Name: an ex vivo tissue culture model for fibrovascular complications in proliferative diabetic retinopathy
Uploaded: 2019-01-25T15:00:00
Description: Watch this Scientific Journal Video about An Ex Vivo Tissue Culture Model for Fibrovascular Complications in Proliferative Diabetic Retinopathy at JoVE.com

The authors are most grateful to the medical and surgical retina colleagues, nurses and whole staff of the Diabetic Unit and Vitreoretinal Surgery Unit at the Department of Ophthalmology, Helsinki University Hospital for actively participating in the recruitment of patients. We thank Biomedicum Molecular Imaging Unit for imaging facilities. We thank Anastasiya Chernenko for excellent technical assistance. This study was supported by grants from the Academy of Finland (KL), University of Helsinki (KL), Sigrid Juselius Foundation (KL), K. Albin Johansson Foundation (KL), Finnish Cancer Institute (KL), Karolinska Institutet (KL), Finnish Eye Foundation (SL), Eye and Tissue Bank Foundation (SL), Mary and Georg C. Ehrnrooth Foundation (SL), and HUCH Clinical Research Grants (TYH2018127 after TYH2016230, SL), Diabetes Research Foundation (SL, KL, AK, EG) as well as the Doctoral Programme in Biomedicine (EG).

This research was approved by the Institutional Review Board and Ethical committee of Helsinki University Hospital. Signed informed consent was obtained from each patient.
1. Preparation of Solutions, Media and Equipment
<ol>
	<li>Prepare the following equipment prior to collection of the fibrovascular tissue (FT) to ensure rapid processing.
	<ol>
		<li>Sterile-autoclave two microdissection tweezers.</li>
		<li>Prepare 1x phosphate-buffered saline (PBS) by dissolving 1 pre-weighed PBS tablet...

<ol>
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V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mini+Review:+Changes+in+the+Incidence+of+and+Progression+to+Proliferative+and+Sight-Threatening+Diabetic+Retinopathy+Over+the+Last+30+Years.">Mini Review: Changes in the Incidence of and Progression to Proliferative and Sight-Threatening Diabetic Retinopathy Over the Last 30 Years.</a> Ophthalmic Epidemiology. 24 (2), 73-80 (2017).</li><li>Loukovaara, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Indications+of+lymphatic+endothelial+differentiation+and+endothelial+progenitor+cell+activation+in+the+pathology+of+proliferative+diabetic+retinopathy.">Indications of lymphatic endothelial differentiation and endothelial progenitor cell activation in the pathology of proliferative diabetic retinopathy.</a> Acta Ophthalmologica. 93 (6), 512-523 (2015).</li><li>Stitt, A. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+progress+in+understanding+and+treatment+of+diabetic+retinopathy.">The progress in understanding and treatment of diabetic retinopathy.</a> Progress in Retinal and Eye Research. 51, 156-186 (2016).</li><li>Duh, E. J., Sun, J. K., Stitt, A. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diabetic+retinopathy:+current+understanding,+mechanisms,+and+treatment+strategies.">Diabetic retinopathy: current understanding, mechanisms, and treatment strategies.</a> JCI Insight. 2 (14), (2017).</li><li>Gross, J. 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S., Montesano, R., Mandriota, S. J., Orci, L., Vassalli, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Angiogenesis:+a+paradigm+for+balanced+extracellular+proteolysis+during+cell+migration+and+morphogenesis.">Angiogenesis: a paradigm for balanced extracellular proteolysis during cell migration and morphogenesis.</a> Enzyme, Protein. 49 (1-3), 138-162 (1996).</li><li>Lafleur, M. A., Handsley, M. M., Knauper, V., Murphy, G., Edwards, D. 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M., Struyf, S., Opdenakker, G., Van Damme, J., Geboes, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Expression+of+stem+cell+factor/c-kit+signaling+pathway+components+in+diabetic+fibrovascular+epiretinal+membranes.">Expression of stem cell factor/c-kit signaling pathway components in diabetic fibrovascular epiretinal membranes.</a> Molecular Vision. 16, 1098-1107 (2010).</li><li>Loukovaara, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ang-2+upregulation+correlates+with+increased+levels+of+MMP-9,+VEGF,+EPO+and+TGFbeta1+in+diabetic+eyes+undergoing+vitrectomy.">Ang-2 upregulation correlates with increased levels of MMP-9, VEGF, EPO and TGFbeta1 in diabetic eyes undergoing vitrectomy.</a> Acta Ophthalmologica. 91 (6), 531-539 (2013).</li><li>Sugiyama, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EphA2+cleavage+by+MT1-MMP+triggers+single+cancer+cell+invasion+via+homotypic+cell+repulsion.">EphA2 cleavage by MT1-MMP triggers single cancer cell invasion via homotypic cell repulsion.</a> Journal of Cell Biology. 201 (3), 467-484 (2013).</li><li>Tatti, O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MMP16+Mediates+a+Proteolytic+Switch+to+Promote+Cell-Cell+Adhesion,+Collagen+Alignment,+and+Lymphatic+Invasion+in+Melanoma.">MMP16 Mediates a Proteolytic Switch to Promote Cell-Cell Adhesion, Collagen Alignment, and Lymphatic Invasion in Melanoma.</a> Cancer Research. 75 (10), 2083-2094 (2015).</li><li>Zudaire, E., Gambardella, L., Kurcz, C., Vermeren, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+computational+tool+for+quantitative+analysis+of+vascular+networks.">A computational tool for quantitative analysis of vascular networks.</a> PLoS One. 6 (11), e27385 (2011).</li><li>Senger, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+framework+for+angiogenesis:+a+complex+web+of+interactions+between+extravasated+plasma+proteins+and+endothelial+cell+proteins+induced+by+angiogenic+cytokines.">Molecular framework for angiogenesis: a complex web of interactions between extravasated plasma proteins and endothelial cell proteins induced by angiogenic cytokines.</a> American Journal of Pathology. 149 (1), 1-7 (1996).</li><li>Senger, D. R., Davis, G. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Angiogenesis.">Angiogenesis.</a> Cold Spring Harbor Perspectives in Biology. 3 (8), a005090 (2011).</li><li>Bishop, P. 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Considering the importance of relevant tissue microenvironment for reliable functional cell and molecular mechanistic results, it is imperative to find appropriate experimental models that provide this tissue environment. The herein described ex vivo PDR culture model for the fibrin-embedded FTs allows the investigation of the mechanisms of PDR pathophysiology in the native, complex and multicellular context of the PDR clinical samples.
Critical steps within the protocol are the prope...

DR is a serious ocular complication of diabetes, a disease that has reached enormous proportions in the last three decades1. Twenty years after diagnosis, virtually every patient with type 1 diabetes and 60% of patients with type 2 diabetes present signs of retinopathy, making diabetes per se one of the leading causes of blindness in working age adults2. According to the level of microvascular degeneration and ischemic damage, DR is classified into non-proliferative DR (non-PDR) and proliferative DR (PDR). The end-stage disease, PDR, is characterized by ischemia- and inflammation-induced neovascularization and fibrotic responses at the vitreoretinal interface. In untreated conditions, these processes will lead to blindness due to vitreous hemorrhage, retinal fibrosis, tractional retinal detachment, and neovascular glaucoma3,4. Despite recent advances, current treatment options target only DR stages, including diabetic macular edema and PDR, when retinal damage has already ensued. Moreover, a great proportion of DR patients does not benefit from current treatment armamentarium, indicating an urgent need for improved therapies4,5,6.
Multiple other in vivo disease/developmental models and diabetic animal models have been developed to date, but none of them recapitulates the full range of pathologic features observed in human PDR7,8. Moreover, increasing evidence indicates that treatment responses are tightly connected to the ECM composition as well as the spatial arrangement and interaction between the cellular and acellular microenvironment9. We, therefore, set out to develop a clinically relevant model of human PDR by utilizing the FT pathological material that is commonly excised from eyes undergoing vitrectomy as part of the surgical management of PDR10.
This manuscript describes the protocol for the 3D ex vivo culture and characterization of the surgically-excised, PDR patient-derived pathological FT. The method described here has been used in a recent publication that demonstrated successful deconstruction of the native 3D PDR tissue landscape, and recapitulation of features of PDR pathophysiology including angiogenic and fibrotic responses of the abnormal vascular structures11. This model also revealed novel features that cannot be easily appreciated from thin histological sections, such as spatially confined apoptosis and proliferation as well as vascular islet formation11. Vitreous fluid has been successfully used by others on 3D endothelial spheroid cultures to evaluate its angiogenic potential and the efficacy of angiostatic molecules12. When combined with an in vitro 3D lymphatic endothelial cell (LEC) spheroid sprouting assay using PDR vitreous as stimulant, our model revealed the contribution of both soluble vitreal factors as well as local cues within the neovascular tissue to the as yet poorly understood LEC involvement in PDR pathophysiology3,11. In the management of PDR, vitreoretinal surgery is a routinely performed yet challenging procedure. As surgical instrumentations and techniques are seeing continuous advancement and sophistication, timely and conservative removal of fibrovascular proliferative specimen not only improves vision outcome but also provides invaluable tissue material for the investigation of PDR pathophysiology and treatment responses in the complex translational aspects of the live human tissue microenvironment.

<table>
	<tbody>
		<tr>
			<td>Material</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Microforceps</td>
			<td>Medicon</td>
			<td>07.60.03</td>
			<td>Used for handling the FTs</td>
		</tr>
		<tr>
			<td>Disposable Scalpels - Sterile</td>
			<td>Swann-Morton</td>
			<td>0513</td>
			<td>Used for FT dissection</td>
		</tr>
		<tr>
			<td>Culture dish, vented, 28 ml (60mm)</td>
			<td>Greiner Bio-One</td>
			<td>391-3210</td>
			<td>Used for dissection and for testing fibrin gel formation</td>
		</tr>
		<tr>
			<td>Cell culture plates, 12-well</td>
			<td>Greiner Bio-One</td>
			<td>392-0049</td>
			<td>Used for FT dissection and whole-mount immunofluorescence</td>
		</tr>
		<tr>
			<td>Reagent/centrifuge tube with screw cap, 15 mL</td>
			<td>Greiner Bio-One</td>
			<td>391-3477</td>
			<td></td>
		</tr>
		<tr>
			<td>Reagent/centrifuge tube with screw cap, 50 mL</td>
			<td>Greiner Bio-One</td>
			<td>525-0384</td>
			<td></td>
		</tr>
		<tr>
			<td>Millex-GV Syringe Filter Unit, 0.22&#160;&#181;m, PVDF</td>
			<td>Millipore</td>
			<td>SLGV033RS</td>
			<td>Used to sterile-filter the fibrinogen solution</td>
		</tr>
		<tr>
			<td>Syringe, 10 mL</td>
			<td>Braun</td>
			<td>4606108V</td>
			<td>Used to sterile-filter the fibrinogen solution</td>
		</tr>
		<tr>
			<td>Polypropylene Microcentrifuge Tubes, 1.5 mL</td>
			<td>Fisher</td>
			<td>FB74031</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell-Culture Treated Multidishes, 24-well</td>
			<td>Nunc</td>
			<td>142475</td>
			<td>Used for casting the FT/fibrin gels for native FT characterization and ex vivo culture</td>
		</tr>
		<tr>
			<td>Cell culture plates, 96-well, U-bottom</td>
			<td>Greiner Bio-One</td>
			<td>392-0019</td>
			<td>Used for whole-mount immunofluorescence</td>
		</tr>
		<tr>
			<td>Round/Flat Spatulas, Stainless Steel</td>
			<td>VWR</td>
			<td>82027-528</td>
			<td>Used for whole-mount immunofluorescence</td>
		</tr>
		<tr>
			<td>Coverslips 22x22mm #1</td>
			<td>Menzel/Fisher</td>
			<td>15727582</td>
			<td>Used for mounting</td>
		</tr>
		<tr>
			<td>Microscope slides</td>
			<td>Fisher</td>
			<td>Kindler K102</td>
			<td>Used for mounting</td>
		</tr>
		<tr>
			<td>Absorbent paper</td>
			<td>VWR</td>
			<td>115-0202</td>
			<td>Used for mounting</td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Reagents</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>PBS tablets</td>
			<td>Medicago</td>
			<td>09-9400-100</td>
			<td>Used for preparing 1x PBS</td>
		</tr>
		<tr>
			<td>Fibrinogen, Plasminogen-Depleted, Human Plasma</td>
			<td>Calbiochem</td>
			<td>341578</td>
			<td></td>
		</tr>
		<tr>
			<td>Hanks Balanced Salt Solution</td>
			<td>Sigma-Aldrich</td>
			<td>H9394-500ML</td>
			<td>Used for preparing the fibrinogen and TA solution</td>
		</tr>
		<tr>
			<td>Fetal bovine serum</td>
			<td>Gibco</td>
			<td>10270106</td>
			<td>Used for preparing the blocking solution</td>
		</tr>
		<tr>
			<td>Human Serum</td>
			<td>Sigma-Aldrich</td>
			<td>H4522</td>
			<td>Aliquoted in -20 &#176;C, thaw before preparing the ex vivo culture media</td>
		</tr>
		<tr>
			<td>Gentamicin Sulfate 10mg/ml</td>
			<td>Biowest</td>
			<td>L0011-100</td>
			<td></td>
		</tr>
		<tr>
			<td>Endothelial cell media MV Kit</td>
			<td>Promocell</td>
			<td>C-22120</td>
			<td>Contains 500 ml of Endothelial Cell Growth Medium MV, 25 mL of fetal calf serum, 2 mL of endothelial cell growth supplement,&#160; 500 &#956;L of recombinant human epidermal growth factor (10 &#956;g/ mL) and 500 &#956;L of hydrocortisone (1 g/ mL)</td>
		</tr>
		<tr>
			<td>Sodium azide</td>
			<td>Sigma-Aldrich</td>
			<td>S2002</td>
			<td>Used for storage of the native and ex vivo cultured FTs. TOXIC: wear protective gloves and/or clothing, and eye and/or face protection. Use in fume hood.</td>
		</tr>
		<tr>
			<td>Acetone</td>
			<td>Sigma-Aldrich</td>
			<td>32201-2.5L-M</td>
			<td>Used to prepare the post-fixation solution. HARMFUL: wear protective gloves and/or clothing. Use in fume hood.</td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>Sigma-Aldrich</td>
			<td>32213</td>
			<td>Used to prepare the post-fixation solution. TOXIC: wear protective gloves and/or clothing. Use in fume hood.</td>
		</tr>
		<tr>
			<td>Triton X-100 (octyl phenol ethoxylate)</td>
			<td>Sigma-Aldrich</td>
			<td>T9284</td>
			<td>Used for whole-mount immunofluorescence. HARMFUL: wear protective gloves and/or clothing.</td>
		</tr>
		<tr>
			<td>Hoechst 33342, 20mM</td>
			<td>Life Technologies</td>
			<td>62249</td>
			<td>For nuclei counterstaining. HARMFUL: wear protective gloves and/or clothing, and eye and/or face protection.</td>
		</tr>
		<tr>
			<td>VECTASHIELD Antifade Mounting Medium</td>
			<td>Vector Laboratories</td>
			<td>H-1000</td>
			<td>Wear protective gloves and/or clothing, and eye protection. Use in fume hood.</td>
		</tr>
		<tr>
			<td>VECTASHIELD Antifade Mounting Medium with DAPI</td>
			<td>Vector Laboratories</td>
			<td>H-1200</td>
			<td>Mounting medium with nuclei counterstaining. Wear protective gloves and/or clothing, and eye protection. Use in fume hood.</td>
		</tr>
		<tr>
			<td>Eukitt Quick-hardening mounting medium</td>
			<td>Sigma-Aldrich</td>
			<td>03989-100ml</td>
			<td>TOXIC: Wear protective gloves and/or clothing, and eye protection. Use in fume hood.</td>
		</tr>
		<tr>
			<td>Thrombin from bovine plasma, lyophilized powder</td>
			<td>Sigma-Aldrich</td>
			<td>T9549-500UN&#160;</td>
			<td>Dissolve at 100 units/ mL, aliquote and store at -20 &#176;C, avoid repeated freeze/ thaw</td>
		</tr>
		<tr>
			<td>Aprotinin from bovine lung, lyophilized powder</td>
			<td>Sigma</td>
			<td>A3428</td>
			<td>Dissolve at 50 mg/ mL, aliquote and store at -20 &#176;C, avoid repeated freeze/ thaw</td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Growth factors</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Recombinant human VEGFA</td>
			<td>R&#38;D Systems</td>
			<td>293-VE-010</td>
			<td>50 ng/ mL final concentration</td>
		</tr>
		<tr>
			<td>Recombinant human VEGFC</td>
			<td>R&#38;D Systems</td>
			<td>752-VC-025</td>
			<td>200 ng/ mL final concentration</td>
		</tr>
		<tr>
			<td>Recombinant human TGF&#946;</td>
			<td>Millipore</td>
			<td>GF346</td>
			<td>1 ng/ mL final concentration</td>
		</tr>
		<tr>
			<td>Recombinant human bFGF</td>
			<td>Millipore</td>
			<td>01-106</td>
			<td>50 ng/ mL final concentration</td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Primary antibodies</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>CD31 (JC70A)</td>
			<td>Dako</td>
			<td>M0823</td>
			<td>Used at 1:100 dilution, Donkey anti Mouse Alexa 488 Secondary Ab</td>
		</tr>
		<tr>
			<td>CD34 (QBEND10)</td>
			<td>Dako</td>
			<td>M716501-2</td>
			<td>Used at 1:100 dilution, Donkey anti Mouse Alexa 488 Secondary Ab</td>
		</tr>
		<tr>
			<td>CD45 (2B11+PD7/26)</td>
			<td>Dako</td>
			<td>M070129-2</td>
			<td>Used at 1:100 dilution, Donkey anti Mouse Alexa 488 Secondary Ab</td>
		</tr>
		<tr>
			<td>CD68</td>
			<td>ImmunoWay</td>
			<td>RLM3161</td>
			<td>Used at 1:100 dilution, Donkey anti Mouse Alexa 488 Secondary Ab</td>
		</tr>
		<tr>
			<td>Cleaved caspase-3 (5A1E)</td>
			<td>Cell Signalling</td>
			<td>9664</td>
			<td>Used at 1:200 dilution, Goat anti Rabbit Alexa 594 Secondary Ab</td>
		</tr>
		<tr>
			<td>ERG (EP111)</td>
			<td>Dako</td>
			<td>M731429-2</td>
			<td>Used at 1:100 dilution, Goat anti Rabbit Alexa 594 Secondary Ab</td>
		</tr>
		<tr>
			<td>GFAP</td>
			<td>Dako</td>
			<td>Z0334</td>
			<td>Used at 1:100 dilution, Goat anti Rabbit Alexa 594 Secondary Ab</td>
		</tr>
		<tr>
			<td>Ki67</td>
			<td>Leica Microsystems</td>
			<td>NCL-Ki67p</td>
			<td>Used at 1:1500 dilution, Goat anti Rabbit Alexa 594 Secondary Ab</td>
		</tr>
		<tr>
			<td>Lyve1</td>
			<td>R&#38;D Systems</td>
			<td>AF2089</td>
			<td>Used at 1:100 dilution, Donkey anti Goat Alexa 568 Secondary Ab</td>
		</tr>
		<tr>
			<td>NG2</td>
			<td>Millipore</td>
			<td>AB5320</td>
			<td>Used at 1:100 dilution, Goat anti Rabbit Alexa 594 Secondary Ab</td>
		</tr>
		<tr>
			<td>Prox1</td>
			<td>ReliaTech</td>
			<td>102-PA32</td>
			<td>Used at 1:200 dilution, Goat anti Rabbit Alexa 568 Secondary Ab</td>
		</tr>
		<tr>
			<td>Prox1</td>
			<td>R&#38;D Systems</td>
			<td>AF2727</td>
			<td>Used at 1:40 dilution, Chicken anti Goat Alexa 594 Secondary Ab</td>
		</tr>
		<tr>
			<td>VEGFR3 (9D9F9)</td>
			<td>Millipore</td>
			<td>MAB3757</td>
			<td>Used at 1:100 dilution, Donkey anti Mouse Alexa 488 Secondary Ab</td>
		</tr>
		<tr>
			<td>&#945;-SMA (1A4)</td>
			<td>Sigma</td>
			<td>C6198</td>
			<td>Used at 1:400 dilution, Cy3 conjugated</td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Secondary antibodies</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa Fluor488 Donkey Anti-Mouse IgG</td>
			<td>Life Technologies</td>
			<td>A-21202</td>
			<td>Used at 1:500 dilution</td>
		</tr>
		<tr>
			<td>Alexa Fluor594 Goat Anti-Rabbit IgG</td>
			<td>Invitrogen</td>
			<td>A-11012</td>
			<td>Used at 1:500 dilution</td>
		</tr>
		<tr>
			<td>Alexa Fluor568 Donkey anti-Goat IgG</td>
			<td>Thermo Scientific</td>
			<td>A-11057</td>
			<td>Used at 1:500 dilution</td>
		</tr>
		<tr>
			<td>Alexa Fluor568 Goat anti-Rabbit IgG</td>
			<td>Thermo Scientific</td>
			<td>A-11036</td>
			<td>Used at 1:500 dilution</td>
		</tr>
		<tr>
			<td>Alexa Fluor594 Chicken Anti-Goat IgG</td>
			<td>Molecular Probes</td>
			<td>A-21468</td>
			<td>Used at 1:500 dilution</td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Microscopes</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Axiovert 200 inverted epifluorescence microscope</td>
			<td>Zeiss</td>
			<td></td>
			<td>For imaging of the fresh and fibrin-embedded FT</td>
		</tr>
		<tr>
			<td>SZX9 upright dissection stereomicroscope</td>
			<td>Olympus</td>
			<td></td>
			<td>For FT dissection</td>
		</tr>
		<tr>
			<td>LSM 780 confocal microscope</td>
			<td>Zeiss</td>
			<td></td>
			<td>For imaging of whole-mount immunostained FT</td>
		</tr>
		<tr>
			<td>AxioImager.Z1 upright epifluorescence microscope with Apotome</td>
			<td>Zeiss</td>
			<td></td>
			<td>For imaging of whole-mount immunostained FT</td>
		</tr>
	</tbody>
</table>

an ex vivo tissue culture model for fibrovascular complications in proliferative diabetic retinopathy

Diabetic retinopathy (DR) is the most common microvascular complication of diabetes and one of the leading causes of blindness in working-age adults. No current animal models of diabetes and oxygen-induced retinopathy develop the full-range progressive changes manifested in human proliferative diabetic retinopathy (PDR). Therefore, understanding of the disease pathogenesis and pathophysiology has relied largely on the use of histological sections and vitreous samples in approaches that only provide steady-state information on the involved pathogenic factors. Increasing evidence indicates that dynamic cell-cell and cell-extracellular matrix (ECM) interactions in the context of three-dimensional (3D) microenvironments are essential for the mechanistic and functional studies towards the development of new treatment strategies. Therefore, we hypothesized that the pathological fibrovascular tissue surgically excised from eyes with PDR could be utilized to reliably unravel the cellular and molecular mechanisms of this devastating disease and to test the potential for novel clinical interventions. Towards this end, we developed a novel method for 3D ex vivo culture of surgically-excised patient-derived fibrovascular tissue (FT), which will serve as a relevant model of human PDR pathophysiology. The FTs are dissected into explants and embedded in fibrin matrix for ex vivo culture and 3D characterization. Whole-mount immunofluorescence of the native FTs and end-point cultures allows thorough investigation of tissue composition and multicellular processes, highlighting the importance of 3D tissue-level characterization for uncovering relevant features of PDR pathophysiology. This model will allow the simultaneous assessment of molecular mechanisms, cellular/tissue processes and treatment responses in the complex context of dynamic biochemical and physical interactions within the PDR tissue architecture and microenvironment. Since this model recapitulates PDR pathophysiology, it will also be amenable for testing or developing new treatments.

Deeper understanding of the PDR fibrovascular tissue properties and protein expression has relied mainly on vitreous samples and thin histological FT sections3,15,16,17. To develop a method for thorough investigation of the 3D tissue organization and multicellular physiopathological processes of PDR, we set out to utilize the surgically excised, patient-derived ...

Watch this Scientific Journal Video about An Ex Vivo Tissue Culture Model for Fibrovascular Complications in Proliferative Diabetic Retinopathy at JoVE.com

An Ex Vivo Tissue Culture Model for Fibrovascular Complications in Proliferative Diabetic Retinopathy

Here, we present a protocol to study the pathophysiology of proliferative diabetic retinopathy by using patient-derived, surgically-excised, fibrovascular tissues for three-dimensional native tissue characterization and ex vivo culture. This ex vivo culture model is also amenable for testing or developing new treatments.

Diabetic retinopathy (DR) is the most common microvascular complication of diabetes and one of the leading causes of blindness in working-age adults. No ...

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JoVE Journal

Medicine

Ex Vivo Culture of Patient Tissue &amp; Examination of Gene Delivery

Ex Vivo Culture of Patient Tissue & Examination of Gene Delivery

This video describes the use of patient tissue as an ex vivo model for the study of gene delivery.  Fresh patient tissue obtained at the time of surgery ...

Ex Vivo Infection of Live Tissue with Oncolytic Viruses

Ex Vivo Infection of Live Tissue with Oncolytic Viruses

Oncolytic Viruses (OVs) are novel therapeutics that selectively replicate in and kill tumor cells1. Several clinical trials evaluating the effectiveness ...

An Ex vivo Model to Study Hormone Action in the Human Breast

An Ex vivo Model to Study Hormone Action in the Human Breast

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Human Dupuytren's Ex Vivo Culture for the Study of Myofibroblasts and Extracellular Matrix Interactions

Human Dupuytren's Ex Vivo Culture for the Study of Myofibroblasts and Extracellular Matrix Interactions

Organ fibrosis or &#8220;scarring&#8221; is known to account for a high death toll due to the extensive amount of disorders and organs affected (from ...

Creation and Transplantation of an Adipose-derived Stem Cell (ASC) Sheet in a Diabetic Wound-healing Model

Creation and Transplantation of an Adipose-derived Stem Cell ASC Sheet in a Diabetic Wound-healing Model

Artificial skin has achieved considerable therapeutic results in clinical practice. However, artificial skin treatments for wounds in diabetic patients ...

Breast Milk Enhances Growth of Enteroids: An Ex Vivo Model of Cell Proliferation

Breast Milk Enhances Growth of Enteroids: An Ex Vivo Model of Cell Proliferation

Human small intestinal enteroids are derived from the crypts and when grown in a stem cell niche contain all of the epithelial cell types. The ability to ...

Assessment of Plasma Coagulation on Liver Tissue in a Large Animal Model In Vivo

Assessment of Plasma Coagulation on Liver Tissue in a Large Animal Model In Vivo

Plasma coagulation as a form of electrocautery is used in liver surgery for decades to seal the large liver cut surface after major hepatectomy to prevent ...

A Small Animal Model of Ex Vivo Normothermic Liver Perfusion

A Small Animal Model of Ex Vivo Normothermic Liver Perfusion

There is a significant shortage of liver allografts available for transplantation, and in response the donor criteria have been expanded. As a result, ...

Ex Vivo Corneal Organ Culture Model for Wound Healing Studies

The cornea has been used extensively as a model system to study wound healing. The ability to generate and utilize primary mammalian cells in two ...

Preclinical Model of Hind Limb Ischemia in Diabetic Rabbits

Peripheral vascular disease is a widespread clinical problem that affects millions of patients worldwide. A major consequence of peripheral vascular ...