Ocular Irritation Evaluation by Reconstructed Human Corneal Epithelium (RhCE) Model

Creative Biolabs utilizes the RhCE model to provide evaluation service of ocular irritation as a validated non-animal alternative to reliably classify mixtures and formulations to be evaluated based on their irritation properties.

RhCE Model Construction

The RhCE model provides a powerful platform to study corneal physiology and evaluate new ophthalmic drugs. This innovative model offers a more cost-effective way to delve into corneal structure, function, and responses, making it a pivotal asset in advancing ocular health and pharmaceutical development. The construction strategy of RhCE model is outlined below:

Acquisition of corneal epithelial cells
Corneal epithelial cells are derived from stable commercially available samples and cultured in appropriate media that maintained stable cellular function and morphological characteristics.
Preparation of the RhCE model
Cellular material obtained by serum-free in vitro culture on appropriate support material to construct multilayer RhCE models. It harbors specific markers such as keratins, CD44, and hemidesmosomes.
Recognizing the cell type and structure of the model
Performed immunohistochemical staining and microscopic observation to confirm the consistency of the major cell types and organization in the constructed multilayered corneal epithelial model with that of the original human corneal epithelium.
Validation
Validate the accuracy and reliability of the constructed RhCE model for known ocular irritants and new chemical substances.

The two ends and the middle part of RhCE are shown. Fig 1. Histological observation of RhCE.¹

RhCE Model Applied to Ocular Irritation Assessment

The following process of drug assessment emphasizes the pivotal role of RhCE model in advancing ocular irritation assessment.

RhCE model adaptation

Equilibrate the RhCE model overnight in the maintenance medium and transfer it to a test culture environment.

Preparation of test conditions

Negative control: PBS without calcium and magnesium ions.
Positive control: methyl acetate.
Object to be measured: PBS without calcium and magnesium ions and substance to be measured.

Collection of stimulus evaluation data

The object to be evaluated (e.g., formulation, drug) is applied to the constructed RhCE model and acted for a given time and concentration (allowing multiple time points and concentration gradients).

Assessment of cellular responses and toxicity

Assess the ocular irritation of the substance to be evaluated on the RhCE model using appropriate cell viability, cell morphology, immunohistochemistry, and genotoxicity. Compare the differences between the treated and control groups.

Data analysis and interpretation

To determine the ocular irritation characteristics of the substances to be evaluated using the mean tissue viability as a predictor. Statistical methods are used to verify the reliability of the results.

Mean tissue viability	Classification
>60%	Unclassified, non-irritating
≤60%	Potentially risky, category 1/2, irritating

Fig 2. Immunohistological (ZO-1) observation of RhCE after PM and UA treatment.¹

Strengths

Alternative to animal testing
Reduce reliance on animals such as rabbits and mice in traditional experiments and avoid unnecessary experimental manipulation and injury.
Human relevance
Human corneal epithelial cells are used as a source of model material to incubate the model for stronger human relevance and assessment accuracy.
Repeatability and standardization
The process of constructing and using the RhCE model is relatively standardized, and the reproducibility and comparability of experimental results are ensured by establishing a unified experimental process and standard operation.
Controllability
The use of the RhCE model allows for precise control of experimental conditions, such as concentration of stimulus, time, and mode of exposure. This allows more detailed and reliable data to be obtained.
Research efficiency and cost
RhCE models can be constructed relatively quickly, allowing multiple experiments to be performed and different stimulus substances to be tested simultaneously. It also reduces the time, cost, and resources involved in animal experiments.

Extensive 3D Biology Based Ocular Toxicity Evaluation Services

At Creative Biolabs, the RhCE model-based ocular irritation evaluation service provides a powerful tool for ocular research with great expertise. Please contact us to get a quote.

Reference

Ko, Ryota et al. "Effects of ambient particulate matter on a reconstructed human corneal epithelium model." Scientific reports. 11,1 (2021): 3417. Distributed under Open Access license CC BY 4.0, without modification.

Research Model

3D Biology Based Biomarker Discovery