centre, King's College London, London, United Kingdom
| | - Melanie König
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, Netherlands
| | - Carsten F E Schroer
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, Netherlands
| | - Justin Joachim
- BHF Centre of Research Excellence, James Black Centre, King's College London, London, United Kingdom
| | - Angela Rey-Gallardo
- BHF Centre of Research Excellence, James Black Centre, King's College London, London, United Kingdom
| | - Siewert J Marrink
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, Netherlands
| | - Jürgen Deka
- European Molecular Biology Laboratory, Heidelberg, Germany
| | - Maddy Parsons
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Aleksandar Ivetic
- BHF Centre of Research Excellence, James Black Centre, King's College London, London, United Kingdom
| |
Collapse
|
3
|
Muller WA. Transendothelial migration: unifying principles from the endothelial perspective. Immunol Rev 2017; 273:61-75. [PMID: 27558328 DOI: 10.1111/imr.12443] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Transendothelial migration (TEM) of polymorphonuclear leukocytes (PMN) involves a carefully orchestrated dialog of adhesion and signaling events between leukocyte and endothelial cell. This article focuses on the contribution of endothelial cells to transmigration. The initiation of TEM itself generally requires interaction of PECAM on the leukocyte with PECAM at the endothelial cell border. This is responsible for the transient elevation of cytosolic-free calcium ions in endothelium that is required for TEM and for recruitment of membrane from the lateral border recycling compartment (LBRC). TEM requires LBRC to move to the site at which TEM will take place and for VE-cadherin to move away. Targeting of the LBRC to this site likely precedes movement of VE-cadherin and may play a role in clearing VE-cadherin from the site of TEM. The process of TEM can be dissected into steps mediated by distinct pairs of PMN/endothelial interacting molecules. CD99 regulates a step at or close to the end of TEM. CD99 signals through soluble adenylyl cyclase to activate PKA to trigger ongoing targeted recycling of the LBRC. Paracellular transmigration predominates (≥90% of events) in the cremaster muscle circulation, but transcellular migration may be more important at sites such as the blood-brain barrier. Both processes involve many of the same molecules and recruitment of the LBRC.
Collapse
Affiliation(s)
- William A Muller
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| |
Collapse
|
4
|
Gonzalez AM, Cyrus BF, Muller WA. Targeted Recycling of the Lateral Border Recycling Compartment Precedes Adherens Junction Dissociation during Transendothelial Migration. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:1387-402. [PMID: 26968345 DOI: 10.1016/j.ajpath.2016.01.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 12/24/2015] [Accepted: 01/12/2016] [Indexed: 12/11/2022]
Abstract
Leukocyte transendothelial migration (TEM) requires two major events: local dissociation of adherens junctions manifested as gaps in vascular endothelial (VE)-cadherin staining at the site of TEM and targeted trafficking of the lateral border recycling compartment (LBRC) to the site of TEM. However, the association between LBRC recycling and VE-cadherin gaps remains unknown. We found that when targeting of the LBRC is selectively inhibited using established methods, such as a function blocking anti-platelet endothelial cell adhesion molecule 1 antibody, depolymerizing microtubules, or microinjection of an antibody that inhibits kinesin, VE-cadherin gaps do not form around the blocked leukocyte. This is the first time that the LBRC has been implicated in this process. We obtained similar results for neutrophils and monocytes and in studies using live cell imaging microscopy conducted under fluid shear conditions. Depolymerizing microtubules did not affect the ability of leukocytes to induce tyrosine phosphorylation of VE-cadherin. A VE-cadherin double mutant (Y658F, Y731F) expressed in endothelial cells acted as a dominant negative and inhibited VE-cadherin gap formation and TEM, yet targeting of the LBRC still occurred. These data suggest that targeting of the LBRC to the site of TEM precedes VE-cadherin clearance. Recruitment of the LBRC may play a role in clearing VE-cadherin from the site of TEM.
Collapse
Affiliation(s)
- Annette M Gonzalez
- Department of Pathology, The Feinberg School of Medicine at Northwestern University, Chicago, Illinois
| | - Bita F Cyrus
- Department of Pathology, The Feinberg School of Medicine at Northwestern University, Chicago, Illinois
| | - William A Muller
- Department of Pathology, The Feinberg School of Medicine at Northwestern University, Chicago, Illinois.
| |
Collapse
|
5
|
Newman DK, Fu G, Adams T, Cui W, Arumugam V, Bluemn T, Riese MJ. The adhesion molecule PECAM-1 enhances the TGF-β-mediated inhibition of T cell function. Sci Signal 2016; 9:ra27. [PMID: 26956486 DOI: 10.1126/scisignal.aad1242] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Transforming growth factor-β (TGF-β) is an immunosuppressive cytokine that inhibits the proinflammatory functions of T cells, and it is a major factor in abrogating T cell activity against tumors. Canonical TGF-β signaling results in the activation of Smad proteins, which are transcription factors that regulate target gene expression. We found that the cell surface molecule platelet endothelial cell adhesion molecule-1 (PECAM-1) facilitated noncanonical (Smad-independent) TGF-β signaling in T cells. Subcutaneously injected tumor cells that are dependent on TGF-β-mediated suppression of immunity for growth grew more slowly in PECAM-1(-/-) mice than in their wild-type counterparts. T cells isolated from PECAM-1(-/-) mice demonstrated relative insensitivity to the TGF-β-dependent inhibition of interferon-γ (IFN-γ) production, granzyme B synthesis, and cellular proliferation. Similarly, human T cells lacking PECAM-1 demonstrated decreased sensitivity to TGF-β in a manner that was partially restored by reexpression of PECAM-1. Co-incubation of T cells with TGF-β and a T cell-activating antibody resulted in PECAM-1 phosphorylation on an immunoreceptor tyrosine-based inhibitory motif (ITIM) and the recruitment of the inhibitory Src homology 2 (SH2) domain-containing tyrosine phosphatase-2 (SHP-2). Such conditions also induced the colocalization of PECAM-1 with the TGF-β receptor complex as identified by coimmunoprecipitation, confocal microscopy, and proximity ligation assays. These studies indicate a role for PECAM-1 in enhancing the inhibitory functions of TGF-β in T cells and suggest that therapeutic targeting of the PECAM-1-TGF-β inhibitory axis represents a means to overcome TGF-β-dependent immunosuppression within the tumor microenvironment.
Collapse
Affiliation(s)
- Debra K Newman
- Blood Research Institute, BloodCenter of Wisconsin, 8727 Watertown Plank Road, Milwaukee, WI 53226, USA. Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA. Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
| | - Guoping Fu
- Blood Research Institute, BloodCenter of Wisconsin, 8727 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Tamara Adams
- Blood Research Institute, BloodCenter of Wisconsin, 8727 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Weiguo Cui
- Blood Research Institute, BloodCenter of Wisconsin, 8727 Watertown Plank Road, Milwaukee, WI 53226, USA. Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Vidhyalakshmi Arumugam
- Blood Research Institute, BloodCenter of Wisconsin, 8727 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Theresa Bluemn
- Blood Research Institute, BloodCenter of Wisconsin, 8727 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Matthew J Riese
- Blood Research Institute, BloodCenter of Wisconsin, 8727 Watertown Plank Road, Milwaukee, WI 53226, USA. Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, WI 53226, USA. Division of Hematology and Oncology, Department of Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
| |
Collapse
|
6
|
Abstract
The hypothesis that the Golgi apparatus is capable of sorting proteins and sending them to the plasma membrane through "lipid rafts," membrane lipid domains highly enriched in glycosphingolipids, sphingomyelin, ceramide, and cholesterol, was formulated by van Meer and Simons in 1988 and came to a turning point when it was suggested that lipid rafts could be isolated thanks to their resistance to solubilization by some detergents, namely Triton X-100. An incredible number of papers have described the composition and properties of detergent-resistant membrane fractions. However, the use of this method has also raised the fiercest criticisms. In this chapter, we would like to discuss the most relevant methodological aspects related to the preparation of detergent-resistant membrane fractions, and to discuss the importance of discriminating between what is present on a cell membrane and what we can prepare from cell membranes in a laboratory tube.
Collapse
|
7
|
Muller WA. The regulation of transendothelial migration: new knowledge and new questions. Cardiovasc Res 2015; 107:310-20. [PMID: 25987544 PMCID: PMC4592322 DOI: 10.1093/cvr/cvv145] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 03/13/2015] [Accepted: 04/01/2015] [Indexed: 12/14/2022] Open
Abstract
Leucocyte transendothelial migration (TEM) involves a co-operative series of interactions between surface molecules on the leucocyte and cognate counter-ligands on the endothelial cell. These interactions set up a cascade of signalling events inside the endothelial cell that both allow for the junctions to loosen and for membrane to be recruited from the lateral border recycling compartment (LBRC). The LBRC is thought to provide an increased surface area and unligated receptors to the leucocyte to continue the process. The relative importance of the individual adhesion/signalling molecules that promote transmigration may vary depending on the type of leucocyte, the vascular bed, the inflammatory stimulus, and the stage of the inflammatory response. However, the molecular interactions between leucocyte and endothelial cell activate signalling pathways that disengage the adherens and tight junctions and recruit the LBRC to the site of transmigration. With the exception of disengaging the junctions, similar molecules and mechanisms promote transcellular migration as paracellular migration of leucocytes. This review will discuss the molecular interactions and signalling pathways that regulate transmigration, and the common themes that emerge from studying TEM of different leucocyte subsets under different inflammatory conditions. We will also raise some unanswered questions in need of future research.
Collapse
Affiliation(s)
- William A Muller
- Department of Pathology, Northwestern University Feinberg School of Medicine, Ward Building 3-140, 303 East Chicago Avenue, Chicago, IL 60611, USA
| |
Collapse
|
8
|
Yalak G, Ehrlich YH, Olsen BR. Ecto-protein kinases and phosphatases: an emerging field for translational medicine. J Transl Med 2014; 12:165. [PMID: 24923278 PMCID: PMC4071215 DOI: 10.1186/1479-5876-12-165] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 05/29/2014] [Indexed: 12/30/2022] Open
Abstract
Progress in translational research has led to effective new treatments of a large number of diseases. Despite this progress, diseases including cancer and cardiovascular disorders still are at the top in death statistics and disorders such as osteoporosis and osteoarthritis represent an increasing disease burden in the aging population. Novel strategies in research are needed more than ever to overcome such diseases. The growing field of extracellular protein phosphorylation provides excellent opportunities to make major discoveries of disease mechanisms that can lead to novel therapies. Reversible phosphorylation/dephosphorylation of sites in the extracellular domains of matrix, cell-surface and trans-membrane proteins is emerging as a critical regulatory mechanism in health and disease. Moreover, a new concept is emerging from studies of extracellular protein phosphorylation: in cells where ATP is stored within secretory vesicles and released by exocytosis upon cell-stimulation, phosphorylation of extracellular proteins can operate as a messenger operating uniquely in signaling pathways responsible for long-term cellular adaptation. Here, we highlight new concepts that arise from this research, and discuss translation of the findings into clinical applications such as development of diagnostic disease markers and next-generation drugs.
Collapse
Affiliation(s)
| | | | - Bjorn R Olsen
- Department of Developmental Biology, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, USA.
| |
Collapse
|
9
|
Sullivan DP, Muller WA. Neutrophil and monocyte recruitment by PECAM, CD99, and other molecules via the LBRC. Semin Immunopathol 2013; 36:193-209. [PMID: 24337626 DOI: 10.1007/s00281-013-0412-6] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 11/28/2013] [Indexed: 12/14/2022]
Abstract
The recruitment of specific leukocyte subtypes to the site of tissue injury is the cornerstone of inflammation and disease progression. This process has become an intense area of research because it presents several possible steps against which disease-specific therapies could be targeted. Leukocytes are recruited out of the blood stream by a series of events that include their capture, rolling, activation, and migration along the endothelium. In the last step, the leukocytes squeeze between adjacent endothelial cells to gain access to the inflamed tissue through a process referred to as transendothelial migration (TEM). Although many of the molecules, such as PECAM and CD99, that regulate these sequential steps have been identified, much less is understood regarding how they work together to coordinate the complex intercellular communications and dramatic shape changes that take place between the endothelial cells and leukocytes. Several of the endothelial cell proteins that function in TEM are localized to the lateral border recycling compartment (LBRC), an interconnected reticulum of membrane that recycles selectively to the endothelial borders. The recruitment of the LBRC to surround the migrating leukocyte is required for efficient TEM. This review will focus on the proteins and mechanisms that mediate TEM and specifically how the LBRC functions in the context of these molecular interactions and membrane movements.
Collapse
Affiliation(s)
- David P Sullivan
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Ward Building, Rm 3-140, 303 E. Chicago Ave, Chicago, IL, 60611, USA
| | | |
Collapse
|
10
|
Subramani J, Ghosh M, Rahman MM, Caromile LA, Gerber C, Rezaul K, Han DK, Shapiro LH. Tyrosine phosphorylation of CD13 regulates inflammatory cell-cell adhesion and monocyte trafficking. THE JOURNAL OF IMMUNOLOGY 2013; 191:3905-12. [PMID: 23997214 DOI: 10.4049/jimmunol.1301348] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
CD13 is a large cell surface peptidase expressed on the monocytes and activated endothelial cells that is important for homing to and resolving the damaged tissue at sites of injury. We showed previously that cross-linking of human monocytic CD13 with activating Abs induces strong adhesion to endothelial cells in a tyrosine kinase- and microtubule-dependent manner. In the current study, we examined the molecular mechanisms underlying these observations in vitro and in vivo. We found that cross-linking of CD13 on U937 monocytic cells induced phosphorylation of a number of proteins, including Src, FAK, and ERK, and inhibition of these abrogated CD13-dependent adhesion. We found that CD13 itself was phosphorylated in a Src-dependent manner, which was an unexpected finding because its 7-aa cytoplasmic tail was assumed to be inert. Furthermore, CD13 was constitutively associated with the scaffolding protein IQGAP1, and CD13 cross-linking induced complex formation with the actin-binding protein α-actinin, linking membrane-bound CD13 to the cytoskeleton, further supporting CD13 as an inflammatory adhesion molecule. Mechanistically, mutation of the conserved CD13 cytoplasmic tyrosine to phenylalanine abrogated adhesion; Src, FAK, and ERK phosphorylation; and cytoskeletal alterations upon Ab cross-linking. Finally, CD13 was phosphorylated in isolated murine inflammatory peritoneal exudate cells, and adoptive transfer of monocytic cell lines engineered to express the mutant CD13 were severely impaired in their ability to migrate into the inflamed peritoneum, confirming that CD13 phosphorylation is relevant to inflammatory cell trafficking in vivo. Therefore, this study identifies CD13 as a novel, direct activator of intracellular signaling pathways in pathophysiological conditions.
Collapse
Affiliation(s)
- Jaganathan Subramani
- Center for Vascular Biology, University of Connecticut Health Center, Farmington, CT 06030
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Marchese ME, Berdnikovs S, Cook-Mills JM. Distinct sites within the vascular cell adhesion molecule-1 (VCAM-1) cytoplasmic domain regulate VCAM-1 activation of calcium fluxes versus Rac1 during leukocyte transendothelial migration. Biochemistry 2012; 51:8235-46. [PMID: 22970700 DOI: 10.1021/bi300925r] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Vascular adhesion molecules regulate the migration of leukocytes from the blood into tissue during inflammation. Binding of leukocytes to vascular cell adhesion molecule-1 (VCAM-1) activates signals in endothelial cells, including Rac1 and calcium fluxes. These VCAM-1 signals are required for leukocyte transendothelial migration on VCAM-1. However, it has not been reported whether the cytoplasmic domain of VCAM-1 is necessary for these signals. Interestingly, the 19-amino acid sequence of the VCAM-1 cytoplasmic domain is 100% conserved among many mammalian species, suggesting an important functional role for the domain. To examine the function of the VCAM-1 cytoplasmic domain, we deleted the VCAM-1 cytoplasmic domain or mutated the cytoplasmic domain at amino acid N724, S728, Y729, S730, or S737. The cytoplasmic domain and S728, Y729, S730, or S737 were necessary for leukocyte transendothelial migration. S728 and Y729, but not S730 or S737, were necessary for VCAM-1 activation of calcium fluxes. In contrast, S730 and S737, but not S728 or Y729, were necessary for VCAM-1 activation of Rac1. These functional data are consistent with our computational model of the structure of the VCAM-1 cytoplasmic domain as an α-helix with S728 and Y729, and S730 and S737, on opposite sides of the α-helix. Together, these data indicate that S728 and Y729, and S730 and S737, are distinct functional sites that coordinate VCAM-1 activation of calcium fluxes and Rac1 during leukocyte transendothelial migration.
Collapse
Affiliation(s)
- Michelle E Marchese
- Division of Allergy and Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | | | | |
Collapse
|
12
|
Fernández-Martín L, Marcos-Ramiro B, Bigarella CL, Graupera M, Cain RJ, Reglero-Real N, Jiménez A, Cernuda-Morollón E, Correas I, Cox S, Ridley AJ, Millán J. Crosstalk between reticular adherens junctions and platelet endothelial cell adhesion molecule-1 regulates endothelial barrier function. Arterioscler Thromb Vasc Biol 2012; 32:e90-102. [PMID: 22723439 DOI: 10.1161/atvbaha.112.252080] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Endothelial cells provide a barrier between the blood and tissues, which is reduced during inflammation to allow selective passage of molecules and cells. Adherens junctions (AJ) play a central role in regulating this barrier. We aim to investigate the role of a distinctive 3-dimensional reticular network of AJ found in the endothelium. METHODS AND RESULTS In endothelial AJ, vascular endothelial-cadherin recruits the cytoplasmic proteins β-catenin and p120-catenin. β-catenin binds to α-catenin, which links AJ to actin filaments. AJ are usually described as linear structures along the actin-rich intercellular contacts. Here, we show that these AJ components can also be organized in reticular domains that contain low levels of actin. Reticular AJ are localized in areas where neighboring cells overlap and encompass the cell adhesion receptor platelet endothelial cell adhesion molecule-1 (PECAM-1). Superresolution microscopy revealed that PECAM-1 forms discrete structures distinct from and distributed along AJ, within the voids of reticular domains. Inflammatory tumor necrosis factor-α increases permeability by mechanisms that are independent of actomyosin-mediated tension and remain incompletely understood. Reticular AJ, but not actin-rich linear AJ, were disorganized by tumor necrosis factor-α. This correlated with PECAM-1 dispersal from cell borders. PECAM-1 inhibition with blocking antibodies or small interfering RNA specifically disrupted reticular AJ, leaving linear AJ intact. This disruption recapitulated typical tumor necrosis factor-α-induced alterations of barrier function, including increased β-catenin phosphorylation, without altering the actomyosin cytoskeleton. CONCLUSIONS We propose that reticular AJ act coordinately with PECAM-1 to maintain endothelial barrier function in regions of low actomyosin-mediated tension. Selective disruption of reticular AJ contributes to permeability increase in response to tumor necrosis factor-α.
Collapse
Affiliation(s)
- Laura Fernández-Martín
- Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Privratsky JR, Paddock CM, Florey O, Newman DK, Muller WA, Newman PJ. Relative contribution of PECAM-1 adhesion and signaling to the maintenance of vascular integrity. J Cell Sci 2011; 124:1477-85. [PMID: 21486942 DOI: 10.1242/jcs.082271] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PECAM-1 (CD31) is a cellular adhesion and signaling receptor that is highly expressed at endothelial cell-cell junctions in confluent vascular beds. Previous studies have implicated PECAM-1 in the maintenance of vascular barrier integrity; however, the mechanisms behind PECAM-1-mediated barrier protection are still poorly understood. The goal of the present study, therefore, was to examine the pertinent biological properties of PECAM-1 (i.e. adhesion and/or signaling) that allow it to support barrier integrity. We found that, compared with PECAM-1-deficient endothelial cells, PECAM-1-expressing endothelial cell monolayers exhibit increased steady-state barrier function, as well as more rapid restoration of barrier integrity following thrombin-induced perturbation of the endothelial cell monolayer. The majority of PECAM-1-mediated barrier protection was found to be due to the ability of PECAM-1 to interact homophilically and become localized to cell-cell junctions, because a homophilic binding-crippled mutant form of PECAM-1 was unable to support efficient barrier function when re-expressed in cells. By contrast, cells expressing PECAM-1 variants lacking residues known to be involved in PECAM-1-mediated signal transduction exhibited normal to near-normal barrier integrity. Taken together, these studies suggest that PECAM-1-PECAM-1 homophilic interactions are more important than its signaling function for maintaining the integrity of endothelial cell junctions.
Collapse
Affiliation(s)
- Jamie R Privratsky
- Blood Research Institute, Blood Center of Wisconsin, Milwaukee, WI 53201, USA
| | | | | | | | | | | |
Collapse
|
14
|
Lo Buono N, Parrotta R, Morone S, Bovino P, Nacci G, Ortolan E, Horenstein AL, Inzhutova A, Ferrero E, Funaro A. The CD157-integrin partnership controls transendothelial migration and adhesion of human monocytes. J Biol Chem 2011; 286:18681-91. [PMID: 21478153 DOI: 10.1074/jbc.m111.227876] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
CD157, a member of the CD38 gene family, is an NAD-metabolizing ectoenzyme and a signaling molecule whose role in polarization, migration, and diapedesis of human granulocytes has been documented; however, the molecular events underpinning this role remain to be elucidated. This study focused on the role exerted by CD157 in monocyte migration across the endothelial lining and adhesion to extracellular matrix proteins. The results demonstrated that anti-CD157 antibodies block monocyte transmigration and adhesion to fibronectin and fibrinogen but that CD157 cross-linking is sufficient to overcome the block, suggesting an active signaling role for the molecule. Consistent with this is the observation that CD157 is prevalently located within the detergent-resistant membrane microdomains to which, upon clustering, it promotes the recruitment of β(1) and β(2) integrin, which, in turn, leads to the formation of a multimolecular complex favoring signal transduction. This functional cross-talk with integrins allows CD157 to act as a receptor despite its intrinsic structural inability to do so on its own. Intracellular signals mediated by CD157 rely on the integrin/Src/FAK (focal adhesion kinase) pathway, resulting in increased activity of the MAPK/ERK1/2 and the PI3K/Akt downstream signaling pathways, which are crucial in the control of monocyte transendothelial migration. Collectively, these findings indicate that CD157 acts as a molecular organizer of signaling-competent membrane microdomains and that it forms part of a larger molecular machine ruled by integrins. The CD157-integrin partnership provides optimal adhesion and transmigration of human monocytes.
Collapse
Affiliation(s)
- Nicola Lo Buono
- Laboratory of Immunogenetics, Department of Genetics, University of Torino Medical School, 10126 Torino, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|