STRATICELL - In Vitro Skin Models & Testing Dermo-Cosmetics

StratiCELL has an innovative device to show the pigmenting effect of a product on the macroscopic appearance of pigmented skin reconstructed in vitro, comparable to a clinical trial. High definition pictures are taken during or at the end of treatments and the device generates an automatic calculation of the individual typology angle (ITA), the pigmentation index (PI), and the colorimetric contrast (ΔC) of the skin. StratiCELL can also performed melanin content quantification (Solvable®), melanin staining (Fontana Masson) and immunolabelling of key biomarkers (TYRP1, MART1, etc.).Because the skin pigmentation process is more complicated than a simple synthesis of melanin, each of our pigmented skin models (3D) perfectly reproduces the complex and dynamic environments of cell interactions encountered “in vivo”. Our models include: Light to dark skin models with the photo-type of your choice Age Spots skin models Asian skin models and other ethnicities

Using functional and standardised 2D or 3D living skin models, the bioassays performed by StratiCELL are very powerful tools for assessing the efficacy and mechanisms of action of products aimed at reducing skin inflammation and increasing skin barrier resilience. Examples of assays performed at StratiCELL: Barrier resilience and biomarkers NFkB translocation/activation Morphological alterations (such as spongiosis) Cytokines and chemokines release (IL1a, IL-1ß, IL-6, IL-8, etc.)

StratiCELL offers evaluation of the effectiveness of active ingredients, formulations and / or finished products in protecting the skin against oxidative stress and molecular damages induced by different light rays. Examples of assays performed at StratiCELL: DNA damage (cyclobutane pyrimidine dimers) Stress response (p53, Heat Shock Proteins, NRF-2 pathway) Apoptosis (caspase-3) and Sunburn cells Inflammation (Langerhans cells phenotype) Protein oxidation Elastin degradation

The epidermal barrier undergoes continuous renewal through a process called homeostasis, during which epidermal stem cells provide new keratinocytes that will go through a complex maturation process to replace corneocytes that are constantly lost during the desquamation and tissue turnover. Active ingredients with an effect on the epidermal homeostasis can be screened by monitoring tissue cohesion markers and differentiation markers. The biological endpoints are assessed by immunofluorescence of proteins involved in: Tight junctions (claudins, occluding, ZO-1) Corneo-desmosomes (corneodesmosin, desmogleins) Cornified envelope (involucrin, loricrin, filaggrin) The effects of a test item on the skin barrier can also be evaluated by measuring: Resistance Trans-epidermal electric resistance (TEER) Diffusion Skin diffusion of chromogenic dyes StratiCELL has also designed a TaqMan low density qPCR array to study the expression levels of 96 target genes carefully selected.

StratiCELL offers an extensive range of assays dedicated to the study of the efficacy and mechanisms of action of cosmetic ingredients and / or formulations with anti-ageing properties, including functional tests and gene expression analyses. StratiCELL evaluates the efficacy of a compound by modulating the different levels of ECM composition. In addition, enzymatic activity can be measured to assess any inhibition or activation effect.

StratiCELL is renowned for its integrated gene expression profiling services, which range from single gene analysis by qRT-PCR to complete transcriptome profiling via DNA microarrays. Services also include the selection of the best in vitro models and assays, biological material collection, RNA extraction, quality assessment, quantification of gene expression levels and data analysis with a comprehensive biological interpretation focusing on cell and tissue functions directly related to the specifics of skin biology. Analysing gene expression changes using qRT-PCR TaqMan low density arrays offers the advantage of focusing on 96 to 384 target genes, carefully selected and identified as key factors in dermo-cosmetic benefits. StratiCELL has developed several standardized arrays to meet the objectives of different studies. However, the preparation of a customized array is always possible.

StratiCELL is renowned for its integrated gene expression profiling services, which range from single gene analysis by qRT-PCR to complete transcriptome profiling via DNA microarrays. Services also include the selection of the best in vitro models and assays, biological material collection, RNA extraction, quality assessment, quantification of gene expression levels and data analysis with a comprehensive biological interpretation focusing on cell and tissue functions directly related to the specifics of skin biology. Whole transcriptome analysis is based on the use of DNA microarrays to monitor the gene expression patterns of the entire genome and to provide deep insights into the mechanisms of action of a test product. This technology is essential for the identification and characterisation of a large number of genes/pathways that are either up-regulated or down-regulated by the test product under specific conditions (healthy or sensitive skin, exposed to UV or pollutants, etc.).

StratiCELL offers product objectivation studies on a wide range of skin models, including cell cultures in monolayer (keratinocytes, fibroblasts, melanocytes, adipocytes, sebocytes, sensory neurons, endothelial cells, etc.), human reconstituted epidermis and finally, human skin explants. All these 2D or 3D models can be derived from primary, hiPS-derived cells or from particular conditions (i.e. from psoriatic or AD patients), and can be stimulated or exposed to stress factors as required. Our skin models are manufactured in-house and are the results of more than 15 years of R&D innovations. Skin cells in monolayer cultures In vitro reconstituted human epidermis Ex vivo skin explants