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Luissint AC, Fan S, Nishio H, Lerario AM, Miranda J, Hilgarth RS, Cook J, Nusrat A, Parkos CA. CXADR-Like Membrane Protein Regulates Colonic Epithelial Cell Proliferation and Prevents Tumor Growth. Gastroenterology 2024; 166:103-116.e9. [PMID: 37716376 DOI: 10.1053/j.gastro.2023.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 08/23/2023] [Accepted: 09/01/2023] [Indexed: 09/18/2023]
Abstract
BACKGROUND & AIMS CXADR-like membrane protein (CLMP) is structurally related to coxsackie and adenovirus receptor. Pathogenic variants in CLMP gene have been associated with congenital short bowel syndrome, implying a role for CLMP in intestinal development. However, the contribution of CLMP to regulating gut development and homeostasis is unknown. METHODS In this study, we investigated CLMP function in the colonic epithelium using complementary in vivo and in vitro approaches, including mice with inducible intestinal epithelial cell (IEC)-specific deletion of CLMP (ClmpΔIEC), intestinal organoids, IECs with overexpression, or loss of CLMP and RNA sequencing data from individuals with colorectal cancer. RESULTS Loss of CLMP enhanced IEC proliferation and, conversely, CLMP overexpression reduced proliferation. Xenograft experiments revealed increased tumor growth in mice implanted with CLMP-deficient colonic tumor cells, and poor engraftment was observed with CLMP-overexpressing cells. ClmpΔIEC mice showed exacerbated tumor burden in an azoxymethane and dextran sulfate sodium-induced colonic tumorigenesis model, and CLMP expression was reduced in human colorectal cancer samples. Mechanistic studies revealed that CLMP-dependent regulation of IEC proliferation is linked to signaling through mTOR-Akt-β-catenin pathways. CONCLUSIONS These results reveal novel insights into CLMP function in the colonic epithelium, highlighting an important role in regulating IEC proliferation, suggesting tumor suppressive function in colon cancer.
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Affiliation(s)
| | - Shuling Fan
- Department of Pathology, University of Michigan, Ann Arbor, Michigan
| | - Hikaru Nishio
- Department of Pathology, Emory University, Atlanta, Georgia
| | - Antonio M Lerario
- Department of Internal Medicine, Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, Michigan
| | - Jael Miranda
- Department of Pathology, University of Michigan, Ann Arbor, Michigan
| | - Roland S Hilgarth
- Department of Pathology, University of Michigan, Ann Arbor, Michigan
| | - Jonas Cook
- Department of Pathology, University of Michigan, Ann Arbor, Michigan
| | - Asma Nusrat
- Department of Pathology, University of Michigan, Ann Arbor, Michigan.
| | - Charles A Parkos
- Department of Pathology, University of Michigan, Ann Arbor, Michigan.
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2
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Raya-Sandino A, Lozada-Soto KM, Rajagopal N, Garcia-Hernandez V, Luissint AC, Brazil JC, Cui G, Koval M, Parkos CA, Nangia S, Nusrat A. Claudin-23 reshapes epithelial tight junction architecture to regulate barrier function. Nat Commun 2023; 14:6214. [PMID: 37798277 PMCID: PMC10556055 DOI: 10.1038/s41467-023-41999-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 09/26/2023] [Indexed: 10/07/2023] Open
Abstract
Claudin family tight junction proteins form charge- and size-selective paracellular channels that regulate epithelial barrier function. In the gastrointestinal tract, barrier heterogeneity is attributed to differential claudin expression. Here, we show that claudin-23 (CLDN23) is enriched in luminal intestinal epithelial cells where it strengthens the epithelial barrier. Complementary approaches reveal that CLDN23 regulates paracellular ion and macromolecule permeability by associating with CLDN3 and CLDN4 and regulating their distribution in tight junctions. Computational modeling suggests that CLDN23 forms heteromeric and heterotypic complexes with CLDN3 and CLDN4 that have unique pore architecture and overall net charge. These computational simulation analyses further suggest that pore properties are interaction-dependent, since differently organized complexes with the same claudin stoichiometry form pores with unique architecture. Our findings provide insight into tight junction organization and propose a model whereby different claudins combine to form multiple distinct complexes that modify epithelial barrier function by altering tight junction structure.
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Affiliation(s)
- Arturo Raya-Sandino
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Nandhini Rajagopal
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, USA
| | | | - Anny-Claude Luissint
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Jennifer C Brazil
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Guiying Cui
- Department of Pediatrics, Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine, Atlanta, GA, USA
| | - Michael Koval
- Departments of Medicine and Cell Biology, Emory University School of Medicine, Atlanta, GA, USA
| | - Charles A Parkos
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Shikha Nangia
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, USA.
| | - Asma Nusrat
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, USA.
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3
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Azcutia V, Kelm M, Kim S, Luissint AC, Flemming S, Abernathy-Close L, Young VB, Nusrat A, Miller MJ, Parkos CA. Distinct stimulus-dependent neutrophil dynamics revealed by real-time imaging of intestinal mucosa after acute injury. PNAS Nexus 2022; 1:pgac249. [PMID: 36712325 PMCID: PMC9802210 DOI: 10.1093/pnasnexus/pgac249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022]
Abstract
Clinical symptoms in many inflammatory diseases of the intestine are directly related to neutrophil (PMN) migration across colonic mucosa and into the intestinal lumen, yet in-vivo studies detailing this process are lacking. Using real-time intravital microscopy and a new distal colon loop model, we report distinct PMN migratory dynamics in response to several models of acute colonic injury. PMNs exhibited rapid swarming responses after mechanically induced intestinal wounds. Similar numbers of PMNs infiltrated colonic mucosa after wounding in germ-free mice, suggesting microbiota-independent mechanisms. By contrast, acute mucosal injury secondary to either a treatment of mice with dextran sodium sulfate or an IL-10 receptor blockade model of colitis resulted in lamina propria infiltration with PMNs that were largely immotile. Biopsy wounding of colonic mucosa in DSS-treated mice did not result in enhanced PMN swarming however, intraluminal application of the neutrophil chemoattractant LTB4 under such conditions resulted in enhanced transepithelial migration of PMNs. Analyses of PMNs that had migrated into the colonic lumen revealed that the majority of PMNs were directly recruited from the circulation and not from the immotile pool in the mucosa. Decreased PMN motility parallels upregulation of the receptor CXCR4 and apoptosis. Similarly, increased expression of CXCR4 on human PMNs was observed in colonic biopsies from people with active ulcerative colitis. This new approach adds an important tool to investigate mechanisms regulating PMN migration across mucosa within the distal intestine and will provide new insights for developing future anti-inflammatory and pro-repair therapies.
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Affiliation(s)
- Veronica Azcutia
- Department of Pathology, University of Michigan; Ann Arbor, MI 48109, USA
| | - Matthias Kelm
- Department of Pathology, University of Michigan; Ann Arbor, MI 48109, USA
| | - Seonyoung Kim
- Department of Internal Medicine, Washington University School of Medicine; Saint Louis, MO 63110, USA
| | | | - Sven Flemming
- Department of Pathology, University of Michigan; Ann Arbor, MI 48109, USA
| | - Lisa Abernathy-Close
- Department of Internal Medicine/Division of Infectious Diseases, University of Michigan; Ann Arbor, MI 48109, USA
| | - Vincent B Young
- Department of Internal Medicine/Division of Infectious Diseases, University of Michigan; Ann Arbor, MI 48109, USA.,Department of Microbiology and Immunology, University of Michigan; Ann Arbor, MI 48109, USA
| | - Asma Nusrat
- Department of Pathology, University of Michigan; Ann Arbor, MI 48109, USA
| | - Mark J Miller
- Department of Internal Medicine, Washington University School of Medicine; Saint Louis, MO 63110, USA
| | - Charles A Parkos
- Department of Pathology, University of Michigan; Ann Arbor, MI 48109, USA
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4
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Azcutia V, Kelm M, Luissint AC, Boerner K, Flemming S, Quiros M, Newton G, Nusrat A, Luscinskas FW, Parkos CA. Neutrophil expressed CD47 regulates CD11b/CD18-dependent neutrophil transepithelial migration in the intestine in vivo. Mucosal Immunol 2021; 14:331-341. [PMID: 32561828 PMCID: PMC7749029 DOI: 10.1038/s41385-020-0316-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/24/2020] [Accepted: 06/04/2020] [Indexed: 02/04/2023]
Abstract
Dysregulated neutrophil (PMN) transmigration across epithelial surfaces (TEpM) significantly contributes to chronic inflammatory diseases, yet mechanisms defining this process remain poorly understood. In the intestine, uncontrolled PMN TEpM is a hallmark of disease flares in ulcerative colitis. Previous in vitro studies directed at identifying molecular determinants that mediate TEpM have shown that plasma membrane proteins including CD47 and CD11b/CD18 play key roles in regulating PMN TEpM across monolayers of intestinal epithelial cells. Here, we show that CD47 modulates PMN TEpM in vivo using an ileal loop assay. Importantly, using novel tissue-specific CD47 knockout mice and in vitro approaches, we report that PMN-expressed, but not epithelial-expressed CD47 plays a major role in regulating PMN TEpM. We show that CD47 associates with CD11b/CD18 in the plasma membrane of PMN, and that loss of CD47 results in impaired CD11b/CD18 activation. In addition, in vitro and in vivo studies using function blocking antibodies support a role of CD47 in regulating CD11b-dependent PMN TEpM and chemotaxis. Taken together, these findings provide new insights for developing approaches to target dysregulated PMN infiltration in the intestine. Moreover, tissue-specific CD47 knockout mice constitute an important new tool to study contributions of cells expressing CD47 to inflammation in vivo.
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Affiliation(s)
- Veronica Azcutia
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA.,Correspondence to:Veronica Azcutia, PhD. Department of Pathology, University of Michigan School of Medicine, 109 Zina Pitcher, BSRB Rm-4620. Ann Arbor, Michigan 48109, USA. Tel: (734) 936-1856 ; Charles A. Parkos, MD, PhD. Department of Pathology, University of Michigan School of Medicine, 2800 Plymouth Road, NCRC 30-1537. Ann Arbor, Michigan 48109, USA. Tel: (734) 763-6384 Fax: (734) 763-4782
| | - Matthias Kelm
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Anny-Claude Luissint
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Kevin Boerner
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Sven Flemming
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Miguel Quiros
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Gail Newton
- Center for Excellence in Vascular Biology, Department of Pathology, Brigham and Women’s Hospital, Boston, MA 02115, USA.,Harvard Medical School, Boston, MA 02115, USA
| | - Asma Nusrat
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Francis W. Luscinskas
- Center for Excellence in Vascular Biology, Department of Pathology, Brigham and Women’s Hospital, Boston, MA 02115, USA.,Harvard Medical School, Boston, MA 02115, USA
| | - Charles A. Parkos
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA.,Correspondence to:Veronica Azcutia, PhD. Department of Pathology, University of Michigan School of Medicine, 109 Zina Pitcher, BSRB Rm-4620. Ann Arbor, Michigan 48109, USA. Tel: (734) 936-1856 ; Charles A. Parkos, MD, PhD. Department of Pathology, University of Michigan School of Medicine, 2800 Plymouth Road, NCRC 30-1537. Ann Arbor, Michigan 48109, USA. Tel: (734) 763-6384 Fax: (734) 763-4782
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5
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Raya-Sandino A, Luissint AC, Kusters DHM, Narayanan V, Flemming S, Garcia-Hernandez V, Godsel LM, Green KJ, Hagen SJ, Conway DE, Parkos CA, Nusrat A. Regulation of intestinal epithelial intercellular adhesion and barrier function by desmosomal cadherin desmocollin-2. Mol Biol Cell 2021; 32:753-768. [PMID: 33596089 PMCID: PMC8108520 DOI: 10.1091/mbc.e20-12-0775] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The role of desmosomal cadherin desmocollin-2 (Dsc2) in regulating barrier function in intestinal epithelial cells (IECs) is not well understood. Here, we report the consequences of silencing Dsc2 on IEC barrier function in vivo using mice with inducible intestinal–epithelial-specific Dsc2 knockdown (KD) (Dsc2ERΔIEC). While the small intestinal gross architecture was maintained, loss of epithelial Dsc2 influenced desmosomal plaque structure, which was smaller in size and had increased intermembrane space between adjacent epithelial cells. Functional analysis revealed that loss of Dsc2 increased intestinal permeability in vivo, supporting a role for Dsc2 in the regulation of intestinal epithelial barrier function. These results were corroborated in model human IECs in which Dsc2 KD resulted in decreased cell–cell adhesion and impaired barrier function. It is noteworthy that Dsc2 KD cells exhibited delayed recruitment of desmoglein-2 (Dsg2) to the plasma membrane after calcium switch-induced intercellular junction reassembly, while E-cadherin accumulation was unaffected. Mechanistically, loss of Dsc2 increased desmoplakin (DP I/II) protein expression and promoted intermediate filament interaction with DP I/II and was associated with enhanced tension on desmosomes as measured by a Dsg2-tension sensor. In conclusion, we provide new insights on Dsc2 regulation of mechanical tension, adhesion, and barrier function in IECs.
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Affiliation(s)
- Arturo Raya-Sandino
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Anny-Claude Luissint
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Dennis H M Kusters
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Vani Narayanan
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA 23284
| | - Sven Flemming
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI 48109
| | | | - Lisa M Godsel
- Departments of Pathology and Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Kathleen J Green
- Departments of Pathology and Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611.,Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Chicago, IL 60611
| | - Susan J Hagen
- Department of Surgery, Beth Israel Deaconess Medical Center, Boston, MA 02115
| | - Daniel E Conway
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA 23284
| | - Charles A Parkos
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Asma Nusrat
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI 48109
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6
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Boerner K, Luissint AC, Parkos CA. Functional Assessment of Intestinal Permeability and Neutrophil Transepithelial Migration in Mice using a Standardized Intestinal Loop Model. J Vis Exp 2021. [PMID: 33645571 DOI: 10.3791/62093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The intestinal mucosa is lined by a single layer of epithelial cells that forms a dynamic barrier allowing paracellular transport of nutrients and water while preventing passage of luminal bacteria and exogenous substances. A breach of this layer results in increased permeability to luminal contents and recruitment of immune cells, both of which are hallmarks of pathologic states in the gut including inflammatory bowel disease (IBD). Mechanisms regulating epithelial barrier function and transepithelial migration (TEpM) of polymorphonuclear neutrophils (PMN) are incompletely understood due to the lack of experimental in vivo methods allowing quantitative analyses. Here, we describe a robust murine experimental model that employs an exteriorized intestinal segment of either ileum or proximal colon. The exteriorized intestinal loop (iLoop) is fully vascularized and offers physiological advantages over ex vivo chamber-based approaches commonly used to study permeability and PMN migration across epithelial cell monolayers. We demonstrate two applications of this model in detail: (1) quantitative measurement of intestinal permeability through detection of fluorescence-labeled dextrans in serum after intraluminal injection, (2) quantitative assessment of migrated PMN across the intestinal epithelium into the gut lumen after intraluminal introduction of chemoattractants. We demonstrate feasibility of this model and provide results utilizing the iLoop in mice lacking the epithelial tight junction-associated protein JAM-A compared to controls. JAM-A has been shown to regulate epithelial barrier function as well as PMN TEpM during inflammatory responses. Our results using the iLoop confirm previous studies and highlight the importance of JAM-A in regulation of intestinal permeability and PMN TEpM in vivo during homeostasis and disease. The iLoop model provides a highly standardized method for reproducible in vivo studies of intestinal homeostasis and inflammation and will significantly enhance understanding of intestinal barrier function and mucosal inflammation in diseases such as IBD.
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Affiliation(s)
- Kevin Boerner
- Department of Pathology, University of Michigan, Ann Arbor
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7
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Raya-Sandino A, Kusters DH, Luissint AC, Conway DE, Narayanan V, Hagen SJ, Smith KH, Flemming S, Garcia-Hernandez V, Yulis M, Parkos CA, Nusrat A. Differential Regulation of Intestinal Epithelial Intercellular Adhesion and Barrier Function by Desmosomal Cadherins. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.07219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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8
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Flemming S, Luissint AC, Kusters DHM, Raya-Sandino A, Fan S, Zhou DW, Hasegawa M, Garcia-Hernandez V, García AJ, Parkos CA, Nusrat A. Desmocollin-2 promotes intestinal mucosal repair by controlling integrin-dependent cell adhesion and migration. Mol Biol Cell 2020; 31:407-418. [PMID: 31967937 PMCID: PMC7185897 DOI: 10.1091/mbc.e19-12-0692] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The intestinal mucosa is lined by a single layer of epithelial cells that forms a tight barrier, separating luminal antigens and microbes from underlying tissue compartments. Mucosal damage results in a compromised epithelial barrier that can lead to excessive immune responses as observed in inflammatory bowel disease. Efficient wound repair is critical to reestablish the mucosal barrier and homeostasis. Intestinal epithelial cells (IEC) exclusively express the desmosomal cadherins, Desmoglein-2 and Desmocollin-2 (Dsc2) that contribute to mucosal homeostasis by strengthening intercellular adhesion between cells. Despite this important property, specific contributions of desmosomal cadherins to intestinal mucosal repair after injury remain poorly investigated in vivo. Here we show that mice with inducible conditional knockdown (KD) of Dsc2 in IEC (Villin-CreERT2; Dsc2 fl/fl) exhibited impaired mucosal repair after biopsy-induced colonic wounding and recovery from dextran sulfate sodium-induced colitis. In vitro analyses using human intestinal cell lines after KD of Dsc2 revealed delayed epithelial cell migration and repair after scratch-wound healing assay that was associated with reduced cell–matrix traction forces, decreased levels of integrin β1 and β4, and altered activity of the small GTPase Rap1. Taken together, these results demonstrate that epithelial Dsc2 is a key contributor to intestinal mucosal wound healing in vivo.
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Affiliation(s)
- Sven Flemming
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | | | | | | | - Shuling Fan
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | - Dennis W Zhou
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332
| | - Mizuho Hasegawa
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | | | - Andrés J García
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332.,Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA 30332
| | - Charles A Parkos
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | - Asma Nusrat
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
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9
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Luissint AC, Williams HC, Kim W, Flemming S, Azcutia V, Hilgarth RS, Leary MNO, Denning TL, Nusrat A, Parkos CA. Macrophage-dependent neutrophil recruitment is impaired under conditions of increased intestinal permeability in JAM-A-deficient mice. Mucosal Immunol 2019; 12:668-678. [PMID: 30745566 PMCID: PMC6543824 DOI: 10.1038/s41385-019-0143-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 01/15/2019] [Accepted: 01/16/2019] [Indexed: 02/07/2023]
Abstract
Junctional adhesion molecule-A (JAM-A) is a transmembrane glycoprotein expressed on leukocytes, endothelia, and epithelia that regulates biological processes including barrier function and immune responses. While JAM-A has been reported to facilitate tissue infiltration of leukocytes under inflammatory conditions, the contributions of leukocyte-expressed JAM-A in vivo remain unresolved. We investigated the role of leukocyte-expressed JAM-A in acute peritonitis induced by zymosan, lipopolysaccharide (LPS), or TNFα using mice with selective loss of JAM-A in myelomonocytic cells (LysM-Cre;Jam-afl/fl). Surprisingly, in LysM-Cre;Jam-afl/fl mice, loss of JAM-A did not affect neutrophil (PMN) recruitment into the peritoneum in response to zymosan, LPS, or TNFα although it was significantly reduced in Jam-aKO mice. In parallel, Jam-aKO peritoneal macrophages exhibited diminished CXCL1 chemokine production and decreased activation of NF-kB, whereas those from LysM-Cre;Jam-afl/fl mice were unaffected. Using Villin-Cre;Jam-afl/fl mice, targeted loss of JAM-A on intestinal epithelial cells resulted in increased intestinal permeability along with reduced peritoneal PMN migration as well as lower levels of CXCL1 and active NF-kB similar to that observed in Jam-aKO animals. Interestingly, in germ-free Villin-Cre;Jam-afl/fl mice, PMN recruitment was unaffected suggesting dependence on gut microbiota. Such observations highlight the functional link between a leaky gut and regulation of innate immune responses.
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Affiliation(s)
| | - Holly C Williams
- Department of Medicine, Division of Cardiology, Emory University, Atlanta, GA, USA
| | - Wooki Kim
- Department of Food Science and Biotechnology, Kyung Hee University, Yongin, Korea
| | - Sven Flemming
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | - Veronica Azcutia
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | | | | | - Timothy L Denning
- Center for Inflammation, Immunity and Infection, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, USA
| | - Asma Nusrat
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | - Charles A Parkos
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA.
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10
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Fan S, Weight CM, Luissint AC, Hilgarth RS, Brazil JC, Ettel M, Nusrat A, Parkos CA. Role of JAM-A tyrosine phosphorylation in epithelial barrier dysfunction during intestinal inflammation. Mol Biol Cell 2019; 30:566-578. [PMID: 30625033 PMCID: PMC6589701 DOI: 10.1091/mbc.e18-08-0531] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Junctional adhesion molecule-A (JAM-A), an epithelial tight junction protein, plays an important role in regulating intestinal permeability through association with a scaffold signaling complex containing ZO-2, Afadin, and the small GTPase Rap2. Under inflammatory conditions, we report that the cytoplasmic tail of JAM-A is tyrosine phosphorylated (p-Y280) in association with loss of barrier function. While barely detectable Y280 phosphorylation was observed in confluent monolayers of human intestinal epithelial cells under basal conditions, exposure to cytokines TNFα, IFNγ, IL-22, or IL-17A, resulted in compromised barrier function in parallel with increased p-Y280. Phosphorylation was Src kinase dependent, and we identified Yes-1 and PTPN13 as a major kinase and phosphatase for p-JAM-A Y280, respectively. Moreover, cytokines IL-22 or IL-17A induced increased activity of Yes-1. Furthermore, the Src kinase inhibitor PP2 rescued cytokine-induced epithelial barrier defects and inhibited phosphorylation of JAM-A Y280 in vitro. Phosphorylation of JAM-A Y280 and increased permeability correlated with reduced JAM-A association with active Rap2. Finally, we observed increased phosphorylation of Y280 in colonic epithelium of individuals with ulcerative colitis and in mice with experimentally induced colitis. These findings support a novel mechanism by which tyrosine phosphorylation of JAM-A Y280 regulates epithelial barrier function during inflammation.
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Affiliation(s)
- Shuling Fan
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | - Caroline M Weight
- Division of Infection and Immunity, University College London, London WC1E 6BT, United Kingdom
| | | | - Roland S Hilgarth
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | - Jennifer C Brazil
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | - Mark Ettel
- Department of Pathology, University of Rochester Medical Center, Rochester, NY 14642
| | - Asma Nusrat
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
| | - Charles A Parkos
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
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11
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Flemming S, Luissint AC, Nusrat A, Parkos CA. Analysis of leukocyte transepithelial migration using an in vivo murine colonic loop model. JCI Insight 2018; 3:99722. [PMID: 30333307 DOI: 10.1172/jci.insight.99722] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 09/11/2018] [Indexed: 12/30/2022] Open
Abstract
Molecular mechanisms that control leukocyte migration across the vascular endothelium (transendothelial migration; TEndoM) have been extensively characterized in vivo, but details of leukocyte transepithelial migration (TEpM) and its dysregulation (a pathologic feature of many mucosal diseases) are missing due to the lack of suitable animal models. Here, we describe a murine model that utilizes a vascularized proximal colonic segment (pcLoop) and enables quantitative studies of leukocyte trafficking across colonic epithelium. Consistent with previous in vitro studies, intraluminal injection of antibodies against integrin CD11b/CD18 reduced recruitment of polymorphonuclear neutrophils (PMN) into the lumen of pcLoops, and it increased subepithelial accumulation of PMN. We extended studies using the pcLoop to determine contributions of Junctional Adhesion Molecule-A (JAM-A, or F11R) in PMN TEpM and confirmed that mice with total loss of JAM-A or mice with intestinal epithelial selective loss of JAM-A had increased colonic permeability. Furthermore, there was reduced PMN migration into the colonic lumen that paralleled subepithelial accumulation of PMN in global-KO mice, as well as in intestinal epithelial-targeted JAM-A-deficient mice. These findings highlight a potentially novel role for JAM-A in regulating PMN TEpM in vivo and demonstrate utility of this model for identifying receptors that may be targeted in vivo to reduce pathologic intestinal inflammation.
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Luissint AC, Parkos CA, Nusrat A. Inflammation and the Intestinal Barrier: Leukocyte-Epithelial Cell Interactions, Cell Junction Remodeling, and Mucosal Repair. Gastroenterology 2016; 151:616-32. [PMID: 27436072 PMCID: PMC5317033 DOI: 10.1053/j.gastro.2016.07.008] [Citation(s) in RCA: 323] [Impact Index Per Article: 40.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 06/13/2016] [Accepted: 07/06/2016] [Indexed: 02/06/2023]
Abstract
The intestinal tract is lined by a single layer of columnar epithelial cells that forms a dynamic, permeable barrier allowing for selective absorption of nutrients, while restricting access to pathogens and food-borne antigens. Precise regulation of epithelial barrier function is therefore required for maintaining mucosal homeostasis and depends, in part, on barrier-forming elements within the epithelium and a balance between pro- and anti-inflammatory factors in the mucosa. Pathologic states, such as inflammatory bowel disease, are associated with a leaky epithelial barrier, resulting in excessive exposure to microbial antigens, recruitment of leukocytes, release of soluble mediators, and ultimately mucosal damage. An inflammatory microenvironment affects epithelial barrier properties and mucosal homeostasis by altering the structure and function of epithelial intercellular junctions through direct and indirect mechanisms. We review our current understanding of complex interactions between the intestinal epithelium and immune cells, with a focus on pathologic mucosal inflammation and mechanisms of epithelial repair. We discuss leukocyte-epithelial interactions, as well as inflammatory mediators that affect the epithelial barrier and mucosal repair. Increased knowledge of communication networks between the epithelium and immune system will lead to tissue-specific strategies for treating pathologic intestinal inflammation.
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Affiliation(s)
| | | | - Asma Nusrat
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan.
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Monteiro AC, Luissint AC, Sumagin R, Lai C, Vielmuth F, Wolf MF, Laur O, Reiss K, Spindler V, Stehle T, Dermody TS, Nusrat A, Parkos CA. Trans-dimerization of JAM-A regulates Rap2 and is mediated by a domain that is distinct from the cis-dimerization interface. Mol Biol Cell 2014; 25:1574-85. [PMID: 24672055 PMCID: PMC4019489 DOI: 10.1091/mbc.e14-01-0018] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Junctional adhesion molecule-A (JAM-A) is a tight junction–associated signaling protein that homodimerizes across cells at a unique motif to activate the small GTPase Rap2, previously implicated in the regulation of barrier function. JAM-A may therefore act as a barrier-inducing molecular switch that is activated when cells become confluent. Junctional adhesion molecule-A (JAM-A) is a tight junction–associated signaling protein that regulates epithelial cell proliferation, migration, and barrier function. JAM-A dimerization on a common cell surface (in cis) has been shown to regulate cell migration, and evidence suggests that JAM-A may form homodimers between cells (in trans). Indeed, transfection experiments revealed accumulation of JAM-A at sites between transfected cells, which was lost in cells expressing cis- or predicted trans-dimerization null mutants. Of importance, microspheres coated with JAM-A containing alanine substitutions to residues 43NNP45 (NNP-JAM-A) within the predicted trans-dimerization site did not aggregate. In contrast, beads coated with cis-null JAM-A demonstrated enhanced clustering similar to that observed with wild-type (WT) JAM-A. In addition, atomic force microscopy revealed decreased association forces in NNP-JAM-A compared with WT and cis-null JAM-A. Assessment of effects of JAM-A dimerization on cell signaling revealed that expression of trans- but not cis-null JAM-A mutants decreased Rap2 activity. Furthermore, confluent cells, which enable trans-dimerization, had enhanced Rap2 activity. Taken together, these results suggest that trans-dimerization of JAM-A occurs at a unique site and with different affinity compared with dimerization in cis. Trans-dimerization of JAM-A may thus act as a barrier-inducing molecular switch that is activated when cells become confluent.
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Affiliation(s)
- Ana C Monteiro
- Epithelial Pathobiology and Mucosal Inflammation Research Unit, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322
| | - Anny-Claude Luissint
- Epithelial Pathobiology and Mucosal Inflammation Research Unit, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322
| | - Ronen Sumagin
- Epithelial Pathobiology and Mucosal Inflammation Research Unit, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322
| | - Caroline Lai
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232Elizabeth B. Lamb Center for Pediatric Research, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Franziska Vielmuth
- Institute of Anatomy and Cell Biology, Ludwig-Maximilians University, 80336 Munich, Germany
| | - Mattie F Wolf
- Epithelial Pathobiology and Mucosal Inflammation Research Unit, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322
| | - Oskar Laur
- Epithelial Pathobiology and Mucosal Inflammation Research Unit, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322
| | - Kerstin Reiss
- Interfaculty Institute of Biochemistry, University of Tübingen, D-72076 Tübingen, Germany
| | - Volker Spindler
- Institute of Anatomy and Cell Biology, Ludwig-Maximilians University, 80336 Munich, Germany
| | - Thilo Stehle
- Elizabeth B. Lamb Center for Pediatric Research, Vanderbilt University School of Medicine, Nashville, TN 37232Interfaculty Institute of Biochemistry, University of Tübingen, D-72076 Tübingen, Germany
| | - Terence S Dermody
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232Elizabeth B. Lamb Center for Pediatric Research, Vanderbilt University School of Medicine, Nashville, TN 37232Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Asma Nusrat
- Epithelial Pathobiology and Mucosal Inflammation Research Unit, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322
| | - Charles A Parkos
- Epithelial Pathobiology and Mucosal Inflammation Research Unit, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322
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Luissint AC, Nusrat A, Parkos CA. JAM-related proteins in mucosal homeostasis and inflammation. Semin Immunopathol 2014; 36:211-26. [PMID: 24667924 DOI: 10.1007/s00281-014-0421-0] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 02/25/2014] [Indexed: 02/06/2023]
Abstract
Mucosal surfaces are lined by epithelial cells that form a physical barrier protecting the body against external noxious substances and pathogens. At a molecular level, the mucosal barrier is regulated by tight junctions (TJs) that seal the paracellular space between adjacent epithelial cells. Transmembrane proteins within TJs include junctional adhesion molecules (JAMs) that belong to the cortical thymocyte marker for Xenopus family of proteins. JAM family encompasses three classical members (JAM-A, JAM-B, and JAM-C) and related molecules including JAM4, JAM-like protein, Coxsackie and adenovirus receptor (CAR), CAR-like membrane protein and endothelial cell-selective adhesion molecule. JAMs have multiple functions that include regulation of endothelial and epithelial paracellular permeability, leukocyte recruitment during inflammation, angiogenesis, cell migration, and proliferation. In this review, we summarize the current knowledge regarding the roles of the JAM family members in the regulation of mucosal homeostasis and leukocyte trafficking with a particular emphasis on barrier function and its perturbation during pathological inflammation.
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Affiliation(s)
- Anny-Claude Luissint
- Epithelial pathobiology and mucosal inflammation research unit, Department of Pathology and Laboratory Medicine, Emory University, 615 Michael Street, 30306, Atlanta, GA, USA
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Molina A, Velot L, Ghouinem L, Abdelkarim M, Bouchet BP, Luissint AC, Bouhlel I, Morel M, Sapharikas E, Di Tommaso A, Honoré S, Braguer D, Gruel N, Vincent-Salomon A, Delattre O, Sigal-Zafrani B, André F, Terris B, Akhmanova A, Di Benedetto M, Nahmias C, Rodrigues-Ferreira S. ATIP3, a novel prognostic marker of breast cancer patient survival, limits cancer cell migration and slows metastatic progression by regulating microtubule dynamics. Cancer Res 2013; 73:2905-15. [PMID: 23396587 DOI: 10.1158/0008-5472.can-12-3565] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Metastasis, a fatal complication of breast cancer, does not fully benefit from available therapies. In this study, we investigated whether ATIP3, the major product of 8p22 MTUS1 gene, may be a novel biomarker and therapeutic target for metastatic breast tumors. We show that ATIP3 is a prognostic marker for overall survival among patients with breast cancer. Notably, among metastatic tumors, low ATIP3 levels associate with decreased survival of the patients. By using a well-defined experimental mouse model of cancer metastasis, we show that ATIP3 expression delays the time-course of metastatic progression and limits the number and size of metastases in vivo. In functional studies, ATIP3 silencing increases breast cancer cell migration, whereas ATIP3 expression significantly reduces cell motility and directionality. We report here that ATIP3 is a potent microtubule-stabilizing protein whose depletion increases microtubule dynamics. Our data support the notion that by decreasing microtubule dynamics, ATIP3 controls the ability of microtubule tips to reach the cell cortex during migration, a mechanism that may account for reduced cancer cell motility and metastasis. Of interest, we identify a functional ATIP3 domain that associates with microtubules and recapitulates the effects of ATIP3 on microtubule dynamics, cell proliferation, and migration. Our study is a major step toward the development of new personalized treatments against metastatic breast tumors that have lost ATIP3 expression.
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Affiliation(s)
- Angie Molina
- Institut National de la Santé et de la Recherche Medicale (Inserm), U1016, Institut Cochin, France
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Luissint AC, Artus C, Glacial F, Ganeshamoorthy K, Couraud PO. Tight junctions at the blood brain barrier: physiological architecture and disease-associated dysregulation. Fluids Barriers CNS 2012; 9:23. [PMID: 23140302 PMCID: PMC3542074 DOI: 10.1186/2045-8118-9-23] [Citation(s) in RCA: 388] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 10/21/2012] [Indexed: 01/01/2023] Open
Abstract
The Blood–brain barrier (BBB), present at the level of the endothelium of cerebral blood vessels, selectively restricts the blood-to-brain paracellular diffusion of compounds; it is mandatory for cerebral homeostasis and proper neuronal function. The barrier properties of these specialized endothelial cells notably depend on tight junctions (TJs) between adjacent cells: TJs are dynamic structures consisting of a number of transmembrane and membrane-associated cytoplasmic proteins, which are assembled in a multimolecular complex and acting as a platform for intracellular signaling. Although the structural composition of these complexes has been well described in the recent years, our knowledge about their functional regulation still remains fragmentary. Importantly, pericytes, embedded in the vascular basement membrane, and perivascular microglial cells, astrocytes and neurons contribute to the regulation of endothelial TJs and BBB function, altogether constituting the so-called neurovascular unit. The present review summarizes our current understanding of the structure and functional regulation of endothelial TJs at the BBB. Accumulating evidence points to a correlation between BBB dysfunction, alteration of TJ complexes and progression of a variety of CNS diseases, such as stroke, multiple sclerosis and brain tumors, as well as neurodegenerative diseases like Parkinson’s and Alzheimer’s diseases. Understanding how TJ integrity is controlled may thus help improve drug delivery across the BBB and the design of therapeutic strategies for neurological disorders.
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Luissint AC, Federici C, Guillonneau F, Chrétien F, Camoin L, Glacial F, Ganeshamoorthy K, Couraud PO. Guanine nucleotide-binding protein Gαi2: a new partner of claudin-5 that regulates tight junction integrity in human brain endothelial cells. J Cereb Blood Flow Metab 2012; 32:860-73. [PMID: 22333621 PMCID: PMC3345908 DOI: 10.1038/jcbfm.2011.202] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The blood-brain barrier (BBB) selectively controls the exchanges between the blood and the brain: it is formed by tight junctions (TJs) between adjacent microvascular endothelial cells. The transmembrane protein claudin-5 is known as a key TJ protein at the BBB, although, the molecular mechanisms by which it regulates TJ tightness are poorly understood. To identify putative claudin-5 partners that contribute to TJ integrity, claudin-5-enriched membrane microdomains were prepared by cell fractionation, using the human brain endothelial cell line hCMEC/D3 and claudin-5 immunoprecipitates were submitted to tandem mass spectrometry. Because a high concentration of mannitol is known to transiently destabilize TJs, this analysis was performed in basal conditions, after mannitol treatment, and after recovery of TJ integrity. We here demonstrate that the G-protein subunit αi2 (Gαi2) interacts with claudin-5 and that association is correlated with TJ integrity in hCMEC/D3 cells; also, a selective expression of Gαi2 is observed in human brain vasculature in situ. Moreover, small interfering RNA-mediated depletion of Gαi2 or claudin-5 in hCMEC/D3 cells similarly increases their paracellular permeability and delays TJ recovery after mannitol treatment. Altogether, our results identify Gαi2 as a novel claudin-5 partner required for TJ integrity in brain endothelial cells.
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Luissint AC, Lutz PG, Calderwood DA, Couraud PO, Bourdoulous S. JAM-L-mediated leukocyte adhesion to endothelial cells is regulated in cis by α4β1 integrin activation. J Gen Physiol 2009. [DOI: 10.1085/jgp1331oia1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Luissint AC, Lutz PG, Calderwood DA, Couraud PO, Bourdoulous S. JAM-L–mediated leukocyte adhesion to endothelial cells is regulated in cis by a4b1 integrin activation. J Exp Med 2008. [DOI: 10.1084/jem20513oia29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Luissint AC, Lutz PG, Calderwood DA, Couraud PO, Bourdoulous S. JAM-L-mediated leukocyte adhesion to endothelial cells is regulated in cis by alpha4beta1 integrin activation. ACTA ACUST UNITED AC 2008; 183:1159-73. [PMID: 19064666 PMCID: PMC2600739 DOI: 10.1083/jcb.200805061] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Junctional adhesion molecules (JAMs) are endothelial and epithelial adhesion molecules involved in the recruitment of circulating leukocytes to inflammatory sites. We show here that JAM-L, a protein related to the JAM family, is restricted to leukocytes and promotes their adhesion to endothelial cells. Cis dimerization of JAM-L is required to engage in heterophilic interactions with its cognate counter-receptor CAR (coxsackie and adenovirus receptor). Interestingly, JAM-L expressed on neutrophils binds CAR independently of integrin activation. However, on resting monocytes and T lymphocytes, which express the integrin VLA-4, JAM-L molecules engage in complexes with VLA-4 and mainly accumulate in their monomeric form. Integrin activation is required for the dissociation of JAM-L–VLA-4 complexes and the accumulation of functional JAM-L dimers, which indicates that the leukocyte integrin VLA-4 controls JAM-L function in cis by controlling its dimerization state. This provides a mechanism through which VLA-4 and JAM-L functions are coordinately regulated, allowing JAM-L to strengthen integrin-dependent adhesion of leukocytes to endothelial cells.
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Affiliation(s)
- Anny-Claude Luissint
- Institut Cochin, Université Paris Descartes, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8104, Paris F-75014, France
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