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Into the Tissues: Extracellular Matrix and Its Artificial Substitutes: Cell Signalling Mechanisms. Cells 2022; 11:cells11050914. [PMID: 35269536 PMCID: PMC8909573 DOI: 10.3390/cells11050914] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/02/2022] [Accepted: 03/04/2022] [Indexed: 02/06/2023] Open
Abstract
The existence of orderly structures, such as tissues and organs is made possible by cell adhesion, i.e., the process by which cells attach to neighbouring cells and a supporting substance in the form of the extracellular matrix. The extracellular matrix is a three-dimensional structure composed of collagens, elastin, and various proteoglycans and glycoproteins. It is a storehouse for multiple signalling factors. Cells are informed of their correct connection to the matrix via receptors. Tissue disruption often prevents the natural reconstitution of the matrix. The use of appropriate implants is then required. This review is a compilation of crucial information on the structural and functional features of the extracellular matrix and the complex mechanisms of cell–cell connectivity. The possibilities of regenerating damaged tissues using an artificial matrix substitute are described, detailing the host response to the implant. An important issue is the surface properties of such an implant and the possibilities of their modification.
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Carthew J, Taylor JBJ, Garcia-Cruz MR, Kiaie N, Voelcker NH, Cadarso VJ, Frith JE. The Bumpy Road to Stem Cell Therapies: Rational Design of Surface Topographies to Dictate Stem Cell Mechanotransduction and Fate. ACS APPLIED MATERIALS & INTERFACES 2022; 14:23066-23101. [PMID: 35192344 DOI: 10.1021/acsami.1c22109] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Cells sense and respond to a variety of physical cues from their surrounding microenvironment, and these are interpreted through mechanotransductive processes to inform their behavior. These mechanisms have particular relevance to stem cells, where control of stem cell proliferation, potency, and differentiation is key to their successful application in regenerative medicine. It is increasingly recognized that surface micro- and nanotopographies influence stem cell behavior and may represent a powerful tool with which to direct the morphology and fate of stem cells. Current progress toward this goal has been driven by combined advances in fabrication technologies and cell biology. Here, the capacity to generate precisely defined micro- and nanoscale topographies has facilitated the studies that provide knowledge of the mechanotransducive processes that govern the cellular response as well as knowledge of the specific features that can drive cells toward a defined differentiation outcome. However, the path forward is not fully defined, and the "bumpy road" that lays ahead must be crossed before the full potential of these approaches can be fully exploited. This review focuses on the challenges and opportunities in applying micro- and nanotopographies to dictate stem cell fate for regenerative medicine. Here, key techniques used to produce topographic features are reviewed, such as photolithography, block copolymer lithography, electron beam lithography, nanoimprint lithography, soft lithography, scanning probe lithography, colloidal lithography, electrospinning, and surface roughening, alongside their advantages and disadvantages. The biological impacts of surface topographies are then discussed, including the current understanding of the mechanotransductive mechanisms by which these cues are interpreted by the cells, as well as the specific effects of surface topographies on cell differentiation and fate. Finally, considerations in translating these technologies and their future prospects are evaluated.
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Affiliation(s)
- James Carthew
- Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
| | - Jason B J Taylor
- Mechanical and Aerospace Engineering, Monash University, Clayton, Victoria 3800, Australia
| | - Maria R Garcia-Cruz
- Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
| | - Nasim Kiaie
- Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
| | - Nicolas H Voelcker
- Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication Facility, Clayton, Victoria 3168, Australia
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
- ARC Centre for Cell and Tissue Engineering Technologies, Monash University, Clayton, Victoria 3800, Australia
- CSIRO Manufacturing, Bayview Avenue, Clayton, VIC 3168, Australia
| | - Victor J Cadarso
- Mechanical and Aerospace Engineering, Monash University, Clayton, Victoria 3800, Australia
- Centre to Impact Antimicrobial Resistance, Monash University, Clayton, Victoria 3800, Australia
| | - Jessica E Frith
- Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
- ARC Centre for Cell and Tissue Engineering Technologies, Monash University, Clayton, Victoria 3800, Australia
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria 3800, Australia
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Allen J, Ryu J, Maggi A, Flores B, Greer JR, Desai T. Tunable Microfibers Suppress Fibrotic Encapsulation via Inhibition of TGFβ Signaling. Tissue Eng Part A 2015; 22:142-50. [PMID: 26507808 DOI: 10.1089/ten.tea.2015.0087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Fibrotic encapsulation limits the efficacy and lifetime of implantable biomedical devices. Microtopography has shown promise in the regulation of myofibroblast differentiation, a key driver of fibrotic encapsulation. However, existing studies have not systematically isolated the requisite geometric parameters for suppression of myofibroblast differentiation via microtopography, and there has not been in vivo validation of this technology to date. To address these issues, a novel lamination method was developed to afford more control over topography dimensions. Specifically, in this study we focus on fiber length and its effect on myofibroblast differentiation. Fibroblasts cultured on films with microfibers exceeding 16 μm in length lost the characteristic morphology associated with myofibroblast differentiation, while shorter microfibers of 6 μm length failed to produce this phenotype. This increase in length corresponded to a 50% decrease in fiber stiffness, which acts as a mechanical cue to influence myofibroblast differentiation. Longer microfiber films suppressed expression of myofibroblast-specific genes (αSMA, Col1α2, and Col3α1) and TGFβ signaling components (TGFβ1, TβR2, and Smad3). About 16 μm long microfiber films subcutaneously implanted in a mouse wound-healing model generated a substantially thinner fibrotic capsule and less deposition of collagen in the wound bed. Together, these results identify a critical feature length threshold for microscale topography-mediated repression of fibrotic encapsulation. This study also demonstrates a simple and powerful strategy to improve surface biocompatibility and reduce fibrotic encapsulation around implanted materials.
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Affiliation(s)
- Jessica Allen
- 1 UCSF Department of Bioengineering and Therapeutic Sciences, San Francisco , California
| | - Jubin Ryu
- 2 UCSF Department of Dermatology, San Francisco , California
| | - Alessandro Maggi
- 3 California Institute of Technology , Department of Medical Engineering, Pasadena, California
| | - Bianca Flores
- 1 UCSF Department of Bioengineering and Therapeutic Sciences, San Francisco , California
| | - Julia R Greer
- 4 California Institute of Technology, Division of Engineering and Applied Science, Kavli Nanoscience Institute , Pasadena, California
| | - Tejal Desai
- 1 UCSF Department of Bioengineering and Therapeutic Sciences, San Francisco , California
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4
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Pinney JR, Du KT, Ayala P, Fang Q, Sievers RE, Chew P, Delrosario L, Lee RJ, Desai TA. Discrete microstructural cues for the attenuation of fibrosis following myocardial infarction. Biomaterials 2014; 35:8820-8828. [PMID: 25047625 DOI: 10.1016/j.biomaterials.2014.07.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 07/02/2014] [Indexed: 01/14/2023]
Abstract
Chronic fibrosis caused by acute myocardial infarction (MI) leads to increased morbidity and mortality due to cardiac dysfunction. We have developed a therapeutic materials strategy that aims to mitigate myocardial fibrosis by utilizing injectable polymeric microstructures to mechanically alter the microenvironment. Polymeric microstructures were fabricated using photolithographic techniques and studied in a three-dimensional culture model of the fibrotic environment and by direct injection into the infarct zone of adult rats. Here, we show dose-dependent down-regulation of expression of genes associated with the mechanical fibrotic response in the presence of microstructures. Injection of this microstructured material into the infarct zone decreased levels of collagen and TGF-β, increased elastin deposition and vascularization in the infarcted region, and improved functional outcomes after six weeks. Our results demonstrate the efficacy of these discrete anti-fibrotic microstructures and suggest a potential therapeutic materials approach for combatting pathologic fibrosis.
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Affiliation(s)
- James R Pinney
- UC Berkeley - UCSF Graduate Group in Bioengineering, 1700 4th Street, QB3 Byers Hall, Room 203, San Francisco, CA 94158, USA; UCSF Medical Scientist Training Program, 1700 4th Street, QB3 Byers Hall, Room 203, San Francisco, CA 94158, USA
| | - Kim T Du
- UCSF Department of Medicine, Cardiovascular Research Institute and Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Box 1354, 513 Parnassus Ave, MS Room 1136, San Francisco, CA 94143, USA
| | - Perla Ayala
- UC Berkeley - UCSF Graduate Group in Bioengineering, 1700 4th Street, QB3 Byers Hall, Room 203, San Francisco, CA 94158, USA; Beth Israel Deaconess Medical Center, Department of Surgery, Center for Life Science Surgery/BIDMC, 11th Floor, 3 Blackfan Circle, Boston, MA 02115, USA
| | - Qizhi Fang
- UCSF Department of Medicine, Cardiovascular Research Institute and Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Box 1354, 513 Parnassus Ave, MS Room 1136, San Francisco, CA 94143, USA
| | - Richard E Sievers
- UCSF Department of Medicine, Cardiovascular Research Institute and Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Box 1354, 513 Parnassus Ave, MS Room 1136, San Francisco, CA 94143, USA
| | - Patrick Chew
- UCSF Bioengineering and Therapeutic Sciences, 1700 4th Street, Byers Hall Room 203, San Francisco, CA 94158, USA
| | - Lawrence Delrosario
- UCSF School of Medicine, 513 Parnassus Ave, MS Room 1136, San Francisco, CA 94143, USA
| | - Randall J Lee
- UC Berkeley - UCSF Graduate Group in Bioengineering, 1700 4th Street, QB3 Byers Hall, Room 203, San Francisco, CA 94158, USA; UCSF Department of Medicine, Cardiovascular Research Institute and Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Box 1354, 513 Parnassus Ave, MS Room 1136, San Francisco, CA 94143, USA
| | - Tejal A Desai
- UC Berkeley - UCSF Graduate Group in Bioengineering, 1700 4th Street, QB3 Byers Hall, Room 203, San Francisco, CA 94158, USA; UCSF Bioengineering and Therapeutic Sciences, 1700 4th Street, Byers Hall Room 203, San Francisco, CA 94158, USA.
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Magin CM, Alge DL, Gould ST, Anseth KS. Clickable, photodegradable hydrogels to dynamically modulate valvular interstitial cell phenotype. Adv Healthc Mater 2014; 3:649-57. [PMID: 24459068 DOI: 10.1002/adhm.201300288] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 09/26/2013] [Indexed: 11/06/2022]
Abstract
Biophysical cues are widely recognized to influence cell phenotype. While this evidence was established using static substrates, there is growing interest in creating stimulus-responsive biomaterials that better recapitulate the dynamic extracellular matrix. Here, a clickable, photodegradable hydrogel substrate that allows the user to precisely control substrate elasticity and topography in situ is presented. The hydrogels are synthesized by reacting an 8-arm poly(ethylene glycol) alkyne with an azide-functionalized photodegradable crosslinker. The utility of this platform by exploiting its photoresponsive properties to modulate the phenotype of porcine aortic valvular interstitial cells (VICs) is demonstrated. First, VIC phenotype is monitored, in response to initial substratum modulus and static topographic cues. Higher modulus (E ≈ 15 kPa) substrates induce higher levels of activation (≈70% myofibroblasts) versus soft (E ≈ 3 kPa) substrates (≈20% myofibroblasts). Microtopographies that induce VIC alignment and elongation on low modulus substrates also stimulate activation. Finally, VIC phenotype is monitored in response to sequential in situ manipulations. The results illustrate that VIC activation on stiff surfaces (≈70% myofibroblasts) can be partially reversed by reducing surface modulus (≈30% myofibroblats) and subsequently re-activated by anisotropic topographies (≈60% myofibroblasts). Such dynamic substrates afford unique opportunities to decipher the complex role of matrix cues on the plasticity of VIC activation.
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Affiliation(s)
- Chelsea M. Magin
- Department of Chemical and Biological Engineering and the BioFrontiers Institute University of Colorado 596 UCB Boulder CO 80303舑0596 USA
| | - Daniel L. Alge
- Department of Chemical and Biological Engineering and the BioFrontiers Institute University of Colorado 596 UCB Boulder CO 80303舑0596 USA
- The Howard Hughes Medical Institute University of Colorado 596 UCB Boulder CO 80303舑1904 USA
| | - Sarah T. Gould
- Department of Chemical and Biological Engineering and the BioFrontiers Institute University of Colorado 596 UCB Boulder CO 80303舑0596 USA
| | - Kristi S. Anseth
- Department of Chemical and Biological Engineering and the BioFrontiers Institute University of Colorado 596 UCB Boulder CO 80303舑0596 USA
- The Howard Hughes Medical Institute University of Colorado 596 UCB Boulder CO 80303舑1904 USA
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Zhuang Z, Zhou R, Xu X, Tian T, Liu Y, Liu Y, Lian P, Wang J, Xu K. Clinical significance of integrin αvβ6 expression effects on gastric carcinoma invasiveness and progression via cancer-associated fibroblasts. Med Oncol 2013; 30:580. [PMID: 23673986 DOI: 10.1007/s12032-013-0580-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 04/11/2013] [Indexed: 12/14/2022]
Abstract
Over-expression of integrin αvβ6 and increased numbers of cancer-associated fibroblasts (CAFs) play an important role in the development and progression of cancers. The aim of this study is to investigate the expression level of integrin αvβ6 and CAF numbers, their correlation with clinicopathologic features and their role in the prognosis of human gastric cancers. The expression levels of integrin αvβ6 and α-SMA in CAFs were analyzed by immunohistochemistry. Their correlation with clinicopathologic features, the relationships and the survival time of patients were also analyzed. The integrin αvβ6 expression levels were analyzed mainly in gastric cancers. The α-SMA expression levels were analyzed mainly in gastric cancers and paraneoplastic tissues. Patients with positive integrin β6 and α-SMA expression have a significantly lower overall survival rate than those with negative integrin β6 and α-SMA expression (P < 0.05). A multivariate analysis using a log-rank test indicated that patients with positive integrin β6 and α-SMA expression and/or a diffuse type of gastric cancer had a significantly poorer overall survival rate than did those with negative integrin β6 expression (P < 0.05). Integrin β6 expression correlated significantly with CAF numbers and served as a valuable prognostic indicator for human gastric cancers.
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Affiliation(s)
- Zhuonan Zhuang
- Department of Hepatobiliary Surgery, Qilu Hospital, Shandong University, Jinan 250012, People's Republic of China
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Uskoković V, Batarni SS, Schweicher J, King A, Desai TA. Effect of calcium phosphate particle shape and size on their antibacterial and osteogenic activity in the delivery of antibiotics in vitro. ACS APPLIED MATERIALS & INTERFACES 2013; 5:2422-31. [PMID: 23484624 PMCID: PMC3647690 DOI: 10.1021/am4000694] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Powders composed of four morphologically different calcium phosphate particles were prepared by precipitation from aqueous solutions: flaky, brick-like, elongated orthogonal, and spherical. The particles were then loaded with either clindamycin phosphate as the antibiotic of choice or fluorescein, a model molecule used to assess the drug release properties. A comparison was carried out of the effect of such antibiotic-releasing materials on: sustained drug release profiles; Staphylococcus aureus growth inhibition; and osteogenic propensities in vitro. Raman spectroscopic analysis indicated the presence of various calcium phosphate phases, including monetite (flaky and elongated orthogonal particles), octacalcium phosphate (brick-shaped particles), and hydroxyapatite (spherical particles). Testing the antibiotic-loaded calcium phosphate powders for bacterial growth inhibition demonstrated satisfying antibacterial properties both in broths and on agar plates. All four calcium-phosphate-fluorescein powders exhibited sustained drug release over 21 days. The calcium phosphate sample with the highest specific surface area and the smallest, spherical particle size was the most effective in both drug loading and release, consequently having the highest antibacterial efficiency. Moreover, the highest cell viability, the largest gene expression upregulation of three different osteogenic markers--osteocalcin, osteopontin, and Runx2--as well as the least disrupted cell cytoskeleton and cell morphologies were also noticed for the calcium phosphate powder composed of the smallest, spherical nanosized particles. Still, all four powders exerted a viable effect on osteoblastic MC3T3-E1 cells in vitro, as evidenced by both morphological assessments on fluorescently stained cells and measurements of their mitochondrial activity. The obtained results suggest that the nanoscale particle size and the corresponding coarseness of the surface of particle conglomerates as the cell attachment points may present a favorable starting point for the development of calcium-phosphate-based osteogenic drug delivery devices.
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Affiliation(s)
- Vuk Uskoković
- Therapeutic Micro and Nanotechnology Laboratory, Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California 94158-2330, United States.
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8
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Curtis MW, Budyn E, Desai TA, Samarel AM, Russell B. Microdomain heterogeneity in 3D affects the mechanics of neonatal cardiac myocyte contraction. Biomech Model Mechanobiol 2013; 12:95-109. [PMID: 22407215 PMCID: PMC3407350 DOI: 10.1007/s10237-012-0384-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 02/23/2012] [Indexed: 01/26/2023]
Abstract
Cardiac muscle cells are known to adapt to their physical surroundings, optimizing intracellular organization and contractile function for a given culture environment. A previously developed in vitro model system has shown that the inclusion of discrete microscale domains (or microrods) in three dimensions (3D) can alter long-term growth responses of neonatal ventricular myocytes. The aim of this work was to understand how cellular contact with such a domain affects various mechanical changes involved in cardiac muscle cell remodeling. Myocytes were maintained in 3D gels over 5 days in the presence or absence of 100-μm-long microrods, and the effect of this local heterogeneity on cell behavior was analyzed via several imaging techniques. Microrod abutment resulted in approximately twofold increases in the maximum displacement of spontaneously beating myocytes, as based on confocal microscopy scans of the gel xy-plane or the myocyte long axis. In addition, microrods caused significant increases in the proportion of aligned myofibrils (≤20° deviation from long axis) in fixed myocytes. Microrod-related differences in axial contraction could be abrogated by long-term interruption of certain signals of the RhoA-/Rho-associated kinase (ROCK) or protein kinase C (PKC) pathway. Furthermore, microrod-induced increases in myocyte size and protein content were prevented by ROCK inhibition. In all, the data suggest that microdomain heterogeneity in 3D appears to promote the development of axially aligned contractile machinery in muscle cells, an observation that may have relevance to a number of cardiac tissue engineering interventions.
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Affiliation(s)
- Matthew W. Curtis
- Department of Physiology and Biophysics, University of Illinois at Chicago, 835 South Wolcott Avenue, Chicago, IL 60612, USA
| | - Elisa Budyn
- Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, IL, USA
| | - Tejal A. Desai
- Department of Physiology and Division of Bioengineering, University of California at San Francisco, San Francisco, CA, USA
| | - Allen M. Samarel
- The Cardiovascular Institute, Loyola University Medical Center, Maywood, IL, USA
| | - Brenda Russell
- Department of Physiology and Biophysics, University of Illinois at Chicago, 835 South Wolcott Avenue, Chicago, IL 60612, USA,
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Horst OV, Chavez MG, Jheon AH, Desai T, Klein OD. Stem cell and biomaterials research in dental tissue engineering and regeneration. Dent Clin North Am 2012; 56:495-520. [PMID: 22835534 PMCID: PMC3494412 DOI: 10.1016/j.cden.2012.05.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2023]
Abstract
This review summarizes approaches used in tissue engineering and regenerative medicine, with a focus on dental applications. Dental caries and periodontal disease are the most common diseases resulting in tissue loss. To replace or regenerate new tissues, various sources of stem cells have been identified such as somatic stem cells from teeth and peridontium. Advances in biomaterial sciences including microfabrication, self-assembled biomimetic peptides, and 3-dimensional printing hold great promise for whole-organ or partial tissue regeneration to replace teeth and periodontium.
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Affiliation(s)
- Orapin V. Horst
- Division of Endodontics, Department of Preventive and Restorative Dental Sciences, University of California, San Francisco, Box 0758, 521 Parnassus Avenue, Clinical Science Building 627, San Francisco, CA 94143-0758, USA
| | - Miquella G. Chavez
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, Box 2330, 1700 4th Street, San Francisco, CA 94158-2330, USA
- Department of Orofacial Sciences, University of California, San Francisco, Box 0442, 513 Parnassus Avenue, San Francisco, CA 94143-0442, USA
| | - Andrew H. Jheon
- Department of Orofacial Sciences, University of California, San Francisco, Box 0442, 513 Parnassus Avenue, San Francisco, CA 94143-0442, USA
| | - Tejal Desai
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, Box 2330, 1700 4th Street, San Francisco, CA 94158-2330, USA
- Department of Physiology, University of California, San Francisco, Byers Hall Room 203C, MC 2520, 1700 4th Street, San Francisco, CA 94158-2330, USA
| | - Ophir D. Klein
- Department of Orofacial Sciences, University of California, San Francisco, Box 0442, 513 Parnassus Avenue, San Francisco, CA 94143-0442, USA
- Department of Pediatrics, University of California, San Francisco, Box 0442, 513 Parnassus Avenue, San Francisco, CA 94143-0442, USA
- Corresponding author. Department of Orofacial Sciences, University of California, San Francisco, Box 0442, 513 Parnassus Avenue, San Francisco, CA 94143-0442.
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