SENS-IS® — In Vitro Skin Sensitization Testing
An in vitro assay combining reconstructed human epidermis with gene expression analysis to assess skin sensitization hazard and potency. Designed to assess a broad range of substances and products that may come into contact with the skin — from chemical substances, including poorly soluble and lipophilic substances, to complex mixtures, finished products and medical device extracts. Cosmetics · Chemicals · Pharmaceuticals · Agrochemicals · Medical Devices
What is SENS-IS?
SENS-IS® is an in vitro skin sensitization assay developed by ImmunoSearch to assess the sensitizing potential and potency of chemicals and products.
The assay combines IS-SKIN®, a reconstructed human epidermis model, with gene expression analysis. Test substances are applied directly to the surface of the 3D epidermis, allowing the biological response of human skin tissue to be measured after exposure.
SENS-IS analyzes the expression of 61 biomarkers covering sensitization, REDOX/ARE pathways and irritation. This genomic response provides more than a positive/negative result: it generates a biological signature that can help distinguish sensitization from irritation and characterize the response to the tested substance.
Because substances are applied topically to reconstructed epidermis, SENS-IS can accommodate a broad range of test materials, including poorly soluble and lipophilic substances, complex mixtures and finished products.
What SENS-IS tells you
SENS-IS goes beyond a simple positive or negative result. By analyzing the genomic response of the tissue, the assay provides three complementary levels of information.
Hazard identification
Determines whether a substance or product triggers a skin sensitization response.
Potency assessment
Testing across concentrations identifies the lowest concentration triggering a sensitization response. This concentration can be used as a Point of Departure (PoD) for risk assessment, analogous to the EC3 derived from the LLNA, while being obtained from a human reconstructed epidermis model.
Biological signature
The pattern of gene activation reveals how the tissue responds to the tested substance. Sensitization, REDOX/ARE and irritation biomarkers provide a biological fingerprint that can help distinguish different response profiles.
Together, these data provide a more comprehensive characterization of skin sensitization potential than a binary hazard result alone.
Validated performance
SENS-IS has been evaluated through extensive validation studies, including interlaboratory testing, demonstrating high reproducibility and predictive performance for skin sensitization hazard identification.
Up to 98%
Within-laboratory reproducibility
Up to 96%
Between-laboratory reproducibility
95%
Hazard prediction accuracy
Performance varies according to the validation dataset. See published studies for detailed results.
Performance has been demonstrated across independent laboratories and multiple datasets, supporting the robustness and transferability of the method.
Regulatory recognition
SENS-IS has progressed from scientific validation to international regulatory evaluation.
The method has undergone extensive validation and interlaboratory evaluation and is included in the OECD Test Guidelines Programme for skin sensitization hazard identification. SENS-IS is also registered in the EURL ECVAM Tracking System for Alternative methods towards Regulatory acceptance (TSAR).
ImmunoSearch operates SENS-IS under Good Laboratory Practice (GLP) for regulatory skin sensitization studies, providing a quality-assured framework for studies intended to support regulatory safety assessment.
The regulatory method is validated specifically with IS-SKIN™, ImmunoSearch’s proprietary reconstructed human epidermis model.
What can SENS-IS test?
SENS-IS evaluates a broad range of chemicals, complex mixtures and finished products, including substances that are difficult to assess using conventional in vitro assays.
Direct topical application onto reconstructed human epidermis enables testing of materials with diverse physicochemical properties, including poorly water-soluble and lipophilic substances.
Difficult-to-test chemicals
Poorly soluble, lipophilic, volatile substances and other challenging chemicals.
Complex mixtures & formulations
Essential oils, fragrances, surfactants and multi-component formulations.
Cosmetics & personal care products
Finished formulations, including creams, lotions and other skin-contact products.
Pharmaceuticals & topical drug products
Active pharmaceutical ingredients (APIs), topical creams, gels, ointments and transdermal patches or their extracts.
Medical devices
Polar and non-polar extracts of medical devices and skin-contact materials.
Industrial & agrochemical products
Chemical ingredients, intermediates and formulations used in industrial and agricultural applications.
Substance Testability
The SENS-IS assay excels in testing substances that are notoriously difficult to assess. When used to evaluate functional polysiloxanes and silanes, the SENS-IS assay demonstrated consistent and accurate predictions compared to in vivo methods like LLNA and GPMT, as well as other in vitro assays such as DPRA, KeratinoSens™, h-CLAT, and mMUSST (Petry, T. Regulatory Toxicology and Pharmacology 98 (2018) 209–214).
The SENS-IS assay not only matched the in vivo results but often surpassed other in vitro tests in predictive capability. It accurately forecasted the sensitization potential of polysiloxanes and silanes, including their potency, aligning closely with LLNA EC3 values. For substances like PS-4 and PS-8, where other assays like DPRA, KeratinoSens™, h-CLAT, or mMUSST showed inconsistent predictions, the SENS-IS assay stood out. These assays' limited metabolic capacity may lead to false negatives, especially for complex substances such as pro-haptens. In contrast, the SENS-IS assay demonstrated sufficient metabolic activation, converting potential pro-haptens into skin sensitizers with precision.
This robust predictive capability underscores the reliability of the SENS-IS assay, making it an essential tool for assessing the skin sensitization potential of various chemicals. Its consistent performance is invaluable, providing accurate and reliable results for even the most challenging substances.
Join Us in Revolutionizing Safety Testing
Join Us in Revolutionizing Safety Testing. At Immunosearch in Grasse, France, we believe in smarter, kinder science. We develop in vitro toxicology tests to keep products safe without relying on animals. Our team is dedicated to creating better solutions for cosmetics, perfumes, medical devices, and drugs. Ready to make a difference? Join us on this exciting journey.