Anti Irritation Test

Anti-Irritation Test

An anti-irritation test rules out the possibility of any damage that your skin might undergo following the application of a cosmetic or skincare product. Some cosmetic or skincare products contain irritants that penetrate the epidermal layer of your skin and trigger a chain of immune reactions by the keratinocytes. This often leads to redness, itching, or pain in the area of contact.

We test all our formulations on human keratinocytes cell lines to check their anti-irritation effect.

What Are Human Keratinocytes & Why We Use It?

Keratinocytes represent the major cell type in the epidermal layer of the skin. They are highly specialized and play an integral role in maintaining skin physiology and repair by creating a tight barrier to prevent the entry of foreign substances, minimizing the loss of moisture, forming close bonds with the other cells in the epidermis, and acting as an immunomodulator. Human keratinocytes are an excellent tool for investigating the anti-irritation effect of our products as they provide an endless supply of look-alike cells, assuring immense reproducibility in an in vivo (testing on a living organism) environment.

How We Test The Anti-Irritation Effect Of Our Products?

Step 1

Inducing Irritation In The Cells

The first step involves inducing irritation in the keratinocyte cells by exposing them to Sodium dodecyl sulfate (SDS). SDS is an anionic detergent that acts as an irritant and rapidly disrupts the skin barrier,leading to inflammation. This event, in turn, initiates an immune reaction where damaged keratinocytes start releasing proteins known as cytokines. Cytokines are a group of proteins that facilitate interaction between cells. These special proteins recruit and activate more leukocytes (WBCs) through signaling in and between a variety of cells. Among many cytokines produced, the protein of interest IL-1 alpha is secreted in the largest amounts.

Step 2

Testing The Product

The next step involves introducing the test product & a cell media containing essential growth factors to another set of keratinocyte cells. With exposure to the test product,the cells may or may not undergo similar events that occur in the first step. We’ll confirm that by tracking the levels of IL-1 alpha post-treatment in both cases.

Step 3

Tracking The Level of IL-1 Alpha Cytokines

We compare the levels of IL-1 alpha post the treatment of keratinocytes with SDS as well as the test product using ELISA (Enzyme-linked Immuno-sorbent Assay) technology. Ideally, the level of IL-1 alpha in the case of our test product should be way lower than the amount of IL-1 alpha secreted in the case of SDS.

What's The Final Result?

For a product to be considered non-irritant, the ratio of IL-1 alpha cytokines levels in cell lines before and after treatment with the test product should be <50%. At Areoveda, the tested products reveal similar results!