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Kiefer A, Plattner E, Ruppel R, Weiss C, Zhou-Suckow Z, Mall M, Renner M, Müller H. DMBT1 is upregulated in cystic fibrosis, affects ciliary motility, and is reduced by acetylcysteine. Mol Cell Pediatr 2022; 9:4. [PMID: 35249163 PMCID: PMC8898207 DOI: 10.1186/s40348-022-00136-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 01/26/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cystic fibrosis (CF) is the most common genetic disorder in the Caucasian population. Despite remarkable improvements in morbidity and mortality during the last decades, the disease still limits survival and reduces quality of life of affected patients. Moreover, CF still represents substantial economic burden for healthcare systems. Inflammation and infection already start in early life and play important roles in pulmonary impairment. The aim of this study is to analyze the potential role of DMBT1, a protein with functions in inflammation, angiogenesis, and epithelial differentiation, in CF. RESULTS Immunohistochemically DMBT1 protein expression was upregulated in lung tissues of CF patients compared to healthy controls. Additionally, pulmonary expression of Dmbt1 was approximately 6-fold increased in an established transgenic mouse model of CF-like lung disease (ENaC tg) compared to wild-type mice as detected by qRT-PCR. Since acetylcysteine (ACC) has been shown to reduce inflammatory markers in the airways, its potential influence on DMBT1 expression was analyzed. A549 cells stably transfected with an expression plasmid encoding the largest (8kb) DMBT1 variant (DMBT1+ cells) or an empty vector control (DMBT1- cells) and incubated with ACC both showed significantly reduced DMBT1 concentrations in the culture medium (p = 0.0001). To further elucidate the function of DMBT1 in pulmonary airways, respiratory epithelial cells were examined by phase contrast microscopy. Addition of human recombinant DMBT1 resulted in altered cilia motility and irregular beat waves (p < 0.0001) suggesting a potential effect of DMBT1 on airway clearance. CONCLUSIONS DMBT1 is part of inflammatory processes in CF and may be used as a potential biomarker for CF lung disease and a potential tool to monitor CF progression. Furthermore, DMBT1 has a negative effect on ciliary motility thereby possibly compromising airway clearance. Application of ACC, leading to reduced DMBT1 concentrations, could be a potential therapeutic option for CF patients.
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Affiliation(s)
- Alexander Kiefer
- Department of Pediatrics, University Hospital Erlangen, University of Erlangen-Nürnberg, Loschgestr. 15, 91054, Erlangen, Germany.,Department of Pediatric Pneumology and Allergology, St. Hedwig's Hospital of the Order of St. John, University Children's Hospital Regensburg (KUNO), Steinmetzstr. 1-3, 93049, Regensburg, Germany
| | - Erika Plattner
- Department of Pediatrics, University Hospital Erlangen, University of Erlangen-Nürnberg, Loschgestr. 15, 91054, Erlangen, Germany
| | - Renate Ruppel
- Department of Pediatrics, University Hospital Erlangen, University of Erlangen-Nürnberg, Loschgestr. 15, 91054, Erlangen, Germany
| | - Christel Weiss
- Department of Medical Statistics and Biomathematics, University Hospital Mannheim, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - Zhe Zhou-Suckow
- Department of Translational Pulmonology, Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), University of Heidelberg, Im Neuenheimer Feld, 69120, Heidelberg, Germany
| | - Marcus Mall
- Department of Pediatric Pulmonology, Immunology and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Marcus Renner
- Institute of Pathology, University of Heidelberg, Im Neuenheimer Feld 224, 69120, Heidelberg, Germany
| | - Hanna Müller
- Department of Pediatrics, Neonatology and Pediatric Intensive Care, University of Marburg, Baldingerstraße, 35043, Marburg, Germany. .,Department of Pediatrics, Division of Neonatology and Pediatric Intensive Care, University Hospital Erlangen, University of Erlangen-Nürnberg, Loschgestr. 15, 91054, Erlangen, Germany.
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Diez S, Besendörfer M, Weyerer V, Hartmann A, Moosmann J, Weiss C, Renner M, Müller H. DMBT1 expression and neutrophil-to-lymphocyte ratio during necrotizing enterocolitis are influenced by impaired perfusion due to cardiac anomalies. Mol Cell Pediatr 2022; 9:1. [PMID: 34989914 PMCID: PMC8739415 DOI: 10.1186/s40348-021-00133-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 12/15/2021] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Deleted in malignant brain tumors 1 (DMBT1) is involved in innate immunity and epithelial differentiation. It has been proven to play a role in various states of inflammation or hypoxia of fetal gastrointestinal and pulmonary diseases. Discrimination of pathogenesis in necrotizing enterocolitis (NEC) based on cardiac status improves the understanding of NEC in different patient subgroups. We aimed at examining DMBT1 expressions regarding their association with cardiac status leading to impaired intestinal perfusion, intraoperative bacteria proof, and a fulminant course of NEC. METHODS Twenty-eight patients with NEC were treated surgically between 2010 and 2019 at our institution. DMBT1 expression was examined in intestinal sections using immunohistochemistry to detect DMBT1 protein. Associations of clinical parameters and DMBT1 expression were analyzed. RESULTS We examined DMBT1 levels in 10 patients without cardiac defects and 18 patients with persisting ductus arteriosus (PDA) and congenital heart defects (CHD). Compared to patients without cardiac malformations, DMBT1 levels tended to score higher in patients with PDA/CHD (p = 0.2113) and were negatively correlated with C-reactive protein in these infants (p = 0.0172; r = - 0.5533). The number of DMBT1-expressing macrophages was elevated in the PDA/CHD-subgroup (p = 0.0399). Ratios of neutrophils and monocytes to lymphocytes were significantly higher in infants with PDA/CHD (p = 0.0319 and 0.0493). DMBT1 expression was significantly associated with positive bacterial culture of intraoperative swabs (p = 0.0252) and DMBT1 expression of the serosa was associated with a fulminant course of NEC (p = 0.0239). CONCLUSIONS This study demonstrates that DMBT1 expression may be influenced by cardiac anomalies with an impaired intestinal perfusion in the neonatal intestine. NEC in PDA/CHD infants is associated with more DMBT1-positive macrophages and a significantly elevated neutrophil-to-lymphocyte ratio.
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Affiliation(s)
- Sonja Diez
- Pediatric Surgery, Department for General Surgery, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestraße 15, 91054, Erlangen, Germany.
| | - Manuel Besendörfer
- Pediatric Surgery, Department for General Surgery, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestraße 15, 91054, Erlangen, Germany
| | - Veronika Weyerer
- Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Krankenhausstraße 8-10, 91054, Erlangen, Germany
| | - Arndt Hartmann
- Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Krankenhausstraße 8-10, 91054, Erlangen, Germany
| | - Julia Moosmann
- Department of Pediatric Cardiology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestraße 15, 91054, Erlangen, Germany
| | - Christel Weiss
- Department of Medical Statistics & Biomathematics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, Haus 3, Ebene 4, 68167, Mannheim, Germany
| | - Marcus Renner
- Institute of Pathology, Heidelberg University, Im Neuenheimer Feld 224, 69120, Heidelberg, Germany
| | - Hanna Müller
- Division of Neonatology and Pediatric Intensive Care, Department of Pediatrics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Loschgestraße 15, 91054, Erlangen, Germany.,Neonatology and Pediatric Intensive Care, Department of Pediatrics, University of Marburg, Baldingerstraße, 35033, Marburg, Germany
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Müller H, Schmiedl A, Weiss C, Ai M, Jung S, Renner M. DMBT1 is upregulated in lung epithelial cells after hypoxia and changes surfactant ultrastructure. Pediatr Pulmonol 2020; 55:2964-2969. [PMID: 32770804 DOI: 10.1002/ppul.25018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/05/2020] [Indexed: 11/11/2022]
Abstract
BACKGROUND Hypoxia and asphyxia are known to induce surfactant inactivation in newborns. Deleted in Malignant Brain Tumors 1 (DMBT1) is an innate immunity protein with functions in epithelial differentiation and angiogenesis. It was detected in hyaline membranes of infants with respiratory distress syndrome. Human recombinant DMBT1 is able to increase the surface tension of exogenous surfactant preparations in a dose-dependent manner. METHODS Immunohistochemistry was performed on lung sections of infants who died due to pre-, peri- or postnatal hypoxia. The lung epithelial cell line A549 was stably transfected with a DMBT1 (DMBT1+ cells) expression plasmid or with an empty plasmid (DMBT1- cells). The cells were cultured in normoxic or hypoxic conditions, and then DMBT1 as well as HIF-1α RNA expression were analyzed by using real-time-polymerase chain reaction. Human recombinant DMBT1 was added to the modified porcine natural surfactant Curosurf to examine the effect of DMBT1 on surfactant ultrastructure with electron microscopy. RESULTS DMBT1 expression was upregulated in human lung tissue after fetal/peri-/postnatal hypoxia. In addition, in vitro experiments showed increased DMBT1 RNA expression in A549 cells after hypoxia. HIF-1α was upregulated in both DMBT1+ and DMBT1- cells in response to hypoxia. The addition of human recombinant DMBT1 to Curosurf caused an impaired surfactant ultrastructure. CONCLUSIONS DMBT1 is upregulated in response to hypoxia and there seems to be a link between hypoxia and surfactant inactivation.
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Affiliation(s)
- Hanna Müller
- Division of Neonatology and Pediatric Intensive Care, Department of Pediatrics, University Hospital Erlangen, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Andreas Schmiedl
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - Christel Weiss
- Department for Medical Statistics and Biomathematics, University Hospital Mannheim, Mannheim, Germany
| | - Maria Ai
- Division of Neonatology and Pediatric Intensive Care, Department of Pediatrics, University Hospital Erlangen, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Susan Jung
- Department of Pediatrics, University Hospital Erlangen, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Marcus Renner
- Institute of Pathology, University of Heidelberg, Heidelberg, Germany
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Müller H, Weiss C, Renner M, Felderhoff-Müser U, Mollenhauer J. DMBT1 promotes basal and meconium-induced nitric oxide production in human lung epithelial cells in vitro. Histochem Cell Biol 2016; 147:389-397. [DOI: 10.1007/s00418-016-1493-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2016] [Indexed: 10/21/2022]
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Ren S, Chen X, Jiang L, Zhu B, Jiang Q, Xi X. Deleted in malignant brain tumors 1 protein is a potential biomarker of acute respiratory distress syndrome induced by pneumonia. Biochem Biophys Res Commun 2016; 478:1344-9. [PMID: 27565730 DOI: 10.1016/j.bbrc.2016.08.125] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 08/22/2016] [Indexed: 11/25/2022]
Abstract
Acute respiratory distress syndrome (ARDS) is associated with high mortality and morbidity. Early diagnosis and risk stratification in patients with ARDS should improve prognosis. Unfortunately, no clinical biomarkers are available for use in early diagnosis. Quantitative proteomics is a powerful tool for biomarker discovery in cancer, autoimmune diseases, and ARDS. Here, we employed isobaric tags for relative and absolute quantitation (iTRAQ) technology to identify potential biomarkers for early ARDS diagnosis and predict the risk for increased disease severity induced by pneumonia. We collected the bronchoalveolar lavage fluid (BALF) and plasma from ARDS patients with differing degrees of ARDS severity. We identified 338 proteins dysregulated in ARDS through iTRAQ, 18 of which showed significant differences with at least 1.5-fold differential expression in patients with mild or severe ARDS. Differential plasma expression of pulmonary surfactant associated protein A, apolipoprotein A1, and deleted in malignant brain tumors 1 protein (DMBT1) was verified in plasma samples. Our results indicate that DMBT1 can potentially serve as a biomarker for early ARDS diagnosis and disease severity assessment.
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Affiliation(s)
- Shan Ren
- Intensive Care Unit, Fu Xing Hospital, Capital Medical University, 20A Fuxing Men Wai Avenue, Beijing 100038, People's Republic of China; Intensive Care Unit, Hebei General Hospital, 348 Heping Western Road, Shijiazhuang 050051, People's Republic of China.
| | - Xia Chen
- Intensive Care Unit, Fu Xing Hospital, Capital Medical University, 20A Fuxing Men Wai Avenue, Beijing 100038, People's Republic of China.
| | - Li Jiang
- Intensive Care Unit, Fu Xing Hospital, Capital Medical University, 20A Fuxing Men Wai Avenue, Beijing 100038, People's Republic of China.
| | - Bo Zhu
- Intensive Care Unit, Fu Xing Hospital, Capital Medical University, 20A Fuxing Men Wai Avenue, Beijing 100038, People's Republic of China.
| | - Qi Jiang
- Intensive Care Unit, Fu Xing Hospital, Capital Medical University, 20A Fuxing Men Wai Avenue, Beijing 100038, People's Republic of China.
| | - Xiuming Xi
- Intensive Care Unit, Fu Xing Hospital, Capital Medical University, 20A Fuxing Men Wai Avenue, Beijing 100038, People's Republic of China.
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Müller H, Renner M, Helmke BM, Mollenhauer J, Felderhoff-Müser U. Elevated DMBT1 levels in neonatal gastrointestinal diseases. Histochem Cell Biol 2015; 145:227-37. [DOI: 10.1007/s00418-015-1381-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2015] [Indexed: 01/01/2023]
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Deleted in malignant brain tumors 1 (DMBT1) elicits increased VEGF and decreased IL-6 production in type II lung epithelial cells. BMC Pulm Med 2015; 15:32. [PMID: 25885541 PMCID: PMC4426184 DOI: 10.1186/s12890-015-0027-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Accepted: 03/24/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Deleted in malignant brain tumors 1 (DMBT1) is an innate defence protein expressed in the lungs of preterm infants and adults. Recent studies showed that DMBT1 is important in angiogenesis and can bind to different growth factors including VEGF. We aimed at examining relationships between VEGF and IL-6 levels to DMBT1 expression in the lungs of preterm and term infants and in lung epithelial cells in vitro. METHODS We examined by ELISA VEGF levels in 120 tracheal aspirates of 57 preterm and term infants and tested for correlation with different perinatal factors as well as with DMBT1 levels. To examine the effect of DMBT1 on VEGF and IL-6 expression we compared type II lung epithelial A549 cells stably transfected with a DMBT1 expression plasmid (DMBT1+ cells) to A549 cells stably transfected with an empty expression plasmid (DMBT1- cells). The concentrations of VEGF and IL-6 were determined via ELISA in the supernatant of the unstimulated cells and after stimulation with LPS, TNFα and Phorbol-12-myristate-13-acetate (PMA). RESULTS The VEGF levels in the tracheal aspirates of preterm and term infants were significantly correlated with DMBT1 levels (p = 0.0032), the postnatal age (p = 0.0073) and the presence of neonatal infection/sepsis (p = 0.0002). Unstimulated DMBT1+ A549 cells showed significantly higher VEGF expression (p = 0.0017) than DMBT1- cells. Significantly elevated VEGF levels were also confirmed for DMBT1+ cells after stimulation with TNFα (p = 0.0008), LPS (p = 0.0232) and PMA (p = 0.0025). The IL-6 levels were comparable in DMBT1+ versus DMBT1- cells without stimulation (p = 0.6028), but they were significantly reduced in DMBT1+ cells after stimulation with TNFα (p = 0.0003), LPS (p = 0.0088) and PMA (p = 0.0039). CONCLUSIONS The data indicate that DMBT1 promotes VEGF and suppresses IL-6 production in alveolar tissues, which could point to DMBT1 having a possible role in the transition from inflammation to regeneration and being a potentially useful clinical marker.
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Martínez VG, Moestrup SK, Holmskov U, Mollenhauer J, Lozano F. The conserved scavenger receptor cysteine-rich superfamily in therapy and diagnosis. Pharmacol Rev 2011; 63:967-1000. [PMID: 21880988 DOI: 10.1124/pr.111.004523] [Citation(s) in RCA: 138] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The scavenger receptor cysteine-rich (SRCR) superfamily of soluble or membrane-bound protein receptors is characterized by the presence of one or several repeats of an ancient and highly conserved protein module, the SRCR domain. This superfamily (SRCR-SF) has been in constant and progressive expansion, now up to more than 30 members. The study of these members is attracting growing interest, which parallels that in innate immunity. No unifying function has been described to date for the SRCR domains, this being the result of the limited knowledge still available on the physiology of most members of the SRCR-SF, but also of the sequence versatility of the SRCR domains. Indeed, involvement of SRCR-SF members in quite different functions, such as pathogen recognition, modulation of the immune response, epithelial homeostasis, stem cell biology, and tumor development, have all been described. This has brought to us new information, unveiling the possibility that targeting or supplementing SRCR-SF proteins could result in diagnostic and/or therapeutic benefit for a number of physiologic and pathologic states. Recent research has provided structural and functional insight into these proteins, facilitating the development of means to modulate the activity of SRCR-SF members. Indeed, some of these approaches are already in use, paving the way for a more comprehensive use of SRCR-SF members in the clinic. The present review will illustrate some available evidence on the potential of well known and new members of the SRCR-SF in this regard.
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Affiliation(s)
- Vanesa Gabriela Martínez
- Center Esther Koplowitz, Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
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Lessons from the biophysics of interfaces: Lung surfactant and tear fluid. Prog Retin Eye Res 2011; 30:204-15. [DOI: 10.1016/j.preteyeres.2011.02.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Revised: 02/11/2011] [Accepted: 02/15/2011] [Indexed: 12/26/2022]
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Madsen J, Mollenhauer J, Holmskov U. Review: Gp-340/DMBT1 in mucosal innate immunity. Innate Immun 2010; 16:160-7. [PMID: 20418254 DOI: 10.1177/1753425910368447] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Deleted in Malignant Brain Tumour 1 (DMBT1) is a gene that encodes alternatively spliced proteins involved in mucosal innate immunity. It also encodes a glycoprotein with a molecular mass of 340 kDa, and is referred to as gp-340 (DMBT1(gp340)) and salivary agglutinin (DMBT1(SAG)). DMBT1(gp340) is secreted into broncho-alveolar surface lining fluid whereas DMBT(SAG) is present in the saliva. The two molecules were shown to be identical and both interact with and agglutinate several Gram-negative and Gram-positive bacteria including Streptococcus mutans, a bacterium responsible for caries in the oral cavity. DMBT1(gp340) interacts with surfactant proteins A and D (SP-D). DMBT1(gp340) and SP-D can individually and together interact and agglutinate influenza A virus. DMBT1(gp340) also binds to HIV-1 and facilitates transcytosis of the virus into epithelial cells. DMBT1 binds to a variety of other host proteins, including serum and secretory IgA, C1q, lactoferrin, MUC5B and trefoil factor 2 (TFF2), all molecules with involvement in innate immunity and/or wound-healing processes. Recent generation of Dmbt1-deficient mice has provided the research field of DMBT1 with a model that allows research to progress from in vitro studies to in vivo functional studies of the multifunctional proteins encoded by the DMBT1 gene.
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Affiliation(s)
- Jens Madsen
- University of Southampton, Southampton General Hospital, UK.
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Müller H, Renner M, Helmke BM, End C, Weiss C, Poeschl J, Mollenhauer J. Deleted in Malignant Brain Tumors 1 is up-regulated in bacterial endocarditis and binds to components of vegetations. J Thorac Cardiovasc Surg 2009; 138:725-32. [DOI: 10.1016/j.jtcvs.2009.05.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2009] [Revised: 04/19/2009] [Accepted: 05/20/2009] [Indexed: 12/17/2022]
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Brodland GW, Yang J, Sweny J. Cellular interfacial and surface tensions determined from aggregate compression tests using a finite element model. HFSP JOURNAL 2009; 3:273-81. [PMID: 20057960 DOI: 10.2976/1.3175812] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2009] [Accepted: 06/20/2009] [Indexed: 12/26/2022]
Abstract
Although previous studies suggested that the interfacial tension gamma(cc) acting along cell-cell boundaries and the effective viscosity mu of the cell cytoplasm could be measured by compressing a spherical aggregate of cells between parallel plates, the mechanical understanding necessary to extract this information from these tests-tests that have provided the surface tension sigma(cm) acting along cell-medium interfaces-has been lacking. These tensions can produce net forces at the subcellular level and give rise to cell motions and tissue reorganization, the rates of which are regulated by mu. Here, a three-dimensional (3D) cell-based finite element model provides insight into the mechanics of the compression test, where these same forces are at work, and leads to quantitative relationships from which the effective viscosity mu of the cell cytoplasm, the tension gamma(cc) that acts along internal cell-cell interfaces and the surface tension sigma(cp) along the cell-platen boundaries can be determined from force-time curves and aggregate profiles. Tests on 5-day embryonic chick mesencephalon, neural retina, liver, and heart aggregates show that all of these properties vary significantly with cell type, except gamma(cc), which is remarkably constant. These properties are crucial for understanding cell rearrangement and tissue self-organization in contexts that include embryogenesis, cancer metastases, and tissue engineering.
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