Successful micronucleus testing with the EPI/001 3D reconstructed epidermis model: preliminary findings

Area of Science:

• Toxicology
• Dermatology
• In vitro testing

Background:

• The cosmetics industry uses in vitro genotoxicity tests for chemical safety assessment.
• The cytokinesis-block micronucleus (CBMN) test is a standard method, but has limitations.
• Reconstituted human epidermis (RHE) models offer a skin-like environment for safety testing.

Purpose of the Study:

• To evaluate the suitability of two RHE models (EPI/001 and RHE/S/17) for the micronucleus test.
• To assess the impact of chemical treatments on RHE model integrity and genotoxicity assay performance.

Main Methods:

• Two RHE models, EPI/001 and RHE/S/17, were exposed to acetone, mitomycin C, and vinblastine.
• Micronucleus frequency, cell viability, and tissue structure were analyzed.
• The number of binucleated cells was quantified to assess test suitability.

Main Results:

• Acetone did not affect micronucleus frequency, viability, or structure in RHE models.
• EPI/001 showed a dose-dependent increase in micronuclei with mitomycin C and vinblastine, despite reduced viability.
• RHE/S/17 yielded too few binucleated cells for reliable micronucleus testing.

Conclusions:

• The EPI/001 model is potentially suitable for in vitro genotoxicity testing using the micronucleus assay.
• The proliferative rate of the 3D tissue model is a critical factor for successful micronucleus test application.
• Further optimization may be needed for RHE models to enhance their utility in cosmetics safety assessments.