When this test applies
Sensitization is required for essentially every device with patient contact under ISO 10993-1:2025. ISO 10993-10:2021 permits this in vitro route in place of an animal assay where the material and its clinical use fit the applicability domain — which is the whole point of it. Establishing that fit is the first question to settle, not the last.
When to run it
Early. It is faster and cheaper than the guinea pig maximisation study, so it belongs in the screening position: run it before you commit to an animal assay, and you may not need one. Note that OECD 442D covers the keratinocyte activation key event only; a full non-animal sensitization conclusion normally combines it with assays covering the other key events.
What a pass tells you
That luciferase induction stayed below the 1.5-fold threshold at concentrations below the cytotoxicity limit — a negative prediction for the keratinocyte activation key event. Per OECD 442D a positive call requires induction reaching 1.5-fold or more with a dose-response, below that cytotoxicity limit; the two conditions together are what make the call, not induction alone.
What it does not tell you
It addresses one key event in the sensitization pathway. It says nothing about peptide reactivity or dendritic cell activation, and on its own it is not a complete non-animal sensitization conclusion. Where the material falls outside the applicability domain of the assay — and some device materials do — the animal route remains the defensible option.
Method
Testing per ISO 10993-10:2021 following OECD 442D. Test material is prepared per OECD 442D and applied to an immortalised human keratinocyte reporter cell line, and luciferase induction is measured across a concentration series alongside a cytotoxicity determination. 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
The laboratory is ISO/IEC 17025 accredited and GLP certified, and the report is issued under Groenakker cover, in Groenakker’s report template or in your document template on request at no extra cost.
Usually ordered alongside
Cytotoxicity as the baseline screen, and the Magnusson-Kligman guinea pig maximisation study where the in vitro route does not cover the material or the submission calls for the animal assay. Chemical characterisation with an ISO 10993-17 assessment can also inform whether sensitization is a live concern at all.
