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Seet LF, Chu SWL, Teng X, Toh LZ, Wong TT. Assessment of progressive alterations in collagen organization in the postoperative conjunctiva by multiphoton microscopy. BIOMEDICAL OPTICS EXPRESS 2020; 11:6495-6515. [PMID: 33282504 PMCID: PMC7687938 DOI: 10.1364/boe.403555] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/14/2020] [Accepted: 09/15/2020] [Indexed: 06/12/2023]
Abstract
Glaucoma filtration surgery (GFS) commonly fails due to excessive fibrosis. As collagen structure aberrations is implicated in adverse fibrotic progression, this study aims to uncover collagen organization alterations during postoperative scarring. Via quantitative second harmonic generation/two photon excitation multiphoton imaging, we reveal the scar development and phenotype in the mouse model of conjunctival scarring. We also show that multiphoton imaging corroborated the collagen ultrastructure anomaly characteristic of the SPARC-/- mouse postoperative conjunctiva. These data improve our understanding of postoperative conjunctival scarring and further enhance the utility of this model for the development of anti-fibrotic therapeutics for GFS.
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Affiliation(s)
- Li-Fong Seet
- Ocular Therapeutics and Drug Delivery, Singapore Eye Research Institute, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Duke-NUS Medical School, Singapore
- Co-corresponding authors
| | - Stephanie W L Chu
- Ocular Therapeutics and Drug Delivery, Singapore Eye Research Institute, Singapore
| | | | - Li Zhen Toh
- Ocular Therapeutics and Drug Delivery, Singapore Eye Research Institute, Singapore
| | - Tina T Wong
- Ocular Therapeutics and Drug Delivery, Singapore Eye Research Institute, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Duke-NUS Medical School, Singapore
- Glaucoma Service, Singapore National Eye Centre, Singapore
- Co-corresponding authors
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2
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Mostaço-Guidolin LB, Osei ET, Ullah J, Hajimohammadi S, Fouadi M, Li X, Li V, Shaheen F, Yang CX, Chu F, Cole DJ, Brandsma CA, Heijink IH, Maksym GN, Walker D, Hackett TL. Defective Fibrillar Collagen Organization by Fibroblasts Contributes to Airway Remodeling in Asthma. Am J Respir Crit Care Med 2020; 200:431-443. [PMID: 30950644 DOI: 10.1164/rccm.201810-1855oc] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Rationale: Histologic stains have been used as the gold standard to visualize extracellular matrix (ECM) changes associated with airway remodeling in asthma, yet they provide no information on the biochemical and structural characteristics of the ECM, which are vital to understanding alterations in tissue function.Objectives: To demonstrate the use of nonlinear optical microscopy (NLOM) and texture analysis algorithms to image fibrillar collagen (second harmonic generation) and elastin (two-photon excited autofluorescence), to obtain biochemical and structural information on the remodeled ECM environment in asthma.Methods: Nontransplantable donor lungs from donors with asthma (n = 13) and control (n = 12) donors were used for the assessment of airway collagen and elastin fibers by NLOM, and extraction of lung fibroblasts for in vitro experiments.Measurements and Main Results: Fibrillar collagen is not only increased but also highly disorganized and fragmented within large and small asthmatic airways compared with control subjects, using NLOM imaging. Furthermore, such structural alterations are present in pediatric and adult donors with asthma, irrespective of fatal disease. In vitro studies demonstrated that asthmatic airway fibroblasts are deficient in their packaging of fibrillar collagen-I and express less decorin, important for collagen fibril packaging. Packaging of collagen fibrils was found to be more disorganized in asthmatic airways compared with control subjects, using transmission electron microscopy.Conclusions: NLOM imaging enabled the structural assessment of the ECM, and the data suggest that airway remodeling in asthma involves the progressive accumulation of disorganized fibrillar collagen by airway fibroblasts. This study highlights the future potential clinical application of NLOM to assess airway remodeling in vivo.
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Affiliation(s)
- Leila B Mostaço-Guidolin
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada.,2Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Emmanuel T Osei
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada.,2Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jari Ullah
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada.,2Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Soheil Hajimohammadi
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada.,2Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - May Fouadi
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada.,2Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Xian Li
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada.,2Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Vicky Li
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada.,2Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Furquan Shaheen
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Chen Xi Yang
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Fanny Chu
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Darren J Cole
- 3School of Biomedical Engineering, Dalhousie University, Halifax, Nova Scotia, Canada; and
| | - Corry-Anke Brandsma
- 4Department of Pathology and Medical Biology.,5Groningen Research Institute of Asthma and COPD, and
| | - Irene H Heijink
- 4Department of Pathology and Medical Biology.,5Groningen Research Institute of Asthma and COPD, and.,6Department of Pulmonology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Geoffrey N Maksym
- 3School of Biomedical Engineering, Dalhousie University, Halifax, Nova Scotia, Canada; and
| | - David Walker
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Tillie-Louise Hackett
- 1Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada.,2Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
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Garofalakis A, Kruglik SG, Mansuryan T, Gillibert A, Thiberville L, Louradour F, Vever-Bizet C, Bourg-Heckly G. Characterization of a multicore fiber image guide for nonlinear endoscopic imaging using two-photon fluorescence and second-harmonic generation. JOURNAL OF BIOMEDICAL OPTICS 2019; 24:1-12. [PMID: 31646840 PMCID: PMC7000885 DOI: 10.1117/1.jbo.24.10.106004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 07/25/2019] [Indexed: 06/10/2023]
Abstract
Multiphoton microscopy (MPM) has the capacity to record second-harmonic generation (SHG) and endogenous two-photon excitation fluorescence (2PEF) signals emitted from biological tissues. The development of fiber-based miniaturized endomicroscopes delivering pulses in the femtosecond range will allow the transfer of MPM to clinical endoscopy. We present real-time SHG and 2PEF ex vivo images using an endomicroscope, which totally complies with clinical endoscopy regulations. This system is based on the proximal scanning of a commercial multicore image guide (IG). For understanding the inhomogeneities of the recorded images, we quantitatively characterize the IG at the single-core level during nonlinear excitation. The obtained results suggest that these inhomogeneities originate from the variable core geometries that, therefore, exhibit variable nonlinear and dispersive properties. Finally, we propose a method based on modulation of dispersion precompensation to address the image inhomogeneity issue and, as a proof of concept, we demonstrate its capability to improve the nonlinear image quality.
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Affiliation(s)
- Anikitos Garofalakis
- Sorbonne Université, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, Laboratoire Jean Perrin, Paris, France
| | - Sergei G. Kruglik
- Sorbonne Université, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, Laboratoire Jean Perrin, Paris, France
| | | | - André Gillibert
- Rouen University Hospital, Department of Biostatistics, Rouen, France
| | - Luc Thiberville
- CHU Rouen, Service de Pneumologie, Oncologie Thoracique et Soins Intensifs Respiratoires, Rouen, France
| | | | - Christine Vever-Bizet
- Sorbonne Université, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, Laboratoire Jean Perrin, Paris, France
| | - Genevieve Bourg-Heckly
- Sorbonne Université, Centre National de la Recherche Scientifique, Institut de Biologie Paris-Seine, Laboratoire Jean Perrin, Paris, France
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Snelgrove RJ, Patel DF. Zooming into the Matrix: Using Nonlinear Optical Microscopy to Visualize Collagen Remodeling in Asthmatic Airways. Am J Respir Crit Care Med 2019; 200:403-405. [PMID: 30985216 PMCID: PMC6701035 DOI: 10.1164/rccm.201904-0722ed] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Affiliation(s)
- Robert J Snelgrove
- 1National Heart and Lung InstituteImperial College LondonLondon, United Kingdom
| | - Dhiren F Patel
- 1National Heart and Lung InstituteImperial College LondonLondon, United Kingdom
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Zhuo S, Chen J. Stromal alterations as quantitative optical biomarkers of epithelial tumor progression. SCANNING 2014; 36:279-285. [PMID: 24347227 DOI: 10.1002/sca.21129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 10/28/2013] [Indexed: 06/03/2023]
Abstract
Stroma plays an important role during epithelial tumor progression. Probing stroma alteration may become an intrinsic indicator for evaluating epithelial tumor progression. In this review, we summarize our recent works on stromal alterations as quantitative optical biomarkers of epithelial tumor progression by use of nonlinear optical microscopy.
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Affiliation(s)
- Shuangmu Zhuo
- Institute of Laser and Optoelectronics Technology, Fujian Provincial Key Laboratory for Photonics Technology, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Normal University, Fuzhou, 350007, China
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Peyrot DA, Lefort C, Steffenhagen M, Mansuryan T, Ducourthial G, Abi-Haidar D, Sandeau N, Vever-Bizet C, Kruglik SG, Thiberville L, Louradour F, Bourg-Heckly G. Development of a nonlinear fiber-optic spectrometer for human lung tissue exploration. BIOMEDICAL OPTICS EXPRESS 2012; 3:840-53. [PMID: 22567579 PMCID: PMC3342191 DOI: 10.1364/boe.3.000840] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 03/23/2012] [Accepted: 03/23/2012] [Indexed: 05/12/2023]
Abstract
Several major lung pathologies are characterized by early modifications of the extracellular matrix (ECM) fibrillar collagen and elastin network. We report here the development of a nonlinear fiber-optic spectrometer, compatible with an endoscopic use, primarily intended for the recording of second-harmonic generation (SHG) signal of collagen and two-photon excited fluorescence (2PEF) of both collagen and elastin. Fiber dispersion is accurately compensated by the use of a specific grism-pair stretcher, allowing laser pulse temporal width around 70 fs and excitation wavelength tunability from 790 to 900 nm. This spectrometer was used to investigate the excitation wavelength dependence (from 800 to 870 nm) of SHG and 2PEF spectra originating from ex vivo human lung tissue samples. The results were compared with spectral responses of collagen gel and elastin powder reference samples and also with data obtained using standard nonlinear microspectroscopy. The excitation-wavelength-tunable nonlinear fiber-optic spectrometer presented in this study allows performing nonlinear spectroscopy of human lung tissue ECM through the elastin 2PEF and the collagen SHG signals. This work opens the way to tunable excitation nonlinear endomicroscopy based on both distal scanning of a single optical fiber and proximal scanning of a fiber-optic bundle.
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Affiliation(s)
- Donald A. Peyrot
- UPMC Univ. Paris 06, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
- CNRS, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
| | - Claire Lefort
- Faculté des Sciences et Techniques, Univ. Limoges, F-87060 Limoges, France
- XLIM, UMR CNRS 6172, F-87060 Limoges, France
| | - Marie Steffenhagen
- UPMC Univ. Paris 06, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
- CNRS, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
| | - Tigran Mansuryan
- Faculté des Sciences et Techniques, Univ. Limoges, F-87060 Limoges, France
- XLIM, UMR CNRS 6172, F-87060 Limoges, France
| | - Guillaume Ducourthial
- Faculté des Sciences et Techniques, Univ. Limoges, F-87060 Limoges, France
- XLIM, UMR CNRS 6172, F-87060 Limoges, France
| | - Darine Abi-Haidar
- UPMC Univ. Paris 06, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
- CNRS, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
| | - Nicolas Sandeau
- UPMC Univ. Paris 06, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
- CNRS, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
| | - Christine Vever-Bizet
- UPMC Univ. Paris 06, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
- CNRS, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
| | - Sergei G. Kruglik
- UPMC Univ. Paris 06, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
- CNRS, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
| | - Luc Thiberville
- Clinique de pneumologie, CHU Rouen, F-76000 Rouen, France
- Laboratoire LITIS-QuantIF EA 4108, Rouen Univ., F-76000 Rouen, France
| | - Frédéric Louradour
- Faculté des Sciences et Techniques, Univ. Limoges, F-87060 Limoges, France
- XLIM, UMR CNRS 6172, F-87060 Limoges, France
| | - Geneviève Bourg-Heckly
- UPMC Univ. Paris 06, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
- CNRS, FRE 3231, Laboratoire Jean Perrin, F-75005, Paris, France
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Chen J, Zhuo S, Jiang X, Zhu X, Zheng L, Xie S, Lin B, Zeng H. Multiphoton microscopy study of the morphological and quantity changes of collagen and elastic fiber components in keloid disease. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:051305. [PMID: 21639565 DOI: 10.1117/1.3569617] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Multiphoton microscopy was used to study the extracellular matrix of keloid at the molecular level without tissue fixation and staining. Direct imaging of collagen and elastin was achieved by second harmonic generation and two-photon excited fluorescence, respectively. The morphology and quantity of collagen and elastin in keloid were characterized and quantitatively analyzed in comparison to normal skin. The study demonstrated that in keloid, collagen content increased in both the upper dermis and the deep dermis, while elastin mostly showed up in the deep dermis and its quantity is higher compared to normal skin. This suggests the possibility that abnormal fibroblasts synthesized an excessive amount of collagen and elastin at the beginning of keloid formation, corresponding to the observed deep dermis, while after a certain time point, the abnormal fibroblast produced mostly collagen, corresponding to the observed upper dermis. The morphology of collagen and elastin in keloid was disrupted and presented different variations. In the deep dermis, elastic fibers showed node structure, while collagen showed obviously regular gaps between adjacent bundles. In the upper dermis, collagen bundles aligned in a preferred direction, while elastin showed as sparse irregular granules. This new molecular information provided fresh insight about the development process of keloid.
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Affiliation(s)
- Jianxin Chen
- Fujian Normal University, Institute of Laser and Optoelectronics Technology, Fujian Provincial Key Laboratory for Photonics Technology, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fuzhou 350007, China
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Two-photon microscopy for non-invasive, quantitative monitoring of stem cell differentiation. PLoS One 2010; 5:e10075. [PMID: 20419124 PMCID: PMC2855700 DOI: 10.1371/journal.pone.0010075] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Accepted: 03/04/2010] [Indexed: 11/24/2022] Open
Abstract
Background The engineering of functional tissues is a complex multi-stage process, the success of which depends on the careful control of culture conditions and ultimately tissue maturation. To enable the efficient optimization of tissue development protocols, techniques suitable for monitoring the effects of added stimuli and induced tissue changes are needed. Methodology/Principal Findings Here, we present the quantitative use of two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) as a noninvasive means to monitor the differentiation of human mesenchymal stem cells (hMSCs) using entirely endogenous sources of contrast. We demonstrate that the individual fluorescence contribution from the intrinsic cellular fluorophores NAD(P)H, flavoproteins and lipofuscin can be extracted from TPEF images and monitored dynamically from the same cell population over time. Using the redox ratio, calculated from the contributions of NAD(P)H and flavoproteins, we identify distinct patterns in the evolution of the metabolic activity of hMSCs maintained in either propagation, osteogenic or adipogenic differentiation media. The differentiation of these cells is mirrored by changes in cell morphology apparent in high resolution TPEF images and by the detection of collagen production via SHG imaging. Finally, we find dramatic increases in lipofuscin levels in hMSCs maintained at 20% oxygen vs. those in 5% oxygen, establishing the use of this chromophore as a potential biomarker for oxidative stress. Conclusions/Significance In this study we demonstrate that it is possible to monitor the metabolic activity, morphology, ECM production and oxidative stress of hMSCs in a non-invasive manner. This is accomplished using generally available multiphoton microscopy equipment and simple data analysis techniques, such that the method can widely adopted by laboratories with a diversity of comparable equipment. This method therefore represents a powerful tool, which enables researchers to monitor engineered tissues and optimize culture conditions in a near real time manner.
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Lu K, Chen J, Zhuo S, Zheng L, Jiang X, Zhu X, Zhao J. Multiphoton laser scanning microscopy of localized scleroderma. Skin Res Technol 2010; 15:489-95. [PMID: 19832963 DOI: 10.1111/j.1600-0846.2009.00395.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND/PURPOSE A real-time, non-invasive method will confer a benefit for the diagnosis and treatment of localized scleroderma (LS) in the clinic. The aim of this work was to demonstrate the potential of multiphoton laser scanning microscopy (MPLSM) for diagnosing LS and monitoring the treatment response in vivo. METHODS Three sclerodermatous skin specimens and two normal skin specimens were investigated using MPLSM based on two-photon excitation fluorescence (TPEF) and second harmonic generation (SHG). MPLSM consists of a femtosecond Ti:sapphire laser and a scanning inverted microscope. Several parameters such as the epidermal thickness, the orientation ratio index of collagen bundles (ORICB), the spacing of collagen fibrin as well as the SHG to TPEF index of the dermis (STID) were developed to quantitatively discriminate the sclerodermatous skin from the normal skin. RESULTS The morphological differences were visualized obviously in the TPEF/SHG images of human skin (normal and sclerodermatous). The values of the developed parameters in normal skin were significantly different from that in sclerodermatous skin (P<0.05). CONCLUSION MPLSM could discriminate the sclerodermatous skin from the normal skin. With the advent of the clinical portability of typical MPLSM, this technique has great potential for application in the in vivo diagnosis of LS as well as for monitoring the treatment response.
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Affiliation(s)
- Kecheng Lu
- Institute of Laser and Optoelectronics Technology, Fujian Provincial Key Laboratory for Photonics Technology, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Normal University, Fuzhou, China
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Zhuo S, Chen J, Xie S, Hong Z, Jiang X. Extracting diagnostic stromal organization features based on intrinsic two-photon excited fluorescence and second-harmonic generation signals. JOURNAL OF BIOMEDICAL OPTICS 2009; 14:020503. [PMID: 19405709 DOI: 10.1117/1.3088029] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Intrinsic two-photon excited fluorescence (TPEF) and second-harmonic generation (SHG) signals are shown to differentiate between normal and neoplastic human esophageal stroma. It was found that TPEF and SHG signals from normal and neoplastic stroma exhibit different organization features, providing quantitative information about the biomorphology and biochemistry of tissue. By comparing normal with neoplastic stroma, there were significant differences in collagen-related changes, elastin-related changes, and alteration in proportions of matrix molecules, giving insight into the stromal changes associated with cancer progression and providing substantial potential to be applied in vivo to the clinical diagnosis of epithelial precancers and cancers.
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