When this test applies
Sensitization is required for essentially every patient-contacting device under ISO 10993-1:2025. ISO 10993-10:2021 allows in vitro methods in place of the animal assays where the material falls within their applicability domain. KeratinoSens addresses keratinocyte activation (key event 2); a defensible in vitro conclusion normally combines it with a second method covering another key event, such as kDPRA for protein reactivity, which is why we recommend running the two together.
When to run it
Early — before committing to the guinea pig maximisation test. At 8 weeks it is faster than GPMT, materially cheaper, and avoids an animal study where the result is clear. Where a material is outside the applicability domain (for example certain metals, strongly coloured or highly insoluble extracts), confirm that with a scientist first; a result you cannot defend sends you to GPMT anyway.
What a pass tells you
That luciferase induction stayed below the 1.5-fold threshold at non-cytotoxic concentrations with no dose-response — a negative prediction for keratinocyte activation under OECD 442D. Read with a complementary assay, that supports a non-sensitizer conclusion under ISO 10993-10.
What it does not tell you
A single in vitro assay addresses one key event, not the whole sensitization pathway, and a negative result on its own is rarely sufficient for a submission. It also says nothing about irritation, cytotoxicity, systemic effects or genotoxicity.
Method
Testing per OECD 442D under ISO 10993-10:2021. The device extract is applied in a concentration series to an immortalised human keratinocyte reporter cell line carrying a luciferase gene under ARE control. After exposure, luciferase induction and cytotoxicity are measured; a positive prediction requires induction of 1.5-fold or more below the cytotoxicity limit with a concentration-response. Extraction ratio follows ISO 10993-12: 6 cm²/mL for material under 0.5 mm thick, 3 cm²/mL at 0.5 mm or thicker, or 0.1 to 0.2 g/mL where surface area is indeterminate.
Where it runs
Testing is performed to Groenakker protocols at an ISO/IEC 17025 accredited, GLP certified laboratory in Groenakker’s network, and the report is issued under Groenakker’s ISO 13485:2016 certified quality system, in Groenakker’s report template or in your document template on request at no extra cost.
Usually ordered alongside
A second in vitro method covering another key event (kDPRA, OECD 442C) to build the weight of evidence, with GPMT (GRK-4002-01) as the fallback where in vitro does not apply. Cytotoxicity and irritation complete the surface-contact baseline.
