eoe sub articles

EoE Sub Articles

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. Sterilization
<ol>
	<li>CRITICAL STEP: Disinfect all forceps and scissors by soaking for 1 h in 5% (v/v) solution of Distel in distilled water, clean with a brush, rinse with tap water and sterilize in an oven at 185 &#176;C for a minimum of 2 h.</li>
	<li>Sterilize all other glassware and reagents by autoclaving at 121 &#176;C f...

corneoscleral button isolation: a surgical procedure to obtain corneoscleral button from porcine eye

Source: Okurowska, K., et al. <a href="https://www.jove.com/v/61156">Establishing a Porcine Ex Vivo Cornea Model for Studying Drug Treatments against Bacterial Keratitis.</a> J. Vis. Exp. (2020).
In this video, we show a procedure to surgically isolate the corneoscleral button to generate an ex vivo porcine cornea model. The model is helpful for histological, pathological, and pharmacological studies due to its similarity to the human eye.

Corneoscleral Button Isolation: A Surgical Procedure to Obtain Corneoscleral Button from Porcine Eye

Source: Okurowska, K., et al. Establishing a Porcine Ex Vivo Cornea Model for Studying Drug Treatments against Bacterial Keratitis. J. Vis. Exp. (2020).
...

The anterior portion of the eye is covered by the cornea - a transparent layer that allows the transmission of light rays. The cornea extends into the sclera - a white protective tissue around the eye. The part of the eye that consists of the cornea surrounded by a thin ring of the sclera is the corneoscleral button.
To excise the corneoscleral button, place an intact porcine eye on a Petri dish. Remove the conjunctiva - a mucilaginous covering around the sclera - along with the surrounding extraocular muscles to access the scleral cover. Treat the eye with a suitable disinfectant solution to remove any contaminating microorganisms from the eye&#39;s surface.&#160;
Wash off the disinfectant with a buffer solution. Transfer the disinfected eye to a fresh culture dish. Make an incision on the sclera near the corneal boundary. Using this opening, make a complete circumferential cut to divide the eye into two fragments.
Visualize the interior side of the frontal segment to locate the uveal coat attached to the sclera. This tissue consists of pigmented iris, a ring-shaped ciliary body, and a portion of the vascular choroid layer.&#160; Detach the uvea to visualize the corneoscleral layer. Store the button in a sterile buffer solution for further assays.&#160;

corneoscleral-button-isolation-surgical-procedure-to-obtain

Research

JoVE Encyclopedia of Experiments

Biology

Large Animal Models

Porcine

Preparation of Mouse Retinal Cryo-sections for Immunohistochemistry

Preparation of high-quality mouse eye sections for immunohistochemistry (IHC) is critical for assessing the retinal structure and function and for determining the mechanisms underlying retinal diseases. Maintaining structural integrity throughout the tissue preparation is vital for obtaining reproducible retinal IHC data but can be challenging due to the fragility and complexity of retinal cytoarchitecture. Strong fixatives like 10% formalin or Bouin's solution optimally preserve the retinal structure, they often impede IHC analysis by enhancing the background fluorescence and/or diminishing antibody-epitope interactions, a process known as epitope masking. Milder fixatives, on the other hand, like 4% paraformaldehyde, reduces background fluorescence and epitope-masking, meticulous dissection techniques must be utilized to preserve the retinal structure. In this article, we present a comprehensive method to prepare mouse ocular posterior cups for IHC that is sufficient to preserve most antibody-epitope interactions without loss of retinal structural integrity. We include representative IHC with antibodies to various retinal cell type markers to illustrate tissue preservation and orientation under optimal and sub-optimal conditions. Our goal is to optimize IHC studies of the retina by providing a complete protocol from ocular posterior cup dissection to IHC.

This report describes comprehensive methods for preparing frozen mouse retina sections for immunohistochemistry (IHC). Methods described include dissection of the ocular posterior cup, paraformaldehyde fixation, embedding in Optimal Cutting Temperature (OCT) media and tissue orientation, sectioning and immunostaining.

Preparation of high-quality mouse eye sections for immunohistochemistry (IHC) is critical for assessing the retinal structure and function and for ...

JoVE Journal

Neuroscience

Porcine Corneal Tissue Explant to Study the Efficacy of Herpes Simplex Virus-1 Antivirals

Viruses and bacteria can cause a variety of ocular surface defects and degeneration such as wounds and ulcers through corneal infection. With a seroprevalence that ranges from 60-90% worldwide, the Herpes Simplex Virus type-1 (HSV-1) commonly causes mucocutaneous lesions of the orofacial region which also manifest as lesions and infection-associated blindness. While current antiviral drugs are effective, emergence of resistance and persistence of toxic side-effects necessitates development of novel antivirals against this ubiquitous pathogen. Although in vitro assessment provides some functional data regarding an emerging antiviral, they do not demonstrate the complexity of ocular tissue in vivo. However, in vivo studies are expensive and require trained personnel, especially when working with viral agents. Hence ex vivo models are efficient yet inexpensive steps for antiviral testing. Here we discuss a protocol to study infection by HSV-1 using porcine corneas ex vivo and a method to treat them topically using existing and novel antiviral drugs. We also demonstrate the method to perform a plaque assay using HSV-1. The methods detailed may be used to conduct similar experiments to study infections that resemble the HSV-1 pathogen.

We describe the use of a porcine cornea to test the antiviral efficacy of experimental drugs.

Viruses and bacteria can cause a variety of ocular surface defects and degeneration such as wounds and ulcers through corneal infection. With a ...

Immunology and Infection

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 dimensional (2D) and three dimensional (3D) culture has generated a wealth of information not only about corneal biology but also about wound healing, myofibroblast biology, and scarring in general. The goal of the protocol is an assay system for quantifying myofibroblast development, which characterizes scarring. We demonstrate a corneal organ culture ex vivo model using pig eyes. In this anterior keratectomy wound, corneas still in the globe are wounded with a circular blade called a trephine. A plug of approximately 1/3 of the anterior cornea is removed including the epithelium, the basement membrane, and the anterior part of the stroma. After wounding, corneas are cut from the globe, mounted on a collagen/agar base, and cultured for two weeks in supplemented-serum free medium with stabilized vitamin C to augment cell proliferation and extracellular matrix secretion by resident fibroblasts. Activation of myofibroblasts in the anterior stroma is evident in the healed cornea. This model can be used to assay wound closure, the development of myofibroblasts and fibrotic markers, and for toxicology studies. In addition, the effects of small molecule inhibitors as well as lipid-mediated siRNA transfection for gene knockdown can be tested in this system.

A protocol for an ex vivo corneal organ culture model useful for wound healing studies is described. This model system can be used to assess the effects of agents to promote regenerative healing or drug toxicity in an organized 3D multicellular environment.

Corneoscleral Button Isolation: A Surgical Procedure to Obtain Corneoscleral Button from Porcine Eye

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