[No public or meaningful name is available]

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vitro

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: SENS-IS assay

Principles of method if other than guideline:

SENS-IS is a new approach based on a reconstructed human skin model (Episkin) as the test system and on the analysis of the expression of a large panel of genes. The modulation of biomarkers is measured by quantitative reverse transcription-polymerase chain reaction (RT-PCR).
After exposure, gene expression of two groups of genes is measured:
 One group (REDOX group) includes a selection of genes that have an anti- oxidant responsive element (Keap1-NRF2 complex pathway).
 The second group (SENS-IS group) includes a selection of genes involved in inflammation, danger signals and cell migration to address the complex cascade of events leading to activation of DCs by a sensitizing chemical.

GLP compliance:

yes (incl. QA statement)

Type of study:

other: SENS-IS test

Justification for non-LLNA method:

This substance is an ingredient for cosmetical use only, therefore animal testing is prohibited.

Test material

Test material information

1

Reference substance name:

Silybum marianum extract

Molecular formula:

Not applicable

IUPAC Name:

Silybum marianum extract

Test material form:

liquid

Details on test material:

The test matérial contains 0.5% of tocophérol for stability

In vitro test system

Details on the study design:

After exposure, gene expression of two groups of genes is measured:
 One group (REDOX group) includes a selection of genes that have an anti- oxidant responsive element (Keap1-NRF2 complex pathway).
 The second group (SENS-IS group) includes a selection of genes involved in inflammation, danger signals and cell migration to address the complex cascade of events leading to activation of DCs by a sensitizing chemical.

Results and discussion

In vitro / in chemico

Results

Results 1

Key result

Run / experiment:

other: Irritation

Parameter:

other: number of overexpressed genes

Value:

1

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: No irritant (score < 15)

Results 2

Key result

Run / experiment:

other: Sensitization

Parameter:

other: number of overexpressed genes

Value:

1

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of skin sensitisation

Remarks:

Not sensitizer (score <6)

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Considering the number of overexpressed genes in the SENS-IS and ARE gene groups, the test item gave negative results (less than 7 genes induced) when it was diluted at 1, 10 and 50% (v/v) in olive oil. Moreover, negative results were also obtained when the test item was tested at 100%.
In conclusion, under the experimental conditions of the SENS-IS assay the test item can be classified as a non-sensitizer.

Executive summary:

The sensitization potential was tested according to SENS-IS assay.

Considering the number of overexpressed genes in the SENS-IS and ARE gene groups, the test item gave negative results (less than 7 genes induced) when it was diluted at 1, 10 and 50% (v/v) in olive oil. Moreover, negative results were also obtained when the test item was tested at 100%.

In conclusion, under the experimental conditions of the SENS-IS assay the test item can be classified as a non-sensitizer.